Mechanics In Exercise

Alignment

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Alignment Position body segments according to anatomical principles and Functional conditioning Kinetic chain Plane of motion in line with force vector Rotary motion(s) of target muscle group(s) oppose(s) resistive force Supporting chain Posture conducive to function and safety Position for stability Adjust body orientation target desired muscle groups modify angle of pull conducive to training objectives Take note of subtle difference of postures and movements effect on joint and muscle involvement effect on efficacy, safety, and specific adaptation Analysis and correction Coaching and Training Address Biomechanical Deficiencies which may effect ideal exercise form Visual and kinesthetic feedback Isolated Lever machines Ridged Lever Align pivot point of joint with the machine's fulcrum. e.g.: Lever Leg Curl Understand Scapulohumeral Rhythm when aligning machine's fulcrum with exercises involving shoulder girdle e.g.: Lever Lateral Raise, Lever Pullover Accommodating Secondary Lever or Roller Pivot point of joint may not have to be positioned exactly in line with machine's primary fulcrum Secondary lever or roller will dynamically articulate to accommodate varying lever body segment lengths and positions Roller example Lever Leg Extension Accommodating secondary lever examples: Cybex arm curl (a.k.a. Lever Preacher Curl) Cybex Triceps Extension Cybex Eagle Triceps Extension 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 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 See Squat Analysis Coaches emphasize bench press for upper body strength In actuality, upper body training should emphasis the Jerk or Military Press and Incline Bench Press Pushing while blocking is performed with the body angled into the opponent to maintain balance while maximizing force (See Factors Increasing Stability) Not upright with arms at a transverse plane (like Frankenstein running at you) Also see Resistance Training for the Reduction of Sports Injury Specific Adaptation Training Specificity Range of Motion Sports Conditioning