Training close to failure is important for making gains, we know that. But how close do you really need to be to maximize muscle growth and how does that differ from when trying to maximize strength?
Overview
What did they test? The authors performed a very detailed analysis of the current literature to explore the dose-response relationship between proximity to failure and muscle gains.
What did they find? Muscle hypertrophy increases as you get closer to failure whereas strength does not.
What does it mean for you? Training at 0-2 repetitions in reserve is advisable to maximize adaptations when training for muscle growth. When training for strength, training extremely close, or to, failure will not result in greater strength gains, although terms and conditions apply.
What’s the Problem?
Training hard is essential for hypertrophy; we’ve gone over this on many of our previous REPS issues. Training somewhat close to failure seems to be non-negotiable if one wants to optimize their hypertrophy gains although some questions still remain unanswered as to how close one really needs to train. If you remember, we covered a study 1 on Issue 11 of REPS that looked at whether training to failure was necessary to maximize hypertrophy adaptations and found that training to failure was indeed not necessarily better than not training to failure, assuming that a close proximity to failure was achieved. However, the study we looked at, aside from looking only at proximity to failure and its effects on just hypertrophy, it also did not really look at specifying the proximity to failure required to maximize hypertrophy. It is also important to note that the definition of failure varies quite a bit in the literature, something that the previously reviewed study attempted to work around, but we’re still faced with a “categorical” view of failure versus non-failure in the majority of studies exploring the role of proximity to failure and muscular adaptations.
Additionally, understanding the effect that proximity to failure has for strength gains can have many implications for trainees of all levels. Training to failure comes with a great deal of fatigue and for some individuals who are mostly focusing on strength development, eg: athletes who perform strength training to improve sport performance, the additional fatigue generated by training close to failure may be be taking away more than it has to offer, especially farther away from failure can still allow for optimal strength increases.
The previous study we had looked at on the relationship between training to failure and hypertrophy had shown that “the relationship between training to failure and hypertrophy is not as linear as previously believed”, something that may be challenged by the paper that we will be reviewing. The paper is titled “Exploring the dose-response relationship between estimated resistance training proximity to failure, strength gain and muscle hypertrophy: a series of meta-regressions” and it was led by Zac Robinson of Data Driven Strength who also happens to be Layne’s current powerlifting Coach and has also been featured as a guest expert in a previous issue of REPS. The paper was recently published as a pre-print, meaning it has not gone through Journal-level peer review just yet, but that didn’t stop it from receiving a lot of attention from the community, which also came with some confusion around some of its findings.
Time to dive in this beast of a paper and see what the fuss is all about!
Purpose & Hypothesis
The paper aimed to investigate in-depth the effect of proximity to failure on strength and hypertrophy. The authors aimed to explore the dose-response relationship of training to failure and muscular adaptations by actually estimating the repetitions in reserve (RIR) from the currently available literature.
