Computer simulations show that when lifting very heavy weights in a squat, the hip and knee joints reach their maximum ability to generate force, while the ankle joint does not, suggesting that...
Mechanism
Synthesis from 1 study
When you squat with a very heavy bar, your hips and knees can barely handle the force, so your body leans forward to stay balanced. Your ankles aren’t strained because they can still handle more — so they don’t limit how you move.
Most probable mechanism
When you squat with very heavy weight, your hips and knees reach the maximum force they can produce, so your body shifts forward to keep balance, while your ankles don’t get pushed to their limit because they can still handle more force.
Under heavy external load, the torque demands at the hip and knee joints approach the maximum rotational force their musculature and connective tissues can generate.
As hip and knee moment capacity is approached, the center of mass shifts anteriorly to maintain equilibrium, altering trunk and limb positioning during the descent phase.
The ankle joint experiences significantly lower torque demands relative to its maximum capacity, allowing it to remain within its mechanical buffer without limiting movement.
Evidence from Studies
Supporting (1)
Community contributions welcome
Numerical Modeling of Load-Driven Changes in Squat Technique Using a Moment-Limited Joint Framework
Contradicting (0)
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