Breathing Training for Runners and Triathletes: A Practical Guide

Late in a long run or the run leg of a triathlon, it rarely feels like your lungs are “full.” It feels like breathing itself has become hard work. That is not in your head: your breathing muscles are working near their limit, and that work has a cost.

What Happens to Breathing on Long Efforts

As intensity rises, you move far more air per minute than at rest, first by breathing deeper, then mostly by breathing faster. The diaphragm and the muscles between your ribs do that work for the whole session. In well-trained athletes working hard for long periods, these muscles can fatigue.

Studies from the University of Wisconsin showed that when the work of breathing is very high during maximal exercise, blood flow to the legs drops, and when that work is reduced, leg blood flow improves. In other words, your breathing muscles and your legs compete for the same supply.

What the Research Says About Breathing Training

A 2012 systematic review and meta-analysis in Sports Medicine pooled 46 studies of respiratory muscle training in healthy people. Its main findings are useful for planning:

• Respiratory muscle training improved endurance performance overall.
• Less-fit athletes tended to gain more than highly trained ones, though trained athletes still improved in many studies.
• Benefits were larger in longer events.
• Both main types of training, strength-style and endurance-style, worked about equally well.

It is not a replacement for running, riding and swimming. Think of it as a small, targeted addition, like strength work for your breathing.

Sport-by-Sport Tips

Running

Many runners naturally settle into a rhythm, such as breathing in for a few steps and out for a few. You don’t need to force a pattern, but a relaxed, steady rhythm on easy runs can help you stay calm and efficient. On hills and in races, let the rhythm speed up rather than fighting it.

Cycling

An aggressive aero position compresses your abdomen and makes deep breathing harder. If your breathing feels restricted, check your fit, and practice breathing into your sides and back while in position on easy rides.

Swimming

In the water you can only breathe when your stroke allows it, so a strong, complete exhale under water matters. Exhale steadily through your nose and mouth while your face is in, so your short inhale can be a full one.

Fitting It Into Your Week

• A short respiratory muscle training set once or twice a day, about five minutes in total
• Easy sessions in the right heart-rate zones, with relaxed, low breathing
• One or two harder sessions where you practice staying in control of your breathing
• A lighter breathing-training week before key races

Know Your Starting Point

A breath-by-breath test shows how your breathing rate and volume respond to rising effort, where your fuel use shifts and what your training zones should be. If breathing is what limits you, you will see it in the data. Start with Respiratory Muscle Training: How to Get Started.

Sources

• Illi SK, Held U, Frank I, Spengler CM. Effect of respiratory muscle training on exercise performance in healthy individuals: a systematic review and meta-analysis. Sports Medicine. 2012;42(8):707–724. Read the abstract
• Harms CA, et al. Respiratory muscle work compromises leg blood flow during maximal exercise. Journal of Applied Physiology. 1997;82(5):1573–1583. Read the study

This article is for general education and is not medical advice. Talk to your physician before starting a new exercise program or testing.