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Do Cheating Reps Reduce Muscle Gains and Cause Injuries?

Everyone always talks about how strict your form should be when lifting. Bad form can hurt you if you round your back during a squat, row, or other exercise. But what if you cheat a little, like using a bit of swing during a curl or leaning back more on a lat pulldown? Is cheating once in a while really that bad?

Here's my answer.

I must admit that a little bit of controlled cheating is not only acceptable and safe if you are smart about it, but this loose form may help you gain more muscle than a really rigorous form.

That could come out as heretical as it's common knowledge that lifting weights requires precise form in order to maximize muscular development and prevent injury.

The idea is that you lose gains if you swing a weight up or employ improper form because momentum pushes the weight rather than more muscular activation and other muscles assist. Less stimulation and consequent development are therefore received by the targeted muscle.

This argument to do your reps strictly has been supported by studies published in the Journal of Sports Medicine and Exercise.

There were 3 main comments:

1. Lift at a pace (tempo) that allows you to keep tension throughout the whole range of motion.

2. The muscles are released of tension when ballistic and quick activities are performed.

3. Ballistically and quickly performing exercises (such as Olympic lifting and plyometrics) increases the stress applied to the joints and connective tissues, which raises the possibility of damage.

Despite its apparent common sense, people persistently advocate for strict adherence to proper form.

Some of the most successful bodybuilders and those with well-developed physiques sometimes use less strict form.

You may see this directly in the gym these days and on well-known bodybuilder You Tube channels. Go back even further to the renowned Pumping Iron DVD to witness Arnold and his peers employing a great deal of body language while lifting.

It's not, however, just "what the bros do" vs "what the research says." Some scientifically informed training recommendations, as I indicated, advise against employing momentum. Still other study points to a place for "cheating." That is so due to the complexity of this subject.

When I inform them that there has been legitimate scientific study on cheating reps, some are taken aback. Actually, a highly referenced study was titled "Does cheating pay: the role or externally supplied momentum on muscular force in resistance exercise."

The exercise scientists in this work sought to determine how using motion while lifting would affect muscle stimulation. They went with the dumbbell lateral raise exercise, which I believe was a great decision for this sort of test. A lateral rise done strictly and one done somewhat loosely differ greatly.

They coupled earlier study findings with an examination of muscle recruitment, biomechanics, and anthropometric measures. Using momentum at the beginning of a repetition, they discovered, enhanced the torque generated on each iteration.

The optimal balance between safety, time under stress, and overall tension in the target muscles engaged in the lateral rise is found, they found, when a little momentum is applied at the beginning of each repetition.

This basically indicates that there is in fact less tension on the target muscle if you swing or sway your body (momentum) to heave up a bigger weight than you normally would. But if you merely apply a little momentum at the beginning of the repetition, the extra weight you can lift allows you to apply more overload, which more than offsets any drawbacks.

Examining things from the other perspective as well. Use of extremely light weights is required if you attempt to use extremely strict form without the slightest degree of velocity. You can use far more weight in a rep with a little bit of momentum at the beginning than you can in an extremely strict rep.

Greater overload can also be achieved by using a little amount of motion to raise a weight and then regulate the lowering (eccentric/negative) part of the repetition.

It appears from science that a little restrained cheating is not only acceptable but sometimes even preferable to a very stringent reg. Disclaimers apply, though. The most evident is that there are more disadvantages than advantages if cheating is done excessively. Target muscle activation decreases with increase of injury risk.

The research has other restrictions as well. Actually muscle gain over time was not measured in this specific study. It solely tracked momentary results like muscle activation and torque. Still, there has been study done on a related subject: repetition speed.

Generally speaking, doing exercises incredibly quickly is seen as more like cheating, while doing them really slowly is seen as harsher. Yet a study by Brad Schoenfeld and colleagues found that if the volume load was the same, the muscular growth were identical regardless of whether the rep speed was anywhere between a half a second to 8 seconds.

This would imply that the rep speed is not as crucial as many people used to think. Muscle can be gained provided you can move that weight from point A to point B without using too much momentum.

Naturally, one of the most important warnings is to never let your form become so loose that you run the danger of getting hurt. On some workouts, this is a greater worry than on others. When little momentum is applied to exercises like lat pulldowns, lateral raises, and bicep curls, the risk of injury is rather modest. Doing a bench press with a barbell bouncing off your chest is foolish.

We also refer to employing a small bit of momentum when we discuss somewhat cheating or slightly loose form. We're not discussing poor body mechanics or postures like rounding your back during a row or deadlift. You run the danger of injury even if you lift gently and without momentum if you performed the exercise incorrectly in the first place.

Finally, it's likely that observing the ripped guys in the gym alone could mislead you. More than their exercise regimen, the guys may have benefited from "special supplements" and heredity. And it could be difficult to present a really compelling argument if you merely examined a few scientific studies.

However, I believe it is reasonable to state that a little controlled cheating or loose form is acceptable and, if done wisely, is probably preferable than trying to be too rigorous if you consider the studies, however limited, together with actual results.



My name is Steven Goldstein

With over 10 years of experience in the fitness industry, I have worked with clients of all ages and fitness levels. From professional athletes to individuals aiming to lose weight, I have helped countless people achieve their goals and improve their overall health through customized training and nutrition plans.

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