“A key barrier to further understanding the influence of proximity-to-failure on muscle hypertrophy is that no consensus definition for set failure exists in the literarture.”
This is a problem because when different definitions are applied, we get different answers to the same question.
“For Hypertrophy, is it better to train close to failure or to complete failure?”
Since there’s no standard definition for “training to failure”, they defined Proximity-to-failure as the number of repetitions remaining in a set prior to momentary *concentric* muscular failure.
Also, since most of the literature reviewed didn’t have the same definition of “Set Failure”, they decided to look at Resistance Training performed through different velocity loss thresholds (and theoretically, the higher the velocity loss, the closer the Proximity-to-failure).
The results showed no evidence supporting that Resistance Training performed to momentary muscular failure is superior to non-failure Resistance Training. It was also shown that higher velocity loss thresholds, and thus, theoretically closer proximities-to-failure, elicit greater muscle hypertrophy in a non-linear manner.
“Conceptual non-linear relationship between proximitiy-to-failure and muscle hypertrophy. Our results suggest that closer proximities-to-failure are associated with muscle hypertrophy in a non-linear manner. Although the order of resistance training conditions displayed allows for visual inspection of a potential non-linear relationship between proximity-to-failure and muscle hypertrophy, the true proximities-to-failure achieved in each of these resistance training conditions are unclear and likely vary…”
Although these results suggest that training closer to failure is better than complete failure, it’s probably better to go with a mixture of both failure, and non (but close to) failure Sets based on 2 points:
1 ) The results of this Systematic Review should be taken with a grain of salt given that the definitions of failure in the literature is very ambiguous and the amount of studies on the topic is very scarce.
2 ) Many people don’t train neither to failure, nor close to, and if you’ve never taken a Set to Momentary Concentric Muscular Failure it’s unlikely you know how close you are to achieving it.
And although the results of this study should be taken with caution (training closer to failure is better than to complete failure), training, at least, close to failure is consistently shown to be superior than not doing so (PMID: 37523092, 28834797 & 37414459).
Main Reference:
