Heart specialists have found positive results in ramped up rehab workouts for their patients, a group previously restricted to low-intensity, low-stress exercise.
Similar to high-intensity interval training in elite athletes, the short bouts of action at 85% to 95% of maximum heart rate improves oxygen uptake and use, according to the research at the Mayo Clinic in Rochester, Minn., and Norwegian University of Science and Technology.
Ray Squires, program director of cardiovascular health and rehabilitation at the Mayo Clinic, has been using high-intensity intervals in patients for about four years.
"There's been a natural progression over time of what we've thought exercise for patients with cardiovascular disease should be," Squires told the Wall Street Journal. "If you go back 50 years, people were told to hardly do any exercise for weeks after a heart attack. Gradually we learned that was wrong."
While top endurance athletes will push themselves near maximum heart rate for minutes or miles, the rehabbing patients will work at the top aerobic level for just 20 seconds, then continue at a more moderate pace.
The practice has not been fully accepted, according to the Wall Street Journal piece.
The American Heart Association doesn't have a position on high-intensity interval training for rehab. Barry Franklin, an AHA spokesman, says that although recent research is encouraging, larger randomized, controlled studies are needed in higher-risk groups.
"I'm still not convinced ... that taking people with coronary disease and exercising them at 95% of their [maximum] heart rate is a safe procedure," says Dr. Franklin, who is director of the cardiac-rehabilitation program and exercise laboratories at the William Beaumont Hospital in Royal Oak, Mich. Dr. Franklin says he currently uses intense bursts of exercise only in selected lower-risk patients, in the later, maintenance phase of rehab.