Contributed by Dr. David Geier, The American Orthopaedic Society for Sports Medicine (AOSSM)
Do you want to lose weight, but despite long sessions on the treadmill or elliptical trainer?
Most adults seem to fall into that category. Studies have shown that few Americans obtain at least 150 minutes of moderate to vigorous physical activity recommended in the Physical Activity Guidelines for Americans. Fortunately a new study published in the American Journal of Health Promotion suggests that any physical activity – assuming it is fairly intense – can help people lose weight, even if only done for very short periods.
Intensity and duration of physical activity
Jessie X. Fan and others at the University of Utah compiled data on 2,202 women and 2,309 men aged 18 to 64 who completed the National Health and Nutrition Examination Survey. They grouped the physical activity of the subjects into four categories: higher-intensity sessions greater than 10 minutes, higher-intensity sessions less than 10 minutes, lower-intensity sessions greater than 10 minutes, and lower-intensity sessions less than 10 minutes.
Higher-intensity exercise was defined as greater than 2,020 counts per minute as measured by an accelerometer. Researchers pointed out that walking 3 miles per hour was equivalent to that level of intensity. However, all activities – like walking in a store, climbing stairs, and much more – counted as long as it met the intensity levels monitored by the accelerometer.
What matters more? Exercise duration or intensity?
The authors found that high-intensity exercise, whether performed in sessions greater than 10 minutes or in shorter ones, was associated with a lower risk of obesity.
“What we learned is that for preventing weight gain, the intensity of the activity matters more than duration,” Dr. Fan, Professor of Family And Consumer Studies and Associate Dean of the College of Social Behavioral Science at the University of Utah, explained in a press release about the study.
Better yet, every minute counts – literally. For every minute of high-intensity activity women performed each day, their odds of obesity dropped 5%. For men, that one minute per day of high-intensity activity lowered the odds of obesity 2%.
The authors explained it in another way. For every additional daily minute of short-duration high-intensity activity, the body mass index of women dropped 0.07. Translated into calories, one minute per day equaled 0.41 pounds.
“Knowing that even short bouts of ‘brisk’ activity can add up to a positive effect is an encouraging message for promoting better health,” Fan concluded.
Recommendations
I’m not going to tell you that longer sessions of exercise aren’t important. They clearly have tremendous impact on improving not only physical health, but also mental and emotional wellbeing. For losing weight, though, short bursts of activity might be helpful.
• I have previously recommended parking at the back of parking lots and walking extra distance into stores for work. Stick with that – but walk that distance a little faster.
• Don’t just choose the stairs over the elevator. Climb the stairs a little more quickly.
• If you’re playing with your kids in the pool, play games where you swim across the pool – and swim a little harder doing it.
Every activity – no matter how short – matters.