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Qualitative Torque Analysis Line of gravity positioned over instep Three joint torques are created from this line of gravity Ankles: Plantar Flexion Knees: Extension Hip Extension Feet push down into floor creates a vertical reactive force moving body and weight upward Examples Olympic-style front squat (diagram 1 above) Barbell positioned infront of body Torso more upright Relatively high knee torque (at bottom position) Bodybuilding-style squat (diagram 2 above) Barbell positioned high on shoulders Torso moderately sloped Torques more moderately distributed between knee and hip Powerlifting-style squat Barbell positioned low behind shoulders Torso highly sloped Relatively high hip torque Box Squat Participant sits back on box Very low knee torque Also see Squat Analysis Other Compound Exercises Torque forces equally distributed through multiple joints Synergistic mechanics Greatest gross force production through true compound mechanics Exposes kinetics chain to particular forces necessary for adaptation See Adaptation Criteria Torque forces shifted toward target joints Emphasizes target muscle group or joint movement Decrease torque forces through venerable joint Too great a "torque shift" Decreases involvement of muscles involved through adjacent joint Basic exercise turns into auxiliary exercise May decrease gross force production of exercise Mechanics begin to resemble isolated exercises May decrease range of motion of both joints Examples Extra-wide grip bench press or Guillotine Bench Press Leg Press with feet very high on platform Subtle torque shifts (if any) may be more beneficial than more drastic torque shifts since greater weights can be used thereby increasing overall strength performance. Sports Conditioning Exercises should mimic biomechanics practiced in activity Coaches prescribe the powerlifting squat (wide stance, bar low on back, little knee torque) often excluding exercises with greater knee torque Olympic-style front squat Bodybuilding style squat Rationale is Glutes are stonger than Quads So should we ignor Quad strength? See Squat Analysis Also see Resistance Training for the Reduction of Sports Injury Specific Adaptation Training Specificity Range of Motion Sports Conditioning