endurance

Hack your Endurance with Rhodiola & Ginkgo

Rhodiola and ginkgo combination boosts endurance (no training required)

Supplementation with extracts of Ginkgo biloba and Rhodiola crenulata increases the stamina of young men. This is shown in a human study published in 2009 in the Chinese Journal of Integrative Medicine.

Study
The researchers, at the University of Hong Kong, divided 67 young men into 2 groups. For 7 weeks, they gave the men in one group placebo capsules and the men in the other group capsules containing extracts of Ginkgo biloba and Rhodiola crenulata in a ratio of 1: 9.

The men took 4 capsules each day, each containing 270 milligrams of extract mixture. They took 2 capsules with breakfast and 2 capsules with dinner.

Results
The supplement increased the men's stamina. The subjects in the experimental group managed to cycle longer, and that may have been due to the increase in their bodies' ability to absorb oxygen. [VO2max]

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Supplementation did not affect the test subjects' testosterone levels, but it did prevent cortisol levels from rising after exercise. That may mean that the men recovered faster.

Conclusion
"The present findings have provided evidence supporting the use of Rhodiola crenulata and Ginkgo biloba combined supplement for improving the endurance performance by increasing oxygen consumption and protecting against fatigue", summarize the researchers.

According to Russian animal study, extracts from both plants improve endurance, albeit in different ways. [Bull Exp Biol Med. 2003 Dec;136(6):585-7.]

How to Run Faster: Mental and Physical Techniques

 
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Guest post authored by Nate Martins from HVMN.com

What is speed? If we’re opening the dictionary, it’s a measurement of the rate at which someone or something is able to move; it also means to move quickly. Speed is both relative and concrete. It’s both an exact measure and a feeling with wholly different meanings depending on the context.

Speed is inexorably linked to time: seconds, minutes, mile splits, PRs. It can be easy to forget the idea of being fast, the heavy breathing, wind-through-your-hair, quad-burning sensation in which runners know they are hitting the ground but feel as if they’re floating.

Sam Robinson is a writer and marathoner–he has a PhD in history, has been featured in Outside Magazine, and is a fixture in the Bay Area running community. He recently discussed the idea of running philosophy on the HVMN Podcast.

“Fast is relative. It’s always good to keep that in mind.” — Sam Robinson

Fast is a feeling, one that maybe can’t be associated with time for all athletes.

Keeping Pace with the World’s Fastest Runners

During the 100m dash at the 2009 Berlin World Championships, sprinter Usain Bolt hit 27.8mph. Marathoner Dennis Kimetto ran the 2014 Berlin Marathon in 2:02:57 which was the fastest marathon of all time–until Eliud Kipchoge smashed that record on September 16, 2018 (also at Berlin) with a time of 2:01:39.

These runners exhibit different kinds of speed, each fast in their relative events. While Bolt hit a top speed of nearly 28mph, Kipchoge maintained over 13mph during his world-record setting marathon. The result was an average mile time of 4:38, faster than the max speed of the average treadmill (5 minutes per pace). These are the two extremes: sprints and marathons are almost entirely different sports and ways to exhibit speed.

Between these two efforts, middle distance running (800m, most commonly) provides a unique physiological middle ground.

One study cites the contribution from aerobic and anaerobic variables as allowing a runner to maintain speed during middle distance races. These runners are able to produce velocity without impairment from things like VO2 max (long-distance running), and lactate threshold (sprints).1

The world’s fastest 800m runner is David Rudisha, who holds the world and Olympic record set at London in 2012 with a time of 1:40. That effort broke his own record, set in 2010. Before that? The record was set in 1997 by Wilson Kipketer (who broke his own record several times). And before that? The record was set by Sebastian Coe in 1981. This is interesting when compared to marathon records (broken every few years) and 100m world records (broken even more frequently).

This is all to say that fast doesn’t exist in a vacuum. It depends on things like distance, event, output, and maybe most importantly for the casual runner, personal goal: a number, denoted in time, less than your previous run.

 
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We are not Bolt or Kipchoge. But we share a desire to run faster, whatever that may mean to you as a runner.

Mental Techniques

Running faster is something that must be achieved through physical ability–the body is what propels us forward. But now more than ever, the mental aspect of endurance exercise is being considered a powerful tool to push the body to extreme lengths.

“We’re so fixated on screens. Running is one of the times I can get away from that and be in my own head.” — Sam Robinson

The body and mind are linked; while we’ll explore physical aspects of technique and pacing, we’ll also address mental strategies to employ while on the road or the course.

Welcome the Pain

We previously discussed motivational techniques for runners, which points to embracing pain as a way runners can push themselves to log miles every day. The same is true for running faster. There’s an element of discomfort that must be welcomed in order to increase pace.

“Try not to see it as pain, just an intense sensation like spicy food or dark chocolate.” — Michael Brandt, HVMN Co-founder and COO

This is especially difficult for runners who are just starting because they’re not used to the feeling of pain. During workouts like speed training, the pain will come–it’s about being ready for it, anticipating it, and eventually, embracing it.

The pain will lessen with training. Crossing the lactate threshold is the point at which the body cannot recycle the lactic acid accumulated in the blood–it’s then that the body begins sending pain and nausea signals in an effort to make you slow down and thus recycle all that lactic acid. But you can train to increase that lactic threshold and decrease the pain.

With training also comes a knowledge of your body and an understanding of pain, remembering how it feels and at what point in the run it’ll hit.

Positive Thinking

The power of the mind can’t be understated–being aware of your thinking, and how those thoughts make you feel, can have a positive or negative impact on performance outputs. Sometimes telling yourself “you’re great” is the first step to actually making that happen.

One meta-analysis concluded the strategy of self-talk facilitates learning (so it can also help training) and enhance performance.2 Since self-talk has an impact on performance, it’s important to make that self-talk positive.

Cindra Kamphoff has a Ph.D in performance psychology, and she is a performance coach to professional athletes, executives and championships teams from all over the US. She understands the power of the mind and helps athletes harness it. When speaking about the mental aspect of sport, she had this to say: “The negativity is going to come, the disempowering thoughts are going to come because you’re pushing your body. You don’t have to believe them.”

While talking to yourself during a run, it also helps to be mindful. Many runners reach a flowstate of zen or a meditation-like experience. This happens during the run, but its power can be harnessed while off the trail. One study showed that several weeks of mindfulness training could help elite athletes adapt better to stressful situations.3

The ability to harness the connection between body and mind may lead to better results.

Chunking

No, this isn’t adding carbs to your pre-workout.

Breaking a casual run or race into chunks can help–especially for longer runs. This technique can help by making the total mileage feel less daunting. For a marathon distance, a popular way to break it down is into two 10-mile runs and a 10k.

Even on a smaller scale, chunking can be similar to gamifying the run. If you’re running in a city, you might push yourself to the end of the block. During a race, it’s undeniable that seeing the finish line can allow you to tap into a new running gear and push to the end.

Breaking down a run into smaller sections may help increase speed incrementally, which will likely lead to a better overall time.

 
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Training Smart

Training is like juggling. Breathing, form, power–all these things are on your mind with each stride. When one is dropped, the others tend to follow. But it’s during this training process that the best habits are built. And remember, it’s a process.

“Running is about playing the long game. Think of it like a house. A good race or bad race is a single brick in the edifice of your long-term fitness.” — Sam Robinson

Things like intervals and tempo runs can help. It’s also important to track your progress: keep a training log to see how you’ve been able to increase speed after all that hard training.

Intervals

Intervals are great speed workouts for both the aerobic and anaerobic system. They consist of short, high-intensity bursts followed by slow recovery phases which are repeated one after the other. One of the earliest forms of interval training was the Fartlek method (Swedish for “speed play”), and today, many athletes use high-intensity interval training (HIIT). Sometimes, running fast means actually running fast.

Generally, these workouts are ten seconds to several minutes long, run nearly at maximum effort, followed by a rest period of up to four times the length of the effort itself. The shorter the interval, the more of them you’ll likely do.

But the length of intervals (time and distance), power of those intervals, and the rest period, should be optimized for the specific runner. Elite runners can do four intervals of ten minute runs at their 5k pace. Most runners won’t be able to maintain that. An average interval workout is an 8x4: eight repeats of a 400m run done in 90 seconds with a two-minute recovery.

One study in soccer players found that HIIT improved maximal aerobic speed.4 And recreational runners can improve their running economy by replacing aspects of their conventional training with long-interval running.5

Hills

Hill training usually targets power in the legs, meaning higher output. One study found that six weeks of hill workouts increased top speed for runners, while also allowing them to sustain that speed 32% longer.6

Hill repeats are similar to interval training in that they’re usually conducted in short bursts. First, warm up. Then find a hill that’s about 100m long and run hard to the top, with the jog downhill serving as the recovery period. Start with two or four repeats, and work your way up to six or eight.

 
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Tempo Runs

Tempo runs are also known as lactate threshold runs–this is the point at which your body is unable to recycle accumulated lactate in the blood. This is a pace that’s anywhere between ten and 30 seconds slower than a 5k or 10k pace.

The goal of tempo runs is to increase your anaerobic threshold, thus allowing your body to sustain an effort that was previously unsustainable. This training technique tends to benefit longer-distance runners more than sprinters.

Tempo runs should be part of a weekly running routine, and can vary depending on experience level and training needs. One way to incorporate this into training is to start by running 15 - 20 minutes at 75% of maximum heart rate, then build up to 30 - 45 minutes by adding about five minutes to these runs weekly.

Strength Training

While many runners are laser-focused on logging miles, time in the gym can lead to time off your mile splits.7

Two areas of strength training are often employed by runners: leg and core workouts. Weight training can both improve strength and lead to greater running economy (as it did for female runners in this study).8

Exercises like lunges and squats can strengthen those leg muscles used more frequently on runs. And for core workouts, even simple additions like planks and leg raises and weighted sit-ups can positively impact form and posture. Don’t discount yoga and stretching–on days where you’re looking for some active recovery, yoga is perfect for both developing strength in core muscle groups and stretching tight muscles.

Fix Your Form

Essential to running efficiently, improving running form and technique can lead to faster speed. The way you run affects the way force is applied to your muscles and joints. Correcting form can be help injury prevention, as improper execution can cause injury if you’re a beginner;9 if you aren’t running, you aren’t getting faster.

“People assume that running is running is running, but it's not true. Especially when we sit at our desks all day, or aren't used to it.” — Michael Brandt, HVMN Co-founder and COO

Good overall form can feel like a unicorn; it’s best broken down into a few manageable techniques to consider on each run.

Stride Turnover

Changing stride turnover–how my steps taken during one minute of running–may have an impact on speed.10

The goal is to have a higher stride turnover, meaning to take shorter, quicker steps; these reduce the impact on your joints because you’ll hit the ground with less force. Longer strides have the opposite effect, and can create more impact because you’re in the air for longer. Sprinters will typically need to lift their knees higher to achieve maximum leg power, but distance runners won’t need as much lift.

Figuring out your stride turnover is easy. Just run for one minute at your 5k pace and count the number of times your right foot hits the ground. To improve stride turnover, jog for one minute to recover, trying to increase your stride count by one. Repeat this several times with the goal of increasing strides each time.

At the proper stride length, your feet should land directly under your body. And when your foot strikes the ground, your knee should be slightly flexed, bending naturally to the impact. Keep in mind that the middle of your foot should be making contact with the ground–not your heel.

Heel Striking

It’s a very common problem for runners.11 Landing on your heel can mean too long of a stride, which wastes energy and may cause running injuries (hello, shin splints).12 Avoid landing on toes too–this can also increase fatigue and wear out your calves.

You want to be a mid-foot striker. Hitting the ground mid-foot allows you to roll through to the front of your toes. Changing your footstrike takes practice, but the results can show up both in speed and in reduced joint pain. One study of runners from habitually barefoot populations showed an increase in speed when mid-foot or front-foot striking.13

Overstriding is usually the culprit–try increasing your number of strides. Your next run, focus on striking on the balls of your feet. Interestingly, that’s where most people strike when running barefoot; try running on grass (or another soft surface) without any shoes on, translating that muscle memory to other runs. Also, running drills can help. Skipping, high knees, side shuffling, butt kicks–with all these, it’s almost impossible to land on the heel.

One last thing. It may seem obvious, but keep those toes pointed in the direction you want to travel. As fatigue sets in, form gets wonky–you may find your toes are turning in or out, which can lead to joint pain.

Relax

It goes from top to bottom and will have an impact on running posture.

Relax your shoulders. Relax your arms. Relax your hands.

 
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Posture

“Running tall” is a repeated mantra meant to encourage good running posture.

It starts with the head: look ahead naturally while keeping the chin parallel to the ground, and avoid looking down at the feet. This should improve posture in your neck, shoulders and back–which, remember, should be relaxed.

Avoid hiking up your shoulders, which can happen naturally with stress. Upon feeling your shoulders close your ears, try giving them a good shake to relax and keep them level.

Efficient running means less overall movement. Arms, at a 90-degree angle, should swing back and forth around the waist, powering the lower body. Think of yourself as two halves: left and right, and keep each arm on that side of the body. Tension in the upper body is controlled by the hands, so relaxed hands are also important. You may notice tension developing throughout the run as it gets more difficult–imagine you’re carrying an egg in each hand and watch that tension disappear.

The torso and back should be naturally straight, as this promotes optimal lung capacity and stride length. Slouching during a run? Try a deep, realigning breath and hold position.

Breathing

We’ve discussed VO2 max, and its impact on the body’s ability to use oxygen efficiently. Since oxygen is feeding those muscles, it’s important to understand how to take in the most air possible.

Inhale and exhale primarily through your mouth–it’s the most effective way to take in oxygen. Your nose can join the party too, but it can be difficult for some to breathe through both simultaneously. Practice makes perfect here; you can try it throughout the day to help get the body adapted to the technique.

And focus on belly breathing, with the force of the inhale extending to the diaphragm with the stomach expanding. These should be deep, slow, rhythmic breaths. Overall, you should see a decrease in cramps and an increased ability to pace yourself.

Sleep & Recovery

The importance of rest cannot be understated–but it’s often forgotten or unaccounted for in a training plan.

“Our culture has a ‘no pain, no gain’ mindset. But that’s not how the body works exactly. You need to recover properly.” — Sam Robinson

Sleep and recovery days are important to give tired muscles a chance to rebuild tissues that have been broken down during exercise.14 That breakdown is meant to cause muscles to adapt and become stronger, thus potentially leading to increased speed. Sleep is also part of this process. It’s important to encourage good sleep: set a sleep schedule and get some screenless time before bed, because screens can negatively impact rest.15 One study found that lack of sleep can lead to muscle degradation.16

Recovery runs are a must. These should be done at a slower, less-strenuous pace that allows the body to recycle lactate as its produced. This pace per mile should be about one minute or 1:30 more than your average pace.

Consuming Your Way to Speed

What you eat, and the supplements you take, can have an impact on how fast you run. A body operating on high-octane fuel will undoubtedly perform better than one with a less-optimized fuel source.

Diet

Diet can have a roundabout effect on speed through a few different avenues.

It directly impacts body composition, which affects speed. It can also determine the body’s fuel source, meaning that a diet low in carbohydrates can lead to fat-adaptation, allowing the body to tap into fat stores. If you aren’t a fat burner, carbs are essential to keep running pace, as glycogen depletion leads to bonking. And after a run, diet can help with recovery, enabling the body to train again faster.

VO2 max is a measure of one’s running fitness; it’s the maximum amount of oxygen that can be delivered to working muscle per unit of body mass. Those with higher VO2 maxes are better runners. And because body weight impacts VO2 max, the lighter the runner means a higher VO2 max which can mean a lighter runner is a better runner.

Many distance runners are employing the ketogenic diet for weight loss. The low-carb, high-fat diet can force a metabolic adaptation allowing the runner to burn fat as fuel (as opposed to carbs). And the restricting of carbohydrates often leads to better body composition.

Counting calories may help you lose weight. While the macronutrient composition of food can be more important than the amount of calories, counting calories while on keto might lead to greater results.

 
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Supplements

We’ve covered supplements for runners extensively, providing you with a toolkit from training to race day to recovery. You’ll want to focus on those for race day, as they’re the supplements that can have a direct correlation to speed.

Many runners drink coffee and consume carbohydrates before a race, giving the body fuel sources to immediately tap into. Buffers are also useful, and may delay the onset of muscle pain associated with the building up lactic acid in the blood (but really it’s the proton associated with lactate)–check out sodium bicarbonate, Beta-alanine and HVMN Ketone.

HVMN Ketone

Ketones are a fundamentally different fuel source from carbohydrates and fats that cells normally use for energy.

Taken before or during exercise, D-BHB (the ketone body in HVMN Ketone) is 28% more efficient than carbohydrates alone, helping your body do more work with the same amount of oxygen.17 In one study, cyclists went ~2% further in a 30-minute time trial.18

When taken with carbs, the glycogen-sparing effect of HVMN Ketone helps many runners–the body will preferentially use the ketones as fuel first, saving glycogen for later in the race, when the need it most.

"By consuming exogenous ketones, athletes give themselves an additional source of fuel that they can burn first, thus preserving glycogen." — Allison Goldstein, Runner’s World

HVMN Athlete and professional cyclists, Vittoria Bussi, recently broke the world record for the women’s Hour: riders see how far they can cycle in a velodrome in one hour. Vittoria used HVMN Ketone before her attempt, citing its effectiveness later in the race.

 
 

Read more about Vittoria’s story here.

Running Fast: a Personal Pursuit

With countless ways to measure and track and compare and share statuses, it’s important to remember that on a run, it’s just you and the road. You should want to improve. You should want to get faster. You should expect to work to get there.

Running isn’t about taking shortcuts, if you want to get faster, you have to train. Aspire to some of the world’s best runners, and use that as motivation each time you lace up your shoes to run.

Want to get even faster?

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Scientific Citations

1.Brandon LJ. Physiological factors associated with middle distance running performance. Sports Med. 1995 Apr;19(4):268-77.
2.Hatzigeorgiadis A, Zourbanos N, Galanis E, Theodorakis Y. Self-Talk and Sports Performance: A Meta-Analysis. Perspectives on Psychological Science. 2011 July; 6(4): 348-356. https://doi.org/10.1177/1745691611413136
3.Haase L, May AC, Falahpour M, et al. A pilot study investigating changes in neural processing after mindfulness training in elite athletes. Front. Behav. Neurosci., 27 August 2015 | https://doi.org/10.3389/fnbeh.2015.00229
4.Dupont G, Akakpo, K, Berthoin, S. The Effect of In-Season, High-Intensity Interval Training in Soccer Players. Journal of Strength and Conditioning Research: 2004; 18(3): 584–589.
5.Franch J, Madsen K, Djurhuus MS, Pedersen PK. Improved running economy following intensified training correlates with reduced ventilatory demands. Medicine and Science in Sports and Exercise [01 Aug 1998, 30(8):1250-1256].
6.Ferley D, Hopper DT, Vukovich M. Incline Treadmill Interval Training: Short vs. Long Bouts and the Effects on Distance Running Performance. International Journal of Sports Medicine 2016 Aug; 37(12). DOI: 10.1055/s-0042-109539
7.Storen O, Helgerud J, Stoa EM, Hoff J. Maximal Strength Training Improves Running Economy in Distance Runners. Med. Sci. Sports Exerc., Vol. 40, No. 6, pp. 1089–1094, 2008.
8.Johnston RE, Quinn TJ, Kertzer R, Vroman NB. Strength training in female distance runners: Impact on running economy. J. Strength and Cond. Res. 11(4):224-229. 1997
9.Kluitenberg B, van Middelkoop M, Diercks R, van der Worp H. What are the Differences in Injury Proportions Between Different Populations of Runners? A Systematic Review and Meta-Analysis. Sports Med. 2015; 45(8): 1143–1161. doi: 10.1007/s40279-015-0331-x
10.Hogberg, P. Arbeitsphysiologie (1952) 14: 437. https://doi.org/10.1007/BF00934423
11.Larson P, Higgins E, Kaminski J, et al. Foot strike patterns of recreational and sub-elite runners in a long-distance road race, Journal of Sports Sciences. 2011;29:15, 1665-1673, DOI: 10.1080/02640414.2011.610347
12.Daoud, AI, Geissler GJ, Wang F, Saretsky J, Daoud YA, Lieberman DE. Foot Strike and Injury Rates in Endurance Runners: A Retrospective Study. Med. Sci. Sports Exerc., Vol. 44, No. 7, pp. 1325–1334, 2012
13.Hatala KG, Dingwall HL, Wunderlich RE, Richmond BG (2013) Variation in Foot Strike Patterns during Running among Habitually Barefoot Populations. PLoS ONE 8(1): e52548. https://doi.org/10.1371/journal.pone.0052548
14.Parra J, Cadefau J A, Rodas G, Amigo N, Cusso R. The distribution of rest periods affects performance and adaptations of energy metabolism induced by high‐intensity training in human muscle. Acta Physiologica Scandinavica, 169: 157-165.
15.Exelmans L, Van den Bulck J .Bedtime mobile phone use and sleep in adults. Soc Sci Med. 2016 Jan;148:93-101.
16.Dattilo M, Antunes H K M, Medeiros A, Mônico Neto M, Souza H S, Tufika S, de Mello M T. Sleep and muscle recovery: Endocrinological and molecular basis for a new and promising hypothesis. Medical Hypotheses Volume 77, Issue 2, August 2011, Pages 220-222.
17.Sato, K., Kashiw.aya, Y., Keon, C.A., Tsuchiya, N., King, M.T., Radda, G.K., Chance, B., Clarke, K., and Veech, RL. (1995). Insulin, ketone bodies, and mitochondrial energy transduction. FASEB J. 9, 651-658.
18.Cox, P.J., Kirk, T., Ashmore, T., Willerton, K., Evans, R., Smith, A., Murray, Andrew J., Stubbs, B., West, J., McLure, Stewart W., et al. (2016). Nutritional Ketosis Alters Fuel Preference and Thereby Endurance Performance in Athletes. Cell Metabolism 24, 1-13.

Endurance vs. Conditioning

The statement is simple – Endurance is the most overrated of all sports specific qualities. Why Because endurance is neither necessary nor the limiting factor in most sports. Conditioning is. Where is the difference?

Definition of Endurance and Conditioning as follows:

Endurance is the ability to maintain a certain effort with minimal fatigue – A classic example is a marathon. At a marathon it´s crucial to run 2+ h in one go with minimal fatigue.

Conditioning is the ability to repeat a certain effort with minimal fatigue – Classic examples are team sports like Soccer, American Football, Basketball and Ice hockey. In those sports it is crucial to keep fatigue between the first and the last sprint (and all the others in between) as minimal as possible.

Most Olympic, Team- and Combat Sports are cyclical, that means certain efforts must be repeated. A 100m sprinter has to repeat his performance in heats, semi-finals and finals. A thrower has 6 attempts per competition and an olympic weightlifter has 3 per discipline.  If the performance decreases too much from attempt to attempt then his conditioning is the limiting factor.

A more extensive example is soccer. Depending on the position of a player he runs about 8-12km per game. From which he runs 400-1200m above 85% of his top speed. The remaining 8-10km are walking, trotting and hardly relevant for the game.

These 400-1200m are crucial. The average sprinting distance is about 17m. Sprints over 30m, thats the distance between mid- and penalty line, are very rare.

The critical distance is 0-5 m. That´s the famous “one step faster”. Based on player statistics of the English Premier League, players with the highest salary, regardless of their position have one thing in common, they are the fastest over 0-5m.

At an average sprinting distance of about 17m and a game-relevant total distance of 400-1200m those are about 24 to 70 sprints per game. Assuming a uniform load density, it is a load of 2-3 seconds followed by a 1:20-4:00 minute break. I sprints are repeated with minimal rest its more than 3 in a row before the ball is out of sight.

So what is critical for a game in this case in terms of physical qualities?

Endurance or Conditioning?

Critical are those 24 to 70 sprints in under 90 minutes game time and their repetition with minimal fatigue, not endurance. Endurance isn´t relevant in soccer because of the short bursts of sprints they do.

To run 10-60 minutes at once has very poor correlation with the ability to repeat 24 to 70 sprints in 90 minutes with minimal fatigue.

2 FORMS OF ENDURANCE

Endurance at high intensity – that is the ability to maintain a stress of high intensity upright with minimal fatigue. A good example is a 100m sprinter. A sprinter reaches his top speed after 60-70m. From 60-70m the critical factor becomes maintaining the top speed as long as possible without getting tired. In this case we speak of speed endurance. Usain Bolt is a great example for this. His greatest advantage over his opponents, and the reason why he is even more dominant over 200m than over 100m, is his exceptional speed endurance, the ability to maintain his top speed with minimal fatigue and leave all his opponents behind after 60-70m.

Endurance at low intensity – that is the ability to maintain a stress of low intensity upright with minimal fatigue. A good example is the marathon. In a marathon it´s crucial to maintain a performance for 2+ h with minimal fatigue. In one go and without interruptions.

Intensity – definition: Intensity is the load of a performance in relation to the maximal performance. A performance at high intensity for example is a sprint over 50 meters at maximum speed or BB Back Squats for 3 reps with 90 % of 1RM. In contrast to this, a performance of low intensity is a run over 10000m at maximum speed or squats for 25 reps with 50 % of 1RM. That means intensity is not defined on the subjective level of effort but correlates performance with maximum power/effort.

Both forms of endurance, especially the last one, are not relevant in most Olympic-, Team- and Combat Sports because the duration of the load in those sports is far lower.

In most Olympic-, Team- and Combat sports conditioning is critical. The ability to repeat a performance with minimal fatigue.

2 FORMS OF CONDITIONING

Conditioning at high volume – the ability to repeat a certain performance very often with minimal fatigue.  The best example is soccer, where depending on the position of the player the average sprinting distance has to be repeated up to 70 times per game with minimal fatigue.

Conditioning at low volume – the ability to repeat a certain performance a few times with minimal fatigue. Best example is Olympic Weightlifting. There you only have to repeat an attempt 3 times per discipline and competition – so 3 Reps of the Snatch and 3 Reps of the Clean & Jerk, thats it.

The lower the volume, the more critical becomes the performance during the attempt itself. It is not that crucial to repeat that performance often.

The higher the volume, the more critical is the ability to repeat it. Therefore in weightlifting the ability to repeat a performance is less important than the absolute performance, namely to move maximal weight. In comparison with weightlifting soccer players need lower maximal- and explosive strength level than weightlifters – but higher levels of conditioning. As the ability to repeat maximal Sprinting Speed for the 90 minute game is critical.

TRAINING ENDURANCE VS. CONDITIONING

The training for Endurance and Conditioning is obviously very different.

The Training of Endurance basically includes a higher volume of total work, a lower -if any – number and duration of breaks and lower average intensity of effort. While the training of conditioning basically comprises a lower total volume of work and an increased number and duration of breaks at higher average intensity of effort.

51 rounds divided into 3 blocks á (9 rounds, 3 minutes pause, 5 rounds, 3 minutes pause, 3 rounds) with 10 minute pauses between the blocks. The rounds have to be executed with minimal 85% of world record time.

That´s a solution for a 1500m short track speed skater whose limiting factor is endurance over 1500m. That means he fatigues too much in the last 3-5 rounds of the 1500m race which is 14,5 rounds.

This is a program written by the legendary short track speed skating Coach Yves Nadeau, whose athletes won 204 medals at World Championchips and the Olympic Games since 1983.

Sample training program for Conditioning in Soccer

This is a modified strongman medley used to condition a soccer player

A1 Forward Sleddrag, 20m, 5s rest
A2 Prowler Push, High Handle, elbows extended, 20m, 5s rest
A3 Sprint, 20m, 120s rest
Repeat 4-10 times depending on the current Conditioning Level of the Athletes

This is a solution for a player or a team whose physically limiting factor is fatigue in the latter part of the game.

The ability to repeat multiple blocks of three 20m efforts with minimal rest has clearly a higher correlation to soccer-specific performance than 10-60min straight jogging. To train the sprinting power, speed and conditioning at the same time a combination of strength- and condititoning training in the weightroom can also be utilized. To see how it looks in detail, here is an example of a squat training program for conditioning in Ju Jitsu.

Sample training program for Conditioning in Ju Jitsu

 12 sets of 4 reps of BB Back Squats with a 30X0 tempo and 60s rest.

From workout to workout increase the average- and maximal weight used.

That´s a solution for a fighter whose physical limiting factor is fatiguing from effort to effort. The higher intensity and resistance on the squats allow for training conditioning and power of a single action at the same time.

This is the program used for preparation of YPSI Athlete Romy Korn for the Ju Jitsu World Championship 2014 in Paris where she became World Champion in the 70+ kg weightclass at a bodyweight of 71,2kg with all her opponents outweighing her by 15+kg.

Conclusion: For a coach it is crucial to identify whether endurance and/or conditioning are necessary for a certain sports and disciplines. And to assess which the limiting factor of the individual athlete is. So the training program can be specifically tailored to the needs of the individual sport and the limiting factor of the individual athlete. To maximise the efficiency of training and therefore increase pPerformance on the field, court, ice or mat.

Resistance Training’s Effect on Endurance Performance

Research shows that the appropriate integration of resistance training into the endurance athlete’s training can result in significantly better performance when compared to classic endurance training plans that focus only on aerobic endurance.

Research shows that the appropriate integration of resistance training into the endurance athlete’s training can result in significantly better performance when compared to classic endurance training plans that focus only on aerobic endurance.

The following is an exclusive excerpt from the book Developing Speedpart of the NSCA’s Science of Strength and Conditioning Series with Human Kinetics.

Endurance athletes who are stronger can generally perform at a much higher level.

This suggests that training modalities that stimulate increases in muscular strength without compromising endurance capacity may be beneficial for the endurance athlete. Support for this contention can be found in the scientific literature; research shows that the appropriate integration of resistance training into the endurance athlete’s training plan can result in significantly better performance when compared to classic endurance training plans that focus only on aerobic endurance training.

When looking closely at endurance performance, several key factors—including the athlete’s maximal aerobic power (V˙ O2max), lactate threshold, and movement efficiency—contribute to performance (see figure 7.1). The training modality selected influences these factors by inducing changes to the athlete’s aerobic power and capacity, anaerobic capabilities, and neuromuscular function.

Aerobic training exerts a strong influence on both aerobic power and capacity, but it does not exert a great impact on the athlete’s anaerobic or neuromuscular abilities.

Conversely, resistance training exerts a strong influence on the athlete’s neuromuscular function and a moderate influence on anaerobic power and capacity, while offering only a minimal influence on aerobic power and capacity. By influencing the athlete’s anaerobic abilities as well as neuromuscular function, resistance training can elevate the athlete’s lactate threshold, movement efficiency, and ability to engage in high-intensity activities.

The ability of resistance training to improve endurance performance is likely related to several key factors, including the specific physiological and mechanical adaptations that are stimulated by the resistance training regimen. The integration of resistance training into the overall training plan appears to be central to creating these specific performance-enhancing adaptations.

Traditionally, endurance athletes and coaches have believed that resistance training either does not affect or negatively affects endurance performance. However, this view may be partially explained by a design flaw in many of the training programs that include both resistance and endurance training. The flaw is that resistance training is simply added to the endurance training plan. Athletes who undertake this approach often experience excessively high levels of fatigue that can negatively affect overall performance.

If athletes reduce their endurance training load to account for the addition of resistance training, then resistance training has a positive effect on the athletes’ endurance performance. The athlete who performs both resistance and endurance training in an integrated and appropriately planned fashion will perform at a higher level than the athlete who performs only classic endurance training.

Chocolate Milk For Post-Workout: A Look at the Research

Over recent years, there has been a massive initiative to promote chocolate milk as “the best” drink for post-training recovery. Milk advertisers use very high level athletes as spokespersons to sell a product to people who are indeed active, but often very far from the training level of an Olympic athlete.

Nautilus Plus is participating to this initiative: “Whether you are a professional athlete or a weekend sports enthusiast, recover from your next training faster with the Ultimate Chocolate Milk®.”(1) Do we really need to fill ourselves with all this added sugar after our training?

One litre of chocolate milk contains up to 100 to 110 g of sugar!!! The quantity of sugar that the body can absorb is limited. In fact, the sugar will be stored in the liver and muscles in the form of glycogen, which only represents 5 % of the body’s total energy reserves (2). If your objective is, as for the majority of people, to lose fat, you need to remember this: to allow yourself to consume a supplement rich in carbohydrates after your training, you will have to have emptied or seriously depleted your glycogen stores in order for the extra sugar absorbed to be used to renew your glycogen stores. And if you absorb more sugar than you need to renew your reserves, it will be transformed into fat (3).

Scientific studies

Many scientific studies have been done on sports nutrition supplements and some included chocolate milk. The purpose of these studies was to determine which mixture of molecules, and in what proportion, best promotes post-training recovery as well as athletic performance. Almost all these studies followed this particular protocol:

  1.  Study participants were subjected to intense exercise at 70 to 85% of their VO2 max during 1 to 3 hours. The purpose of this step was to considerably reduce the muscle and hepatic glycogen stores since 70 to 80% of the energy spent at 85% VO2 max is derived from glycogen. Under 65% of VO2 max, mostly fatty acids are used (4, 5).
  2. A recovery period between 4 and 8 hours followed to allow the participants to replenish their glycogen stores with the various sports nutrition supplements covered in the study.
  3. Participants were then subjected to a second high intensity exercise (VO2 max between 70 and 85%) until exhaustion (loss of 85 to 95% of their hepatic glycogen and 65 to 85 % of their muscle glycogen) (6). The difference in time or distance between the performances will determine which sports nutrition supplements helped the athlete the most to recuperate between the two sessions.
    .

The role of these sports nutrition supplements is therefore to replenish as quickly and efficiently as possible the glycogen stores which were SIGNIFICANTLY depleted during the first training, in order to allow a second intense performance within 4 to 8 hours.

This situation is certainly frequent among Olympic athletes or athletes from the Tour de France who train several times per day or several days in a row at extreme intensities, but what about other people? Is chocolate milk a good supplement for “weekend athletes” or people who train leisurely, three of four times per week?

After your leisure strength training?

For a person who does resistance strength training, the glycogen stores will fall by 25 to 40 % after an intense strength training (7 to 12), which is relatively little. The glycogen stores lost during the training will be rebuilt through normal nutrition, WITHOUT ANY SUPPLEMENTS, within 24 hours of the training. However, some people consider it very important to MAXIMIZE the production of lean muscle mass. So the rapid intake of PROTEIN supplements after the training (within 1 hour if possible, up to 3 hours later) is important since it promotes maximum muscle synthesis(13 to 33). Recently, a research team questioned this principle claiming that it would be the total quantity of proteins ingested each day that would prevail over the moment at which they are ingested (34, 35). The same team also mentioned that if a “window” for taking a protein supplement and maximizing the production of lean muscle mass does exist, it would rather span over a 4 to 6 hour period following the strength training.

According to various recent studies, 20 to 25g of proteins would be the recommended amount to take after a resistance training (25, 33, 36). Witard et al., 2014 consider that 20 g of whey protein containing approximately 2 g of leucine optimally stimulates muscle synthesis (33). A litre of chocolate milk contains approximately 30g of proteins, including 80% of micellar casein and 20% of whey (37). Studies on post-training muscle synthesis clearly show the very poor efficiency of micellar casein for this purpose (26, 28, 38, 39, 40) because it precipitates in the stomach and the absorption of amino acids responsible for muscle synthesis is therefore very slow (26, 41, 42, 43). One argument that is often used by chocolate milk advocates is that milk (skim) is more efficient than soy protein or casein to promote muscle synthesis (23, 24). That’s true! It is actually the 20% of whey proteins contained in the milk that makes it efficient for muscle regeneration (26, 28, 40). What they don’t say is that purified whey protein (concentrate or isolate) is the best all around for lean muscle mass gain (26, 28, 40, 44, 45, 37) and, consequently, is better than milk. Whey protein is very rich in BCAA and is quickly absorbed by the intestine, as opposed to casein which is absorbed slowly. Therefore, why take a milk supplement if a whey protein shake is more efficient? Not only does chocolate milk contain large quantities of casein, but it can also contain saturated fat (if it’s full fat) as well as a large quantity of added simple sugars, on top of the lactose. So, is it useful to add all this sugar to the proteins (which are already not optimal) to maximize muscle synthesis after my resistance training?

Some studies show that carbohydrates (CHO) could inhibit muscle breakdown caused by training (10, 46, 47, 48, 49). A few groups claim that a carbohydrate/protein (CHO:PRO) supplement would facilitate a better muscle synthesis since it would inhibit muscle breakdown (15, 32, 46, 48, 50, 51). Nevertheless, some of these studies did not include a control group for the proteins (PRO) only. So it is difficult to evaluate whether adding CHO to PRO provides an advantage or not over PRO taken separately. As for the few studies that included a control group for the PRO, the quantity used was sub-optimal and was given in the form of amino acids (46, 48, 50). However, when a control group taking PRO optimally is included in the study, adding CHO to PRO did not show any advantage in terms of lean muscle mass gain (49, 52 to 57). CHO: PRO ratios used in the studies on resistance training varied between 1:1 and 3:1 whereas chocolate milk offers a ratio between 3:1 and 4:1. That is a lot of unnecessary sugar!

In turn, adding CHO to protein supplements can be necessary when several INTENSIVE resistance trainings are planned during the same day. In such a case, the athlete must quickly renew its glycogen stores (58, 59). To this end, 1g/kg of weight of CHO should be added to the proteins and consumed immediately after the training; moreover, a meal should follow 2 hours after the training (59, 60)So you must weigh at least 220 lbs and must train intensely more than once a day to allow yourself a litre of chocolate milk. Even then, you won’t achieve optimal results because of the casein, which constitutes 80% of the total proteins, and because of the 2:1:0.46 (glucose:fructose:galactose) ratio of the various sugars present in the chocolate milk (61).

The fructose contained in chocolate milk comes from high fructose corn syrup (which has a very bad reputation) and from sucrose (1 glucose +1 fructose). In 2004, Bray GA et al. suggested that the obesity epidemic in the United-States was related to the HFCS found everywhere and in large quantities in our nutrition (62). However, the new report published by The International Journal of Obesity, 2015 (63) suggests that this epidemic cannot be linked to HFCS due to the lack of evidence demonstrating that HFCS would be worse than table sugar (sucrose) (63, 64, 65). Yet, chocolate milk contains both of these additives. The fructose contained in almost equal quantities in both these additives could be linked to obesity (66, 67). Some scientists are reluctant to establish such a link (63, 64)A small quantity of fructose consumed every day, such as normal consumption of fruits, is harmless. Unfortunately, fructose is now added in almost all processed food. So it’s easy to exceed the healthy daily quantities of “natural” fructose. The body metabolises fructose differently from glucose. The liver metabolises 70% of the blood fructose (compared to 15 to 30% for the glucose) (38) and will leave the remaining 30% to the other tissues, namely the kidneys, the testicles, the fatty tissues, the brain and the skeletal muscle (69). So the muscles will absorb a negligible amount of fructose (68). A large consumption of fructose can contribute to the development of the metabolic syndrome, consisting in weight gain, increased resistance to insulin, hypertension, and elevated triglyceride in the blood stream (67, 69). High quantities of fructose are also associated to increased cholesterol, LDL particles and visceral obesity (69).

After an intense cardiovascular training, such as a marathon, when the glycogen stores in the liver are low, the fructose present in a sports nutrition supplement will be used to replenish the hepatic stores. Furthermore, for marathon runners performing at high intensities for a long period of time, the intake of fructose in the form of supplements DURING performance at a ratio of 2:1 (glucose/maltodextrin:fructose), offers a definite advantage because it allows faster absorption of sugars through the intestines since different transporters are used for these two sugars. The supplement would also improve gastro-intestinal comfort and would increase these athletes’ performance (70 to 76)If, however, the quantity of fructose consumed is higher than what is needed to replenish the hepatic stores, the surplus could potentially be converted into fat (66). So for people who do resistance training, consuming fructose is of no value. Conclusion? If you need CHO to perform well during your second strength training, you should add glucose/maltodextrin to your whey proteins, in order to avoid consuming fructose unnecessarily.

Finally, at the beginning of 2015, Stuart M. Phillips’ team established that drinking 500ml of chocolate milk every day (18g of proteins) as a supplement, while following a resistance program three times per week over a period of twelve weeks, has no effect on muscle hypertrophy or on strength gain compared to a control group taking no supplements (77).

What about after leisure endurance training?

Many active people do endurance training several times per week such as jogging, spinning, swimming, etc. for one hour. The extent of the muscle and hepatic glycogen loss will vary according to the effort expended. To consume glycogen as a primary source of energy, the level of effort intensity must reach 70% and must be maintained for an extended period of time (4, 5, 78). Laboratory experiments have shown that glycogen stores decline by 50 to 75% after 3 hours of cycling at 70% of VO2max (79, 80). By increasing the effort to 80% of VO2max, you can continue your activity for 2 hours before running out of glycogen. Another example is that the glycogen stores depletion of marathon runners occurs, for 40% of them, around the 34th kilometre, commonly called “the wall”, when they sustain an effort of approximately 80% of VO2max(81, 82, 83) during more than 2h30. Do you think you will be burning as much glycogen during your hour of spinning?

The glycogen stores lost during the training, even if this loss is significant, will be rebuilt through normal nutrition, WITHOUT ANY SUPPLEMENTS, within 24 hours of the training  (84,85). Moreover, the meal frequency will have no incidence if the post-exercise recovery happens over more than 24 hours (85, 86, 87). It is unnecessary for someone coming out of an hour of spinning or jogging to ingest all the added sugars contained in chocolate milk since the subsequent meals will contain sufficient carbohydrates (CHO) to replenish the poorly depleted glycogen stores. Therefore, the person will be ready for the next training a few days later.

Without being Olympic athletes, some people will train intensely and frequently during a week. In such case, the quantity of CHO these people consume every day must be adjusted, spread throughout their meals according to the frequency and intensity of their training. Burke et al. 2011 recommend to take a quantity of CHO every day, depending on the type of training performed (intensity and duration) to allow for a good glycogen resynthesis during the 24 hours following the training (88).

If the objectives of the person doing endurance training don’t include maximum muscular development, the muscle regeneration following an effort, namely the replenishment of glycogen stores, will occur normally with the proteins contained in the subsequent meal, when taken in sufficient quantity.

Supplements are necessary when training sessions are very intense and close together (a few hours) and require to quickly replenish the glycogen stores (in less than 24 hours).

What about high level athletes? (1.3% of the American population are athletes and of which 0.006% are professional athletes) (89).

Although chocolate milk is not intended for Olympic athletes, choosing such athletes as spokesperson to promote chocolate milk as a post-training supplement is almost an obligation; indeed, practically only these athletes could ultimately use chocolate milk as a sports nutrition supplement. Moreover, most studies carried out on the subject are done in a top level training context. But is chocolate milk, as alleged by the television commercials, a good choice for this 1% of the population ?

The purpose of a supplement is to promote fast recovery between two trainings done very close together, mainly by QUICKLY regenerating the glycogen stores. So the muscle glycogen resynthesis speed is important. It was established that this synthesis is faster when CHO are taken right after the training (90, 91, 92) and can be maintained during 6 hours with frequent intake of this supplement (69, 90, 93). Delaying the intake of CHO by 2 hours decreases the resynthesis speed by 50% (16,90). This is particularly important for a fast recovery but is unnecessary for recovery over 24 hours or more (87). OPTIMALLY, the quantity of CHO should be 1.0 to 1.2g/kg of weight/h (94, 95, 96), consumed at 15 to 30 min intervals (97). At this volume and frequency, CHO alone are sufficient to ensure an optimal glycogen synthesis. Sure! But chocolate milk doesn’t only contain CHO!

Is it useful to add proteins to CHO? (98)

To determine which supplement is the best one, we need to compare the different supplements. It is difficult to compare the studies that analyze the effect of adding proteins to a CHO supplement because several variables differ: 1) intensity (% of VO2max) and duration of the first exercise that aims at reducing the glycogen stores 2) choice of exercise (jogging or cycling) 3) various types of supplements consumed (isocaloric or not, as well as the chosen sugars and proteins) 4) control groups used (lack of placebo or other control groups) 5) carbohydrates:protein ratios (CHO:PRO) will vary between 2:1 (Berardi et al. 2006/2008) (99, 100) and 6.2:1 (Betts et al. 2005) (101) 6) duration and intensity of the second performance (% of VO2max).

Nonetheless, it’s possible to draw certain conclusions.

1: Importantly, the drinks studied must be isocaloric (must contain the same amount of calories) :

Some studies show a performance improvement post-recovery when proteins (PRO) are added to CHO versus a control group taking only CHO (102 to 105). However, the quantity of calories between the two drinks was not adjusted, so it wasn’t possible to determine if the performance improvement could be attributed to the addition of proteins or to the aaddition of energy.

2: It is important to compare the CHO+PRO supplement to a control group taking CHO optimally (1.0 to 1.2g/kg of weight/h) AND which is isocaloric:

Some studies show that the addition of proteins to the CHO supplement improves the second performance when compared to a control group taking a CHO only supplement. But this supplement was given sub-optimally during recovery (96, 102, 104, 106, 107). When the control group took the CHO supplement OPTIMALLY, the studies did not show any improvement in the second performance when proteins were added to the mix, even with variable ratios. (95, 96, 101 to 115, 116). A study showed, however, an advantage (100) (see the “Ratio” section).

So the athlete can chose between taking a mix of CHO + PRO, when it is impossible to optimally take a CHO supplement during recovery (1.2g/kg/h every 30 min during 3 to 4 hours) (94, 95, 96, 117). This indeed makes for a lot of CHO to ingest. But at which ratio must the athlete take its proteins?

3: Ratio

Advocates of chocolate milk allege that a ratio of 4:1 is best to support athletic recovery. This belief comes from one of the early studies done on the subject and which showed that a sports nutrition supplement, Endurox R4, containing 4:1 CHO: PRO offered a performance advantage when compared to a control group taking CHO, namely Gatorade (102). However, Endurox R4 contained two and a half times more CHO than Gatorade, in addition to the whey proteins, which gave it almost four times more calories than the Gatorade supplement consumed SUB-OPTIMALLY by the participants. It is obvious that in these conditions, Endurox R4 improved performance compared to Gatorade given the significant difference in CHO and energy consumed between the two drinks. Since the ratio used in this study was 4:1, which is the same as the chocolate milk ratio, the dairy industry took the opportunity to pretend it was the best ratio. Nonetheless, research continued and more recent studies show that ratios containing less sugar are as efficient, if not more, than a 4:1 ratio. Berardi et al. 2008 show an advantage on the second performance with the CHO: PRO mix at a ratio of 2:1 (CHO: 0.8kg/kg/hand PRO: 0.4kg/kg/h), over the control group taking the CHO supplement optimally (100, 117). So why add more sugar than necessary with a ratio of 4:1 if it offers no advantage?

 

Studies done on chocolate milk (McLellan TM et al. 2014 (98)) :

There are 5 major studies comparing chocolate milk to a few other sports drinks during a short term recovery between two performances. (118, 119, 120, 121, 122)

  • None of these 5 studies explained how the chocolate milk taste was reproduced for the control groups. If the athletes know which type of supplement they are given, it can certainly influence the results; in such a case, the study is no longer “blind”.
  • Some studies did not include a placebo or a sub-optimal CHO supplement for the control group (118, 122).
  • 4 studies on 5 did not administer the supplement optimally (118, 119, 120, 121). The fifth study did so for the first recovery hour only (122).
  • Pritchett et al. 2009 show that chocolate milk (3.8:1) offers no advantage for the second performance over Endurox R4 (3.8:1, isocaloric and same quantity of CHO) (118).
  • The other four studies indicated that chocolate milk presented an advantage for the second performance compared to the other drinks studied (119, 120, 121, 122). On the other hand, the studies also present other shortfalls:

For Karp et al. 2006 and Thomas et al. 2009, the glycogen stores reduction protocol was not standardized during the first training(119, 120). That means that the energy expenditure varies a lot from one person to another, even for each individual, from one training session to another. So some groups used more glycogen than others before starting the recovery phase. For Karp et al. 2006 for example, (similar to Thomas et al. 2009), the chocolate milk group (60.8 min) had trained 16% less than the CHO + PRO control group taking Endurox R4 (72.6 min), but equally to the Gatorade group (sub-optimal). These differences can explain the superior performance of the chocolate milk group during the second training. Furthermore, we must report that the study by Karp et al. 2006 was partly financed by the Dairy and Nutrition Council Inc (119).

In the study by Lunn et al. 2012, chocolate milk is compared to a control group taking CHO optimally during the first hour of recovery (122). Despite the fact that the regeneration of the glycogen stores was equal between the two groups, the performance of the chocolate milk group was superior to that of the CHO control group during the second performance (difference of a few seconds). However, the intensity of the second performance was at 100% VO2max and lasted a very short time (203 vs 250 sec). In these very high intensity and very short duration conditions, the more or less important level of muscle glycogen stores before the effort don’t seem to influence performance (123, 124, 125, 126), as opposed to a lower intensity and longer duration performance. So optimally replenishing the glycogen stores is probably not that important in this case. Even the authors admit that the type of test used and the inability to mask the taste of the chocolate milk may have influenced the results. The authors challenge this by emphasizing that the purpose of their study was to show that chocolate milk promotes a better muscle synthesis compared to CHO alone (122). Milk contains proteins whereas the CHO of the control group contained none. So it is not surprising that the results show that chocolate milk increases muscle synthesis. A control group also taking proteins would have certainly given results similar to the chocolate milk, and possibly even better results if whey protein would have been used.

 The study by Furguson-Stegall et al. 2011 compared a chocolate milk ratio smaller than 3:1 to an isocaloric CHO drink and to a placebo (water) (121). The drinks were given sub-optimally. The performance of the chocolate milk group was superior by a few minutes during the second training (40km of cycling) compared to the CHO control group. Nonetheless, the glycogen resynthesis was better with the CHO control group, a result that is slightly contradictory. This study was financed by a Chair established by The National Dairy Council, as well as The National Fluid Milk Processor Promotion Board.

Therefore, the contradictory results, the lack of control groups, the questionable protocols and the inability to obtain blinded studies, do not allow to claim without any doubt that chocolate milk is the best supplement compared to the other supplements studied. The number of serious studies on chocolate milk will have to be considerably larger. Furthermore, these studies will have to be done more independently (not financed by the dairy industry, for example) to achieve more conclusive results.

It should be noted that chocolate milk has not been compared to a supplement offering a ratio of 2:1 previously shown to offer better performances than a CHO supplement taken optimally by Berardi et al. 2008 (100). For comparison purposes, a 200lbs (90kg) man who ingests a supplement offering a ratio of 2:1 will consume 72g of CHO/h instead of 85g/h for a chocolate milk supplement taken optimally. So this represents approximately 40g less of added sugar consumed, during a 3 hour recovery, to achieve the same result, if not better.

The composition of the supplement used by Berardi et al. 2008 is also very different from that of chocolate milk; it contained 33% of maltodextrin, 33% of glucose and 33% of whey (100). So in addition to the ratio, the choice of nutrients is important.

4: CHO

Maltodextrin (MD) seems to be the ideal sugar for muscle glycogen resynthesis after an intense effort. Piehl-Aulin et al. 2000 have shown that a supplement containing very high molecular weight polyglucosides such as maltodextrin would be 25% more efficient for muscle glycogen synthesis than a low molecular weight glucose, maltose or oligomer supplement (127). This would be due to the faster absorption rate of sugars by the intestines, as well as an increased rate of gastric emptying. As seen previously, while the addition of fructose to MD (ratio 2:1, MD: FRU) represents a major advantage DURING a long performance (more than 2h30) such as a marathon(128), it seems that for the rapid muscle glycogen resynthesis between two performances, the addition of fructose or galactose to MD offers no advantage (129). Regarding sucrose (glucose: fructose), no advantage was observed concerning glycogen resynthesis when compared to glucose alone (69, 129, 130, 131, 132), nor during the second performance (129 to 131). Again, we notice that the fructose and galactose portion found in chocolate milk is not useful for the post-training recovery.

5: Proteins

As for strength training, the type of proteins added to the CHO as a post-training supplement is important. However, few studies compare the different types of proteins and their effects on the glycogen resynthesis speed during a short term recovery. Morifuji et al. 2010 have shown, in rats, that adding whey hydrolysate to CHO is more efficient for glycogen synthesis than the CHO control group, followed by non-hydrolysed whey and BCAA. Casein ranked dead last, having no significant effect on glycogen synthesis compared to the intake of glucose alone (133). A large proportion of studies on athletic recovery used hydrolysed or non-hydrolysed whey protein isolate as a source of proteins in their mixes. The advantage over the chocolate milk proteins (mainly consisting of casein) is that in addition to being absorbed faster, the whey protein allows a higher protein concentration mix while restricting the volume to be consumed. It is a non-negligible advantage for the athletes as well as for achieving ratios of 2:1, for example.

Lactose

Milk contains 25g of lactose per 500ml. The capacity to break down lactose into glucose and galactose molecules depends on the presence of the lactase enzyme in the small intestine. “Normally” in humans, the presence or activity of lactase is very strong at the beginning of childhood and starts declining after the child is weaned until it almost disappears in adulthood. The person is then unable to digest lactose for the rest of his or her life (134, 135, 136). Between 65 and 70% of the world population is unable to digest lactose once they reach adulthood (137, 138). So only 30 to 35% of the population can actually digest lactose. Why? During the human evolution, four different mutations occurred, namely a major one that occurred in Europe, which kept the lactase gene active and thus allowing some Caucasians to digest lactose during all their life(137 to 139). These European Caucasians travelled, reached America and gave their descendants the possibility to also carry this mutation. Despite this, approximately 21% of North Americans who have problems digesting lactose are Caucasians (140). The ability to digest lactose is directly linked to the quantity of lactase produced by the intestine (134 to 136) and this quantity varies from one person to another. So some people have more difficulty than others to digest this sugar even though it may not be a true intolerance, rather an incomplete digestion that can sometimes be asymptomatic (140 to 143).

Making up 50% of the sugar contained in chocolate milk, we must seriously question the lactose digestion capacity to quickly regenerate the glycogen stores post-training, if we take into account the differences in the quantities of lactase present in the intestines of each individuals. It was shown that adding sugar (144, 145, 146, 147), fat (147) or chocolate (144, 145) in milk slows down the digestion process. This slowing down certainly promotes a better digestion of the lactose by the lactase present in various amounts, but does make digestion more efficient ? Since it can be very difficult for some people, around the world, to digest lactose, chocolate milk could only be used by a very small portion of athletes, which already represent a tiny portion of the population.

Who promotes chocolate milk?

Besides dairy producers in Quebec and Canada, many nutritionists promote chocolate milk as an ideal post-training supplement. The most relevant comment made to this effect by a nutritionist is the comment from Isabelle Charêt, coach and triple medallist in speed skating at the 1994, 1998 and 2002 winter Olympics (148). She says that chocolate milk would be a lot more useful to people who train intensively: “Someone who goes to the gym three times a week has plenty of time to recover. But I still recommend to drink chocolate milk because people in general don’t drink enough milk.” Ah! But that’s the issue! We have to drink milk!

I will not go into further detail on this subject, but very recently (2013), a team from Harvard University acknowledged publicly the need to decrease to less than two portions per day, or to stop all together, our milk consumption (149, 150). The powerful dairy industry lobby, which represents a third of Quebec’s agriculture and 5 billion dollars of Canadian GDP, imposed itself to maintain the dominant position dairy products hold in the Canadian food guide (151). Nonetheless, the following question remains: is it necessary to include chocolate milk in our diet? Many scientists seem to think that it’s not (149, 150, 151, 152).

Conscious of the extent of the damages caused by the overconsumption of added sugars to human health, how can we encourage the consumption of such sugars just to impose a supplement that is increasingly considered as unnecessary to our health?

Conclusion? If you enjoy a glass of chocolate milk once in a while, as a treat, it’s no big deal! But if milk commercials encourage you to drink one after each of your trainings, and you are not an Olympic athlete (and even then…), I hope you’ll think twice about it.

You know the saying: When it seems too good to be true…

 

References :

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10.    Roy BD, Tarnopolsky MA, MacDougall JD et al. (1997). Effect of glucose supplement timing on protein metabolism after resistance training. J Appl Physiol. 82 :1882-1888

11.    MacDougall JD, Ray S, McCartney N, et al. (1999). Muscle substrate utilization and lactate production during weight lifting. Can J Appl Physiol. 24(3) :209-215.

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