Common Resistance Training Mistakes

Force Vector and Alignment Errors

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It is important to have at least a basic understand the mechanics of an exercise you intend to perform or teach, whether it's a weight training or flexibility exercise. Exercises require particular positioning of the body in order for target muscle groups(s) to be exercised optimally.

You can't just put a weight on top of you head, rotate your head side to side, and call it a neck rotation exercise. Progressive resistance torque needs to be applied by situating the load against a force (commonly weights via gravity) so that the intended movement, or target muscles are challenged throughout a target range of motion, typically throughout full range.

Upright Bench Press?For a better understanding this concept, let's begin with another ridiculous example of someone attempting to perform a Barbell Bench Press, but standing upright instead of lying supine. The pectoralis muscles, after all, are suited for drawing the arms forward and inward across the chest (transverse adduction). The movement is correct. So why would not this exercise work? The other crucial requirement obviously involves the alignment of target muscles against the resistive force. In the case of free weights that force is gravity pulling downward. This means if we are to exercises the desired muscle groups in this movement, we must orientate our body supine on a bench so our muscles contract under the force of gravity acting upon the weight.

However with machines we can alter the direction of force. Gravity still acts on the weight but the machine alters direction of force via use of lever(s) or cable pulley(s). This means on lever chest press machine, for example, we would need to be upright with the hands behind the lever handles to work these same muscles. In any case, the alignment of target muscles must be positioned against the resistive forces, which ever direction they happen to be orientated.

If we want to target the upper chest (clavicular head) on some sort of barbell press, we would need to know the action of this muscle and position our body and its appendages accordingly. In this case we would lie on an incline bench, instead of a flat bench. We would however still need to push the weight upward against gravity as we do in the Barbell Incline Bench Press. Notice the similarities and differences when we perform the Cable Standing Incline Chest Press targeting the same muscle group but using a specific positioning on an adjustable dual cable apparatus to alter the direction of force.

Other subtle variations to the body's alignment or it's appendages can make the difference between targeting the muscles or working an entirely different set of muscles. In other cases with less than ideal alignment, the target muscle may still be exercised somewhat, but likely not as nearly as effectively as a more ideal positioning would allow.

Here are some common alignment errors involving some obvious and not so obvious examples:

Dumbbell Shoulder External Rotation Errors (upright posture)

Dumbbell Shoulder External Rotation Errors

  • Target muscle moves body segment through plane perpendicular to resistance
  • Force must be through the transverse plane
  • Correct form
  • Bottom line: with a dumbbell, perform this exercise lying on your side

Dumbbell Triceps Kickback Errors (elbow too low)

Dumbbell Triceps Kickback Errors

  • 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
  • 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)

Shoulder Shrugs Errors

  • 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
  • Although it is true the middle and lower trapezius can also retract the scapula on a continuum of planes
  • 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)

Drawing from Trainer ClipArt

  • 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
      • approximately parallel with line of push
  • Some so called exercise experts evidently even fail to understand this important biomechanical concept
    • For example, Hammer Strength Training Vest exercise video demonstrates numerous movements that load exercises perpendicular to line of force of synergist muscles.

Compound Wide Grip Upper Body Exercise Errors (too wide of grip)

Drawing from Trainer ClipArt

Above line drawings from Trainer ClipArt.

Lateral Raise Errors (shoulder external rotation)

Lateral Raise ErrorsLateral Raise Errors

  • Shoulder external rotation
    • If dynamic shoulder external rotation occurs during lift
    • 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)

Rear Lateral Raise Errors: shoulder extension

  • 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

Rear Lateral Raise Errors: Shoulder external rotation

  • 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
      • 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
  • 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

  • Proper lifting guidelines regarding splinting the spine (keeping back straight) or lifting with the legs may not necessarily apply to certain exercises.
  • Individuals with certain injuries or predisposition to injury may need to take additional precautions.


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