A central bodybuilding debate revolves around training to mechanical failure (where form starts to break due to fatigue) for muscle growth. Proponents of training to failure argue it is necessary to stimulate hypertrophy, while others believe it can lead to overtraining and increase injury risk.
Dr. Layne Norton (Ph.D. in Nutritional Sciences) published a video on his YouTube channel dissecting a January 2024 study in the Journal of Sports Sciences investigating the muscle-building effects of training to momentary muscular failure versus training with repetitions in reserve (RIR). (1) Check out the video below:
This study involved 20 experienced weightlifters (minimum of three years of training, three sessions per week). Half of the subjects had previously competed in bodybuilding or powerlifting competitions.
The eight-week study involved two training groups. One group trained their legs to failure; the other stopped one to two reps shy of failure.
The results showed no significant difference in muscle growth between the two groups, suggesting training to failure is unnecessary for maximizing muscle growth. In fact, the study found that training to failure may even be counterproductive.
The group that trained to failure performed fewer total reps compared to the group that stopped one to two reps shy of failure. This is likely because training to failure can lead to more neuromuscular fatigue, which can hinder your performance on subsequent sets.
Norton highlights that training to mechanical failure can be acceptable, especially for lifters who enjoy pushing themselves to the limit. This approach negates the negative performance impact on the subsequent sets.
If you train to failure, leave it to your final set.
To maximize muscle growth, you are better off focusing on progressive overload, which involves gradually increasing the weight, reps, or sets over time while leaving one to two repetitions in reserve.
Key Takeaways:
- Training to failure is not necessary for muscle growth.
- Hitting mechanical failure often induces excessive neuromuscular fatigue, potentially hindering your performance on subsequent sets.
- Stopping one to two RIR can help get more high-quality sets with better movement patterns.
Training to mechanical failure is not the magic bullet for muscle growth that some people believe it to be. Stopping one to two reps shy of failure to promote hypertrophy ensures better movement mechanics and reduces injury risk.
References
- Refalo, M. C., Helms, E. R., Robinson, Z. P., Hamilton, D. L., & Fyfe, J. J. (2024). Similar muscle hypertrophy following eight weeks of resistance training to momentary muscular failure or with repetitions-in-reserve in resistance-trained individuals. Journal of sports sciences, 42(1), 85–101. https://doi.org/10.1080/02640414.2024.2321021
Featured image courtesy of Shutterstock/ME Image.
