Heavy Meals, Vigorous Exercise Linked to Heart Attack and Stroke
Franklin and colleagues collaborated with Bally's Total Fitness health clubs to determine just how often people die during or just after working out, and who's most likely to do so. "When you walk into one of these clubs, your membership card is swiped. That provides a record of the number of visits for each member," he says. They analyzed the records at 320 clubs, where "between 1997 and 1998, there were approximately 182 million visits made by 3 million members."
In all, 61 men and 10 women had died at the clubs; the victims were an average of 53 years old. "That translates to one death out of every 2.57 million workouts," Franklin says. "This study indicates that among the general population, at least among members of commercial fitness facilities, the risk is extremely low."
When they looked more closely at precisely who had died and why, they found that "a third had a history of cardiovascular disease or known risk factors." Half had exercised less than once, and three-quarters less than twice per week in the months prior to dying. In fact, only three had been regular exercisers who hit the gym five times each week. "More than half of the people who died were engaged in some sort of aerobic exercise -- probably extremely vigorous -- when they died," Franklin says.
But, he says, "this does not mean that aerobic exercise is dangerous. The public needs to increase the regularity of their workouts to get benefits and reduce their risk of a cardiovascular event." If you simply can't find a way to bump up your frequency, he says, "don't go in there and turn the treadmill up to 8 mph. Sporadic exercisers should adopt a mild to moderate pace."
In another study, Gerald Fletcher, MD, and colleagues found that this kind of regular exercise -- five sessions per week -- can even help men who've already had a heart attack or undergone surgery to treat blocked arteries. "After 6 months, we saw a significant increase in HDL -- the good cholesterol -- regardless of workout intensity," he says, and there's no reason to believe the findings would be any different in women.
Fletcher, who is a cardiologist and professor of medicine at the Mayo Clinic in Jacksonville, Fla., believes in practicing what he preaches. He runs about 14 miles per week, on the beach or the road, at a rate of 10-12 minutes per mile.
"Overall, if you look at all the factors, the fact is that physically active people have half the risk of coronary artery disease as their sedentary counterparts," Franklin says. "The main message is that the benefit of exercise far outweighs the risk." He himself walks about 12 miles a week with his wife and dog, usually in one-hour stints, and also does some resistance training (such as lifting weights) twice a week.