"Certainly the higher workload that you place on your heart, if it's not as well-trained as it should be, can be a bit more risky for cardiac events or sudden death," says the study's lead author, Dr. Sanita Atwal, a physician with the Canadian Armed Forces.
Atwal, who was at Dalhousie University in Halifax, Nova Scotia, during the study, looked at 113 men, aged 35 and older, during recreational games from January through March of 2000 in Sydney, Nova Scotia. She and her colleagues measured the players' heart rates by having them wear portable monitoring devices before, during and after at least one game.What they found was that all 113 men had heart rates well above the "recommended exercise target rate for cardiac fitness," which is 55 percent to 85 percent of a person's maximum heart rate.
In fact, most of the players spent 30 minutes above 85 percent of their maximum heart rate, the study says. It also found that 70 percent of the men had a slower-than-normal heart rate recovery time after they finished a game.
"We found that everybody was above 85 percent of their maximum heart rate, and they were all actually clustered around the 100-percent mark. We had a mean of about 104 percent. So, everybody was exercising at really high heart rates," Atwal says.
Maximum heart rate is calculated by subtracting your age from 220. For example, if you're 40, your maximum heart rate should be 180 beats per minute.
None of the players experienced any serious heart problems during the course of the study. However, such elevated heart rates could increase the possibility of heart attack or other cardiac problems, Atwal says.
Atwal admits the risk of death for adult recreational hockey players is minor; she estimates it at about one in 1.5 million.
To put that in real numbers, an estimated 500,000 Canadian men aged 35 and older play recreational hockey. If they each play 30 games a season, that's 10 heart-related deaths per season, she says.
"So it's quite a small risk. We really don't want to scare anybody off hockey," Atwal says.
She hopes her findings will encourage weekend hockey players to get more regular physical activity to ensure their hearts can handle the strenuous demands of the game. Atwal suggests a moderate cardiac workout -- brisk walking, jogging, cycling, swimming -- at least three times a week.
If you're one of those weekend hockey players, Atwal says you also should control potential cardiac risk factors. Don't smoke, and beware of high cholesterol, hypertension and diabetes. It probably wouldn't hurt to lose those extra pounds around the middle, either, she says.
Make sure you warm up before your game, and have a proper cool down after the game to minimize stress on your heart, Atwal says. Also, be aware of your exercise target heart rate and try to adhere to it.
Dr. Murray Mittleman, a heart expert at Harvard Medical School, says Atwal's study is useful, but he doesn't want anyone to come away with the misguided notion that intense exercise is bad for you.
"It's important that this not come out as something against a form of exercise that could be very beneficial," he says. "In fact, if more people are out there playing hockey, along with other forms of exercise, it's a great way to help lower your risk of having a heart attack at any time."
There's nothing wrong with hockey or any other kind of vigorous exercise, as long as you supplement it with a regular exercise program, he says.
"What we know about exercise is that a little bit is good, but that more is better," Mittleman says.
Atwal's study appears in the current issue of the Canadian Medical Association Journal.