You don’t gain much without failure. There’s been little doubt of this when it comes to improving strength and muscle mass.

Chief among recommendations for lifting weights is to use high-intensity resistance above 60 percent of your one-repetition maximum—or the most weight you can lift in one effort—with failure defined as the inability to complete another full range of repetition (1).

But is failure really worth the effort?

The goal behind training to failure is greater muscle activation allowing for more muscle fibers to be used that would otherwise not be involved. Recruiting as many muscle fibers as possible is believed to result in maximal gains in muscle mass and strength on the trained muscles (2).

Although the logic behind failure seems sound, newer research suggests that the need for failure is not really clear-cut or absolutely necessary—and continual bouts of training to failure may even lead to an increased risk of injury.

Here’s what the limited number of studies suggest: Muscle activation and adaptations can differ greatly depending on training experience (3). For individuals new to strength training, training to failure is not essential for maximizing increases in muscle strength and mass (3). But for trained individuals, repetitions to failure might result in increased muscle activation, which could explain the slightly greater increases in muscle strength (3).

What remains unclear is if training to failure in trained individuals is necessary for increases in muscle mass. The current evidence shows slightly greater increases in muscle strength, but not muscle mass, after high-intensity weight training is performed to muscle failure compared to no failure (3).

Training to failure for a prolonged period may also result in overtraining (3). The higher risk of injury by repeated effort can cause overuse issues (4). Most guidelines recommend weight training to a level of substantial fatigue, ensuring strength and muscle mass increases, while avoiding failure (3). It’s a recommendation that’s especially important to populations that may have issues with going to failure, like the elderly and those with high blood pressure or chronic injuries.

The good news: Failure is not essential for maximal increases in strength and hypertrophy for these individuals (3). In fact, you raise the possibility of overtraining and injury when training to failure.

So the consensus is to use failure sparingly, if you’re experienced. But don’t use it at all if you’re inexperienced with lifting heavier weight. Keep in mind that results are not substantially better when using heavier weights anyway. Lighter weights will do. Far more important than reaching failure is proper form during resistance training using full range of motion.

References

  1. Drinkwater EJ et al. Training leading to repetition failure enhances bench press strength gains in elite junior athletes. J Strength Cond Res. 2005 May; 19(2):382-8.
  2. Wernbom M et al. The influence of frequency, intensity, volume and mode of strength training on whole muscle cross-sectional area in humans. Sports Med. 2007; 37(3):225-64.
  3. Nóbrega SR and Libardi CA. Is resistance training to muscular failure necessary? Front. Physiol. 2016; 7:10.
  4. Stone MH et al. Training to Muscular Failure: Is It Necessary? J Strength Cond Res. 1996 June; 18(3): 44-48. 1.     
  5. Mitchell CJ et al. Resistance exercise load does not determine training-mediated hypertrophic gains in young men. J Appl Physiol. 2012 Jul; 113(1):71-7.