Don't Let Your Workouts Slow You Down!

Regular exercise, outside of our normal daily physical activities, is a vital part of maintaining a healthy lifestyle and a healthy body weight. The 2008 Physical Activity Guidelines for Americans recommends that we should exercise more than 300 minutes per week of moderate-intensity exercise or more than 150 minutes per week of vigorous-intensity exercise, though less than half of us meet these recommendations.

Research studies have suggested that committing to a regular, structured exercise program might cause us to reduce the amount of physical activity we get during the rest of the day, partially compensating for our daily workout.  Whether our choice of exercise intensity impacts our overall daily amounts of physical activity remains unclear and is the subject of a new obesity research study. 

For this new study (free to download), research investigators enrolled 36 overweight or obese postmenopausal women who had been inactive during the 6 months before the study started.  Eighteen of the women were assigned to moderate-intensity exercise and the other 18 women were assigned to vigorous-intensity exercise such that calories burned were similar in both groups of women.  Total physical activity (structured exercise + normal daily activities) was measured both on days with structured exercise and on days without structured exercise.  The results of this investigation were very interesting.

Moderate-Intensity Exercise.  In women exercising at a moderate intensity, the amount of energy burned was higher on days when they exercised (~577 Calories) than on days when they did not exercise (~450 Calories).  However, this difference between exercise and non-exercise days (~127 Calories) was substantially less than the calories burned on the treadmill, suggesting that the women burned less calories outside of their workout on days that they exercised.

Vigorous-Intensity Exercise.  In women exercising at a vigorous intensity, the amount of total energy burned was LESS on days with treadmill exercise (~450 Calories) than on days without treadmill exercise (~520 Calories), suggesting that the women in this study were reducing the amount of physical activity they did outside of the structured program on days they exercised.

These are fascinating results that suggest we might automatically compensate for any structured exercise program to which we commit if we are not careful.  According to this study, the greatest risk appears to come with vigorous-intensity exercise.  In this group of women, those that committed to vigorous-intensity exercise on average reduced their non-treadmill physical activity so much that they burned more calories on non-exercise days than they did on exercise days.  While this reduction in non-treadmill physical activity was seen in both groups of women, it was clearly more pronounced in women following a vigorous-intensity program.  These findings make it clear that we need to educate individuals deciding to start a structured exercise program about the importance of maintaining their normal levels of physical activity in addition to their exercise program in order to achieve the best possible results.

Walking 30-45 minutes per day is a great way to start a healthy exercise and weight loss plan.  Visit us at www.drtabor.com to learn more about my easy diet plan and physical activity plan.