In the final miles of a long run or triathlon run, your leg muscles become very tired. But your hamstrings, quadriceps and calves are not the only muscles that become fatigued during a hard run. You will experience breathing fatigue, or fatigue of your breathing muscles. 

Your breathing muscles become challenged during triathlon and it’s these breathing muscles that fatigue first. In fact, it is breathing fatigue that will limit your performance.

Signals are sent from your breathing muscles to your nervous system, with instructions to redirect oxygen from the muscles of your legs to those of your diaphragm, to keep your breathing going. Therefore, during running, the reason your legs may begin to tire first is because your breathing muscles are ‘stealing’ oxygen away from them.

Anyone who is a triathlete will be fully aware that during each phase – swim, bike or run – they will be breathing hard. But few pause to consider that hard breathing requires intense work by the respiratory muscles, which are just as susceptible to fatigue as other muscles.

Some scientific evidence does suggest that respiratory muscle fatigue is a limiting factor when it comes to endurance sports performance. However, these muscles can be trained independently of the rest of your body.  

Naturally, our everyday breathing is too easy to have a conditioning effect on your breathing muscles, but when you inhale and/or exhale against a resistance with a POWERbreathe inspiratory muscle training (IMT) device, these muscles are challenged even more than they are when you swim, bike and run. As a result, they become stronger and more fatigue-resistant and therefore less limiting in your triathlon performance.

Inspiratory muscle training can benefit all the three disciplines of a triathlon.