Cheat Reps
Does a little added momentum help or hurt muscle gains?
This first-of-its-kind study, called "Do cheaters prosper? Effect of externally supplied momentum during resistance training on measures of upper body muscle hypertrophy," investigated the impact of using external momentum ("cheat" repetitions) versus strict form during resistance training on muscle growth.
Key Points
The study compared strict form (STRICT) to externally applied momentum (CHEAT) in biceps curls and triceps pushdowns.
30 young adults participated in a within-participant design, with each arm randomly assigned to either STRICT or CHEAT condition.
The training protocol lasted 8 weeks, with participants performing 4 sets of 8-12 repetitions to failure, twice a week.
Aim
The primary objective was to examine the effect of externally applied momentum on resistance training-induced muscle hypertrophy of the upper body extremities in untrained men and women.
Methods
Participants: 30 untrained male and female volunteers aged 18-40 years.
Exercises: Unilateral supinated dumbbell biceps curl and unilateral pronated cable triceps pushdown.
Training protocol: 2 non-consecutive days per week for 8 weeks, 4 sets of 8-12 repetitions to failure.
Measurements: Muscle thickness (MT) using ultrasound imaging at proximal and distal sites of elbow flexors and extensors, and upper arm circumference.
Analysis: Bayesian framework with univariate and multivariate mixed effect models.
Results
Similar increases in muscle thickness were observed for all measurement sites between STRICT and CHEAT conditions.
Upper arm circumference changes were comparable between conditions.
Volume load was significantly greater for CHEAT than STRICT across each intervention week.
Statistical analysis consistently supported the null hypothesis, indicating no significant differences between conditions (Bayes Factors ranging from 0.06 to 0.61).
Practical Application
The study suggests that using external momentum during single-joint resistance training of the upper extremities neither helps nor hinders muscle hypertrophy of the target muscles. This finding challenges the belief that strict form is always superior for muscle growth.
Key Takeaways
Contrary to the initial hypothesis, using external momentum did not have a detrimental effect on muscular adaptations.
Using "cheat" repetitions may allow for a higher volume load without compromising muscle growth.
For untrained individuals, both strict and "cheat" repetitions can be effective for muscle hypertrophy in upper body exercises.
The study's findings may have implications for exercise prescription, particularly for individuals who struggle with strict form or those aiming to increase training volume.
This research provides valuable insights into the effects of exercise technique on muscle hypertrophy, challenging some conventional wisdom in resistance training. However, it's important to note that the study focused on untrained individuals and specific upper body exercises, so results may not generalise to all populations or exercises
Reference
Augustin, F., Piñero, A., Enes, A., Mohan, A.E., Sapuppo, M., Coleman, M., Wolf, M., Androulakis Korakakis, P., Swinton, P.A., Nippard, J.,Schoenfeld, B.J. (2024).Do cheaters prosper?Effect of externally supplied momentum during resistance training on measures of upper body muscle hypertrophy