Is There Such a Thing as Too Much Exercise?
April Daniels Hussar, SELF magazine
Turns out there really can be too much of a good thing -- in fact, a new study compares extreme exercise regimens to taking drugs!
The study, presented at the annual meeting of the American College of Sports Medicine (ACSM) and published Tuesday in the journal Mayo Clinic Proceedings, finds that excessive exercise, such as "chronic training for, and competing in, extreme endurance exercise such as marathons, iron man distance triathlons and very long distance bicycle races" may cause serious cardiovascular injury.
"Physical exercise, though not a drug, possesses many traits of a powerful pharmacologic agent. A routine of daily physical activity can be highly effective for prevention and treatment of many diseases, including coronary heart disease, hypertension, heart failure and obesity," says lead author James H. O'Keefe, M.D., of Saint Luke's Hospital of Kansas City, Mo., in a press release. "However, as with any pharmacologic agent, a safe upper dose limit potentially exists, beyond which the adverse effects of physical exercise, such as musculoskeletal trauma and cardiovascular stress, may outweigh its benefits."
Related: Shed Pounds Without Starving Yourself
Dr. O'Keefe's data suggest that extreme endurance training can cause temporary structural changes to the heart, which, he says, usually returns to normal within one week. However, for some individuals, months and years of repetitive injury of this type can lead to the development of scar tissue and a thickened heart, which then can lead to abnormal heart rhythms and coronary heart disease.
Catherine G.R. Jackson, Ph.D., Fellow of the American College of Sports Medicine (FACSM), and professor and former chair of kinesiology at California State University, Fresno, tells HealthySELF that she is not surprised by the results of the study. "It is an outstanding observation and verification of what many of us have known for many years," she says.
According to Jackson, the potential danger of extreme exercising is not limited to heart issues. "Injury rates, mostly musculoskeletal, rise if individuals exercise more than five days per week," she says. "There can also be a depression of the immune system with prolonged exercise accompanied by lack of rest and recovery. Viral and bacterial infections would then increase."
Related: Yoga Moves for Flat Abs
But keep in mind -- this doesn't mean you should stop exercising!
"It's important to recognize that there are numerous health-related benefits to regular and appropriate levels of aerobic physical activity," says Michael F. Bergeron, Ph.D., FACSM, Executive Director, National Institute for Athletic Health & Performance and National Youth Sports Health & Safety Institute and a professor at the Sanford School of Medicine of The University of South Dakota. Those benefits, he says, include improvement in your cardiorespiratory fitness, which lowers your risk of morbidity and mortality.
In fact, even if you're working out TWICE a day, you're still in the clear as long as you're not overdoing it. "The accumulation of exercise throughout the day is fine as long as it is not excessive and not accompanied by severe fatigue," says Jackson.
Bergeron concurs, adding that it's important to make sure you're recovering between workouts, getting proper nutrition and staying hydrated. And while you should certainly participate in that marathon you've signed up for, you want to train carefully.
Related: 20 Superfoods for Weight Loss
"There are many individuals who expect to train hard and fast over a very short period of time and do not gradually condition so that the body can adapt over time," Jackson says. She recommends working with an exercise physiologist to train safely.
Bergeron agrees that it's a bad idea to jump into a vigorous, too-fast training schedule if you're not physically prepared for it. "For those who over-train and reach a point of diminishing returns... it is time to back off, build in recovery periods, and vary training and activities throughout the year," he says.
When it comes down to it, Dr. O'Keefe says his study does not take away from the importance of getting ENOUGH exercise. "Physically active people are much healthier than their sedentary counterparts. Exercise is one of the most important things you need to do on a daily basis," he says in the press release. "But ... a lot of people do not understand that the lion's share of health benefits accrue at a relatively modest level. Extreme exercise is not really conducive to great cardiovascular health. Beyond 30-60 minutes per day, you reach a point of diminishing returns."
In other words, the main lesson from this study, according to Jackson, "Is that moderate exercise is beneficial and that those who do not participate in excessive exercise should not feel guilty."
More from SELF:
5 Simple Steps to Cellulite-Free Skin
3 CrossFit Total-Body Workouts
50 Healthiest Snacks
6 Secrets to Firing Up Your Metabolism