Physical Activity Requirements for Maintaining Body Weight

We are all aware of the importance of physical activity as part of a healthy lifestyle.  Getting regular exercise can help with weight loss, building muscle, supporting healthy bones and more.  The numerous benefits of exercise have been explained in good detail by places like WebMD and the Mayo Clinic.  However, the amount of exercise for which we all need to strive isn't always as clear and might vary based on our goals. 

In regards to obesity and preventing weight gain, recommendations for exercise tend to vary from about 150 minutes per week to about 420 minutes per week (60 minutes per day).  A new research study in the Journal of the American Medical Association examined the relationship between 3 different amounts of physical activity (less than 150 minutes per week, 150 - less than 420 minutes per week, and at least 420 minutes per week) and body weight changes over time.  This study was done in over 34,000 women with an average age of 54 years and consuming a usual diet.  The results of this study showed:

• Over an average of 3 years follow-up, all three groups of women gained weight over time, but weight gain was less in the group exercising at least 60 minutes per day.
• Women exercising less than 150 minutes per week were 11% more likely to gain 5 lbs over the 3 year follow-up, while women exercising between 150-420 minutes per week were 7% more likely to gain weight.
• Body mass index (BMI) effected this relationship between exercise and weight gain prevention such that only women with a normal BMI (< 25) were able to prevent weight gain with higher levels of physical activity.
• Among women who successfully maintained their weight over the long term, the average amount of physical activity was 420 minutes per week (60 minutes per day).

These are interesting results that might impact future guidelines for physical activity in regards to maintaining a healthy body weight.  Based on this study, women who are at a healthy body weight will need to participate in moderate-intensity physical activity for at least 60 minutes per day in order to maintain their body weight over time.  Interestingly, this level of physical activity had no benefit in regards to weight maintenance in women who were overweight at the beginning of the study or who were over 65 years of age.  It is important to remember that this study was done in women following their normal dietary habits, so it might be necessary for some women to not only increase their physical activity, but also to modify their eating habits to prevent further weight gain over time.  The lead author discusses this study in the JAMA video below.



Finding your right combination of healthy eating and physical activity is an important part of developing a healthy lifestyle.  My easy diet plan is a great place to start!