Breathing Technique

What It Is

A prescribed way of breathing through a working set, such as exhaling on the lift or holding the breath.

Why It Matters

Boddy grades training advice on the strength, power, and muscle it builds, and the evidence is very uncertain about whether how you breathe through a set changes any of them: no study has cleanly tested it, and the confident advice attached to breathing rests on a thin base. In healthy young women squatting at light and moderate loads, holding the breath through the lifting phase raised systolic blood pressure and the load on the heart against breathing through the same set, and made the effort feel harder.¹ In young untrained adults, a randomized crossover trial found that a moderate-load session raised a measure of arterial stiffness only when the last repetitions of each set were done with a breath-hold; with paced breathing it did not rise.² Both are single sessions, and nothing here follows anyone long enough to show that those swings matter.^1,2

Holding your breath is not simply a mistake. Bracing against a held breath is how lifters stiffen the trunk, and the pressures it generates inside the abdomen are highest in the squat and deadlift and lowest in the bench press.³ A brief hold appears to happen whether you intend it or not once an effort approaches maximal,⁴ and where the strain was measured at lighter loads the investigators read it as moderate but not dangerous, in the healthy young women they studied.¹ If you have or are at risk of cardiovascular disease, keep breathing through the set and treat it as a question for your doctor rather than a training one.

In the one trial that compared airways, breathing in and out through the nose, in through the nose and out through the mouth, or entirely through the mouth showed no difference in repetitions to failure, perceived effort, or blood oxygen in either sex, with only a small heart-rate difference among the men.⁵ So use whichever airway moves air comfortably, and if you brace, let the breath go between repetitions rather than carrying one hold across the set: no study has compared the two, but it keeps each hold brief. What no study supports is a breathing technique that builds more strength or muscle, which is why this sits here rather than as advice under Strength Training. Give your attention to load, volume, and progression, where the evidence does tie training choices to the strength and muscle you build.

• 1 Hummelmann, S. et al. (2026). Breathing technique-dependent acute cardiopulmonary responses during squats in healthy females. Physiological Reports. doi.org/10.14814/phy2.70831
• 2 Perry, B.G. et al. (2026). Resistance exercise with combined Valsalva manoeuvre acutely increases carotid-femoral pulse wave velocity in healthy untrained individuals. European Journal of Applied Physiology. doi.org/10.1007/s00421-026-06167-z
• 3 Blazek, D. et al. (2019). Systematic review of intra-abdominal and intrathoracic pressures initiated by the Valsalva manoeuvre during high-intensity resistance exercises. Biology of Sport. doi.org/10.5114/biolsport.2019.88759
• 4 MacDougall, J.D. et al. (1992). Factors affecting blood pressure during heavy weight lifting and static contractions. Journal of Applied Physiology. doi.org/10.1152/jappl.1992.73.4.1590
• 5 Lörinczi, F. et al. (2024). Nose vs. mouth breathing- acute effect of different breathing regimens on muscular endurance. BMC Sports Science, Medicine and Rehabilitation. doi.org/10.1186/s13102-024-00840-6