Fresh out of the lab, we have a new study comparing the effects of training with or without failure on trained participants.
18 trained men were assigned an 8-week program, consisting of 3 non-consecutive training days each week.
The subjects were placed into two groups: one group lifting until concentric muscle failure, and the other group NOT lifting to failure and holding a couple of reps in reserve.
Both groups performed 3 sets of 10 of each exercise.
Measures of muscle strength (1RM) and training load (10RM) were taken pre, peri (4W), and post (8W) and the total training volume (TTV), ratings of perceived exertion (RPE), and the estimate of repetitions to failure were also established.
The study found that 1RM and 10RM increased in both groups with no difference between them, but the training to failure group reported higher perceived exertion (RPE).
Consistent with the current literature on training to failure, it seems that training to max or very close to it is equally effective for increasing muscle strength and training load, however training to failure leads to far greater perceived exertion and fatigue accumulation.
My preference and recommendation is to always leave a couple of reps in reserve rather than taking sets to all-out.
For all the extra grunt and grind that there doesn’t appear to be an added benefit to white-knuckling your workouts but you will gather a lot more fatigue overall.
Which, in my experience leads to slower progress across a longer training cycle.
Resistance Training with Repetition to Failure or Not on Muscle Strength and Perceptual Responses. Vieira, et al. 2019