The study found it's best practice to train to muscular failure/very close to muscular failure with some sets, but you don’t need to train for failure on every set with each exercise. The research did not suggest that training to failure inhibited or was worse for muscle growth than training a few reps short of failure.
LIFT WEIGHTS TO FAILURE SUMMARY
- The study found that training to failure had no benefit for muscle growth compared to not training to fail.
- No difference in muscle growth when training with lighter or heavier weights when sets were taken close to failure.
- There are recommendation when you should train to failure
Bodybuilding research has proven the decade-old belief that training to complete muscular failure is best for muscle growth. Most of the latest research studies have found that when the volume is equal, no greater muscle growth occurs between groups (i.e., training to complete failure vs. stopping short of training to failure). Some suggest that training to muscular failure results in more repetitions (i.e., more volume), more muscular tension, and the recruitment of high threshold type II fibers.(1, 2)
One of the major limitations of previous research is that there need to be guidelines defining the meaning of training to failure. For example, some people will stop a set when fatigued but still can do several more repetitions. This can be defined as exercising to muscular failure in some studies, but this is not true muscular failure (i.e., momentary muscular failure is defined as when an individual cannot complete the concentric portion of the repetition thru a full range of motion).
STUDY EXAMINES IF TRAINING TO FAILURE FOR HYPERTROPHY IS EVIDENCE-BASED
A review of the literature Martin Refalo set out to review the existing literature and answer the following question regarding training to complete failure?
1.) Studies comparing exercise to complete failure versus not exercising to failure with no specific criteria defining training to failure.
2.) Studies comparing exercising to failure versus not training to complete failure with specific guidelines in which the researchers defined failure as training to concentric failure (i.e., momentary muscular failure).
3.) Studies comparing velocity loss thresholds.
The results of the literature were clear:
a.) there is no evidence to support that resistance training performed to momentary muscular failure is superior to non-failure resistance training,
b.) higher velocity loss thresholds (i.e., exercising closer to the failure) do not always result in greater muscle growth, however, training closer to failure resulted in muscle growth in a non-linear manner. Meaning that stopping a few reps short of failure (i.e., 3-4 reps) resulted in no greater increases in muscle growth than exercising one rep short of failure. There must be a minimum threshold of intensity that must be met for muscle growth. Performing sets with insufficient or too much fatigue can equally affect muscle growth; there must be a “sweet spot.” and
(c) no moderating effect of either volume load or relative load on muscle hypertrophy when resistance exercise was performed using any definition of set failure versus non-failure.
The researchers found no effect of either volume load or relative load on muscle hypertrophy when resistance exercise was performed to set failure (using any definition) versus non-failure; however, the research seemed to favor lower weight, higher repetition exercise to failure compared to heavier weight, lower rep training.