Take a deep breath and pedal faster

Cyclists who are already in great shape may be able to go even faster with a new kind of training regimen -- one for their breathing.

University of Arizona physiology researchers conducted a four-week experiment with 20 competitive cyclists, including some triathletes, to test the effectiveness of endurance training on the muscles used to control breathing.

Half the cyclists underwent 20 sessions that included deep breathing while researchers monitored carbon dioxide levels in their lungs and supplemented it to keep them from fainting. Using a metronome to pace their breaths, the cyclists gradually increased the speed and depth of their breaths during the 30-minute sessions.

Six cyclists received 20 “sham training” sessions, each five minutes long, while four cyclists received no training.

Afterward, those in the endurance training group posted a 12% improvement in the endurance capacity of their breathing muscles. Nine of the 10 cyclists dropped their times in time trials from an average of 47.1 minutes before training to 44.9 minutes afterward; the others didn’t improve.

The study authors said no one knows precisely how respiratory muscle training enhances endurance, although they think it more efficiently rids the body of carbon dioxide and eliminates shortness of breath, said lead author Ralph F. Fregosi, a physiology professor. Whether more intense or extended training sessions would lead to greater improvements remains to be seen, the authors wrote. The research was released May 6 in the online journal BMC Physiology.