Common Resistance Training Mistakes

Force Vector and Alignment Errors

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Dumbbell Shoulder External Rotation Errors (upright posture) Target muscle moves body segment through plane perpendicular to resistance Force must be through the transverse plane lying on side cable surgical or exercise tubing Correct form Dumbbell (lying) Cable (standing) Bottom line: with a dumbbell, perform this exercise lying on your side Dumbbell Triceps Kickback Errors (elbow too low) Effective range of motion decreased by drop in elbow Triceps Kickback (correct form) already has half the effective range of motion as other triceps exercises greatest resistance occurs at full extension when weight travels parallel to gravity See Gravity Vector and diagram Peak contraction If elbow is too low (see animation to right) very little effective range of motion exerciser typically tries to compensate and flexes arm against gravity performing something that resembles a hammer curl even that motion compromises range of motion. resistance does not travel parallel to gravity at end of motion less weight is needed possible causes weight could be too great exerciser is not bent over enough upper arm need to be positioned horizontal exerciser merely tries to bend over slightly (typically without arm support) thinking that will do. Shoulder Shrugs Errors (shoulder rolls) Rolling (horizontal movement) is nonsensical Weight moves perpendicular to gravity In an upright posture, the upper traps and middle traps resist weights against gravity (downward force) as they elevate the scapula see correct form Although it is true the middle and lower trapezius can also retract the scapula on a continuum of planes they resist such a load retracting against a resistance on a transverse plane during general back exercises or by upward rotation on a frontal plane during shoulder exercises Bottom line: It's only necessary to raise and lower the shoulders during shrugs. The lower and middle trapezius will be exercised during other basic exercises Also see ROM Criteria Cable Exercise Errors (cable perpendicular to line of force) Added resistance through cable (weight stack via pulley) is aligned perpendicular to target muscles does not effect difficulty of exercise no or little movement of weight stack during key motion of exercise Correct form: pull of cable needs to travel: relatively vertical under exerciser e.g.: Cable Squat approximately parallel with line of push e.g.: Cable Lunge Some so called exercise experts evidentally even fail to understand this important biomechanical concept For example, Hammer Strength Training Vest exercise video demonstrates numberous movements that load exercises perpendicular to line of force of synergist muscles. Compound Wide Grip Upper Body Exercise Errors (too wide of grip) Recommended grip width for wide grip exercises elbow width, when elbow is same height/plane as shoulders subtle deviations may still be used (i.e. 2 cm narrower or wider) Wider grip decreases range of motion through shoulder when elbow is extended through elbow when shoulder is in transverse extension or adduction decreases relative involvement of assisting muscles turns basic exercise into auxiliary exercise may as well implement auxiliary exercise through fuller range of motion Example wide grip exercises Bench Press Incline Bench Press Pulldown Chin-up | Pull-up Shoulder Press Also see Dip Bar Width Line drawings from Trainer ClipArt.

Lateral Raise Errors (shoulder external rotation) Shoulder external rotation If dynamic shoulder external rotation occurs during lift Infraspinatus and Teres Minor become primary mover Shoulder external rotation can be confused with shoulder abduction little shoulder abduction is actually occurring despite weight being raised If static shoulder external rotation is maintained throughout movement Shoulder is not kept externally rotated. ie: elbows drops below wrist Anterior Deltoid becomes primary mover In either case, Lateral Deltoid involvement is dramatically decreased. Purpose of movement is defeated Other more effective exercises may as well be used to exercise these muscles that are unintended exercised. Shoulder Extension Elbows travel behind shoulders lessened emphasis of lateral deltoid Correct form: At top of movement, elbows (not necessarily dumbbells) should be directly lateral to shoulders since elbows are slightly bent forward. Throwing weight up Decreases deltoid involvement particularly if momentum originates from sudden extension of hip or spine. Complete upright position Line of pull can be shifted to anterior deltoid unless extreme internal shoulder rotation is executed See correct form Rear Lateral Raise Errors (shoulder extension or external rotation) When elbows travel under shoulders Latissimus Dorsi takes the majority of the load Shoulder extension Rear delts are still exercised Forfeits the purpose of even performing an auxiliary isolated movement Isolation Lats can be exercised more efficiently with rows and pull-downs Trainees typically require feedback by mirror if not by a trained coach to determine if their arms are following the correct path Shoulder external rotation Rear delts do assist in external rotation but performing the exercise correctly will work target muscle more effectively Additional flaws Weight is typically thrown up Weight travels parallel to gravity at end of contraction See Gravity Vector and diagram Peak contraction Lighter weight should be used so it can be lifted without excessive momentum Elbows bent too much Shorter lever arm means less force (See Lever Arm Length) Use less weight so arm is only slightly bent Low back is rounded Although knees are bent to allow greater flexion through hips, the back should be straight May be corrected with coaching if hamstrings are adequately flexible See Barbell Bent-over Row Comments Correct form Elbows directly lateral to shoulder at top position Upper arms travel perpendicular to body Practically no Latissimus Dorsi involvement Weight should be lifted with control Elbows should not be bent too much Lower back straight Low Back Alignment Exceptions Guidelines recommended for particular exercises may not apply to certain exercises Example Dumbbell Bent-over row practically no torque on low back since torso is supported by arm bend in spine may be overlooked since it presents no risk Dumbbell Seated Rear Lateral Raise little torque on low back since thighs provide support for torso bend in spine may be overlooked since it provides little risk Straight Leg Deadlift and Cable Row with articulating spine exercises that intentionally exercise the spinal erectors through a full range of motion spinal extension in a controlled systematic manor See Dangerous Exercise Essay and Low Back Debate Individuals with certain injuries or predisposition to injury may need to take additional precautions.