NEW YORK (Reuters Health) - Adults whose asthma is not fully controlled by medication might gain some benefits from adding an exercise routine to their lives, a small study suggests.
While exercise can trigger asthma symptoms in some people, there is also evidence that physically active asthmatics tend to have better overall asthma control than their sedentary counterparts. But whether that signals a benefit of exercise, per se, has been unclear.
For the new study, Shilpa Dogra and colleagues at York University in Toronto, Canada, recruited 36 sedentary adults with asthma symptoms that were only partially controlled. Nearly all were on medication, including, in many cases, drugs taken regularly to prevent asthma attacks.
The researchers had 18 study participants go through three months of supervised exercise training, where they worked out aerobically three times per week — with activities like jogging, walking on a treadmill or pedaling on a stationary bike — and performed strengthening exercises once a week.
The exercisers then continued to work out on their own for another three months.
The rest of the study participants served as a control group, maintaining their usual lifestyle habits.
After the initial three months, Dogra’s team found, the exercise group improved its average score on a standard questionnaire gauging asthma-symptom control — a change that moved the group from the category of “relatively well-controlled” to “well-controlled.”
Similarly, the exercisers reported gains in a questionnaire on asthma-related quality of life — which measures, for example, how much a person’s symptoms limit his or her daily activities or affect emotional well-being.
The exercise group also maintained those gains over the three months of home workouts, whereas the control group’s scores remained largely unchanged during the study period.
Previous studies have suggested that exercise can improve asthma-related quality of life. But this is the first to show that it may also aid symptom control, Dogra told Reuters Health in an email.
“The take-home message from this study is that 30 minutes of aerobic exercise at a moderate to vigorous intensity on three days of the week can lead to significant improvements in asthma control,” Dogra said.
And while the study used a supervised program to ensure that participants were following a specific regimen, Dogra said that adults with asthma can generally perform similar moderate exercise on their own.
That said, however, she advised that sedentary people with asthma talk with their doctors before taking up an exercise routine.
In their study, Dogra and her colleagues found little evidence of harm from exercise. One person in the exercise group had an asthma attack that required hospitalization, but it did not occur during physical activity and seemed to be unrelated to the workout regimen.
Still, exercise can trigger asthma symptoms in some people, and it is always advisable for sedentary people with major health conditions to get a doctor’s OK before becoming active.
The study had a number of limitations, including its small size and a lack of objective measures of asthma control.
On the other hand, Dogra pointed out that there are well-established benefits of regular exercise — including weight control and a reduced risk of heart disease — that people with or without asthma stand to gain. In fact, she noted, adults with asthma have been shown to have higher-than-average rates of heart disease and obesity, underscoring the potential benefits of physical activity.
There is still a need for much more research into asthma and exercise, according to Dogra. Among the remaining questions, she said, are whether children with asthma can gain similar benefits from exercise, and whether there are “optimal” types of activities for aiding asthma control.
European Respiratory Journal, online June 7, 2010.