Training to failure: do you need it to build muscle?
What the meta-analyses say, and how to set the intensity of your sets day to day.
Muscle failure is the point where you cannot do a single extra rep with good form. For some lifters, it is the only way to "really" train. For others, it is a source of pointless fatigue. Research settles most of the debate.
What the research says
In 2022, Jozo Grgic and Brad Schoenfeld pooled 15 studies comparing sets taken to failure with sets stopped short. The result: no significant difference, either for strength or for muscle growth. Training to failure does not seem necessary, but it does not seem harmful either.
Another meta-analysis, published in 2023 by Martin Refalo and colleagues, reached a similar conclusion: no evidence that momentary muscle failure beats sets that stop a little earlier for muscle growth. The authors point to a non-linear relationship: getting close to failure helps, but going all the way adds little.
There is one notable exception: with light loads, 60% of your max or less, muscle growth can match what heavy loads produce, as long as sets are pushed very close to failure. With a light weight, it is the end of the set that does the work.
Practical guidelines
- Aim to finish most sets 1 to 3 reps short of failure: the last rep should feel genuinely hard.
- On big compound lifts (squat, deadlift, bench press), stay a bit further from failure: fatigue is higher and a missed rep can be risky.
- On isolation exercises and machines, taking the last set to failure is easier and safer.
- If you hit failure on your first set, the following ones suffer: you lose reps, and therefore volume.
To keep your sets consistent from one to the next, also make sure to respect your rest time.
The indicator that does not lie: your numbers
Stopping "two reps short of failure" takes some honesty. The most reliable way to know whether your sets are hard enough is to look at your numbers: if your weights and reps climb over the weeks, the intensity is right. If they stall, something needs to change.
How Loaden helps
- Every set is logged in one tap, with its weight and reps, so your history stays reliable.
- Loaden suggests the weight for your next session based on your performance, so you apply progressive overload without doing the math.
- When an exercise stalls for several sessions in a row, the app detects it and suggests what to change.
Sources
- Grgic J. et al., "Effects of resistance training performed to repetition failure or non-failure on muscular strength and hypertrophy: A systematic review and meta-analysis", Journal of Sport and Health Science, 2022.
- Refalo M.C. et al., "Influence of Resistance Training Proximity-to-Failure on Skeletal Muscle Hypertrophy: A Systematic Review with Meta-analysis", Sports Medicine, 2023.
- Schoenfeld B.J. et al., "Strength and Hypertrophy Adaptations Between Low- vs. High-Load Resistance Training: A Systematic Review and Meta-analysis", Journal of Strength and Conditioning Research, 2017.
Numbers instead of guesswork
Loaden tracks your weights set after set and tells you when you are stalling.
