Speed: What Actually Makes Someone Faster

Speed is produced by several underlying adaptations, and each requires a different type of stimulus.

Coordination is one of the most specific. To improve the coordination of a fast movement, that movement has to be practiced quickly. Slow practice does not fully develop the motor program required at maximal velocity. This is why sprinting, jumping, throwing, or other high-speed tasks need to be performed at or near the speed the athlete is trying to improve.

The quality of each repetition matters. Once fatigue causes the athlete to slow down, the training stimulus changes. High-velocity work therefore does not need to follow traditional high-volume set-and-rep structures. A small number of maximal-quality repetitions may be more useful than continuing after velocity has fallen.

Motor-unit recruitment is different because it is primarily muscle-specific rather than movement-specific. Heavy strength training and brief maximal isometrics can improve recruitment and contribute to faster performance even though those exercises are not performed at maximal velocity.

Other adaptations, however, require actual fast movement. Increased motor-unit firing rates and increased muscle-fiber shortening velocity do not appear to develop from heavy strength training alone. They require genuinely high movement speeds. Maximal intent with a slowly moving heavy load is therefore not a substitute for fast training.

Strength work can also interfere with speed when poorly managed. Excessive fatigue can promote shifts toward slower muscle-fiber characteristics, and unnecessary hypertrophy can add mass that the athlete then has to accelerate and decelerate. This is especially relevant when muscle is added distally rather than around the hips.

Actionable takeaway: Train speed through three main targets: practice the actual fast movement for coordination, use heavy work or brief isometrics to improve transferable recruitment, and include genuinely maximal-velocity work to improve firing rate and shortening velocity. Stop the work when speed begins to fall.

Maximum Strength: What Actually Makes Someone Stronger

Maximum strength can improve through several different adaptations, and those adaptations do not all transfer equally to other movements.

Coordination is one contributor. Repeated practice can make an exercise more efficient, allowing someone to lift more weight without necessarily increasing the force-producing capacity of the muscle itself. This type of improvement is highly specific to the movement and even to the load being used. Becoming more skilled at a heavy squat is therefore very useful for a powerlifter, but that coordination does not automatically transfer to sprinting or jumping.

Motor-unit recruitment is much more transferable. Improving the nervous system’s ability to activate more of a muscle increases the force that muscle can produce across different movements that use it. High recruitment can be trained through heavy lifting, brief maximal isometrics, and other high-effort contractions, provided fatigue and discomfort are kept low enough to allow high central motor command.

Hypertrophy contributes by increasing the amount of contractile tissue available to produce force. For athletes, however, the location of that muscle matters. Adding muscle where it contributes to the demands of the sport can be useful, while adding mass indiscriminately may not be.

Other adaptations can also contribute. Reduced antagonist co-activation can increase net force around a joint. Lateral force transmission can improve how efficiently muscle-fiber force reaches the tendon. Increased tendon stiffness can improve force production in slow, high-force actions by changing how quickly the muscle fibers themselves have to shorten.

The important point is that the same improvement in a strength test can come from very different mechanisms.

Actionable takeaway: Do not treat “getting stronger” as one process. Identify whether the goal is movement skill, greater muscle activation, more muscle, or another force-producing adaptation, and program specifically for that need.