Figure 7. Depiction of the Knee Extensor Force-Velocity Relationship.

The force-velocity relationship for the quadriceps produces maximal concentric knee extension force/torque at slow contraction velocities (i.e., maximal effort pushing/overcoming isometric contractions or concentric contractions at < 60 degrees/second).⁹³ Partially due to residual force enhancement during eccentric contractions (i.e., active muscle lengthening at maximal effort), maximal knee extension force/torque-output will be higher during eccentric than concentric contractions.⁹⁴ %, percentage; 1-RM_(con), 1-repitition maximum during a concentric contraction; deg, degrees; RFE, residual force enhancement; sec, second.