Fig. (2) Percent change in FaclMAX due to changes in the following anatomical and physiological parameters: moment arms of the patellar tendon (ptma), gastrocnemius at the knee (gkma), and ankle (gama), initial hamstring (hmao) and change in hamstring angle (Δhma); ACL stiffness (acls); nonlinear activation parameters (nap); tibial slope (Φtf ); initial line of force of the hamstring (Φhamo) initial patellar tendon line of force (Φpat), rate of change in the hamstring angle (ΔΦham) with knee flexion, and rate of change in the patellar tendon line of force (ΔΦpat) with knee flexion. Distance measures were changed by ±5%. Angular measures were changed by 0.05 radians (±2.9°). Δhma, ΔΦham, and ΔΦpat are with respect to change in knee flexion, initial values at those at full knee extension.