A study of triathletes published in the online edition and October issue of Radiology reveals that the heart adapts to triathlon training by working more efficiently.
"To our knowledge, this is the first study using MRI to investigate effects of triathlon training on cardiac adaptations," said lead researcher Michael M. Lell, M.D., associate professor at the University of Erlangen-Nuremberg in Erlangen, Germany.
Dr. Lell and colleagues conducted cardiac MRI on 26 professional male triathletes (mean age 27.9) and 27 male controls (mean age 27.3), who were recreationally active no more than three hours per week. Triathletes in the study were top national and international competitors with six or more years of continuous training.
The cardiac MR images revealed that, compared to the recreational athletes, the triathletes had larger left atria and larger right and left ventricles. The triathletes' left and right ventricles also had greater muscle mass and wall thickness.
"In competitive athletes, it is important to distinguish physiological adaptations as a result of training from pathological conditions such as cardiomyopathy, the most common cause of sudden cardiac death," Dr. Lell said.