Ultra-runners are different from you and me. They run more. But a new study of these racers, who compete in events longer than marathons, joins other recent science in finding that they also tend to be older and have some different health concerns than most of us might expect, suggesting that some beliefs about how much activity the human body can manage, especially in middle age, may be too narrow.
In recent years, the health effects of increasing inactivity have received plenty of scientific and media scrutiny. But the potential health effects of relatively gargantuan levels of physical activity have received less attention, and much of the science that does exist focuses on the potential dangers of over-exercise for the heart. Few studies have examined the more general health implications ó the benefits as well as the risks ó of training for and running more miles in a day than many of us complete in a month.
Hoping to better understand what happens to an ultra-endurance athleteís body, researchers at Stanford University and the University of California, Davis recently contacted more than 1,200 experienced ultra-marathon runners and asked them probing and almost impolite questions about the past and current states of their bones, hearts, blood pressures, prostates, breasts, skin, lungs, moods, bowels, eyes, waistlines, livers and many other body parts and systems. They also asked about their race histories, times, training regimens and any recent injuries and illnesses.
Then they compared the ultra-runnersí aggregate answers with comparable health statistics for average, more sedentary adults, while also comparing the training and injury-related data with similar information about recreational runners, like myself, who are not running 50- or 100-mile races on the weekend.
The results, which were published last week in PLoS One, were telling. The ultra-runners had a low, although not non-existent, incidence of high blood pressure and irregular heartbeats, with about 7.5 per cent of the runners reporting one of those problems. But less than 1 per cent had been diagnosed with heart disease or had a past stroke, and few had experienced cancer, with basal cell skin carcinoma being the most common malignancy, occurring in 1.6 percent of the runners.
On a less salutary note, the runners did report a high incidence of breathing problems, with almost a third of the group telling researchers that they experienced either allergies or asthma, often after running. That finding, while worrying, makes sense, the researchers note,