Moving day can be hectic, but it also marks a new beginning. Today’s move brings us closer to downtown Kelowna, British Columbia, to a really nice spot. While settling into the new apartment, I’ve been catching up on some reading, including a fascinating article in this month’s MASS about training to failure. This topic has always intrigued me, as it has significant implications for training programming.
Training to failure refers to performing an exercise until you can no longer complete another repetition with proper form. The debate centers around whether pushing to failure is beneficial or detrimental to overall progress. One argument suggests that training to failure early in a workout leads to excessive fatigue, limiting the total volume achievable. For example, if you aim for three sets of eight to ten reps on the bench press at 225 pounds and hit failure on the first set of ten, subsequent sets will likely yield fewer reps due to accumulated fatigue. This could result in a total of 22 reps (10 + 7 + 5) compared to potentially 25 reps (9 + 8 + 8) if you had reserved some energy on the first set.
The opposing viewpoint posits that reaching failure is essential for activating a full spectrum of motor units, including the larger, higher-threshold muscle fibers. Proponents argue that without reaching failure, you might miss out on potential muscle growth. This debate exists within the scientific community, and researchers continue to investigate the optimal approach.
A 2017 study explored this question by examining three different training protocols with ten trained young men, each having an average of eight years of training experience. A crossover design was employed, meaning each participant experienced all three protocols with four-week washout periods in between. The protocols consisted of high-volume training to failure, high-volume training not to failure, and low-volume training not to failure.
The high-volume to failure group performed three sets of ten reps to failure on the Smith machine bench press and squat. The high-volume not to failure group followed the same protocol but only performed five reps with their ten-rep max for each set, effectively leaving five reps in reserve. To match volume, this group completed six sets of each exercise. Finally, the low-volume not to failure group performed three sets of five reps with their ten-rep max.
The study measured various parameters at different time points: before training, immediately after, and at 6, 24, 48, and 72 hours post-training. These measurements included counter-movement jump height, mean propulsive velocity on the Smith machine exercises, and blood markers like creatine kinase for muscle damage, along with growth hormone, testosterone, and cortisol levels.
The results revealed minimal differences between the high-volume and low-volume not to failure groups, with the only significant difference being higher growth hormone levels in the high-volume group immediately post-training. However, notable distinctions emerged between the failure and non-failure groups. The non-failure groups experienced only a temporary impairment in counter-movement jump height immediately after training. In contrast, the failure group exhibited impairments in counter-movement jump, squat performance for 24 hours, and bench press performance for 48 hours. Creatine kinase levels also returned to baseline within 24 hours for the non-failure groups, while the failure group took 48 hours.
This study provides compelling evidence that, even with matched volume, training to failure results in significantly greater fatigue and performance impairments compared to not training to failure. This aligns with a 2016 meta-analysis cited in the MASS article, which found no significant differences in strength and hypertrophy gains between training to failure and not training to failure, regardless of exercise type or training experience.
These findings suggest that training to failure should be used more strategically. While it can be beneficial to push limits occasionally, consistently training to failure may not be necessary for optimal results. The article recommends reserving failure training for isolation exercises and performing it only on the last set of the last exercise for a given body part. Another suggestion is to periodize failure training, incorporating blocks of high-intensity training to failure interspersed with periods of higher volume training with fewer sets to failure.
