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.