Researched Nutrition for the Soul by Rania Mekary, PhD.

Here is a treat. Straight from the castles of Harvard University is a message from Dr. Rania Mekary. Rania and I go back to our early, late, and current days at Fitcorp, now Bodyscapes, in the Longwood Medical Area of Boston, MA. Rania teaches cardio kickboxing, Group Power, and is certified in spinning:

Derek asked me to write a paragraph about nutrition and physical activity (PA).  Since I am a researcher at the Harvard School of Public Health and I spent 7-8 years doing research on physical activity and weight gain among other topics, I decided to share with you some of my published findings.  You might know it all already but it is good to back it up with scientific evidence.

In a recently published study by Mekary et al., 2009, we prospectively examined the association between physical activity patterns and weight gain prevention among premenopausal women in the Nurses’ Health Study II, and found that sustained discretionary physical activity for at least 30 minutes/day, particularly is if more intense, is associated with a reduction in long-term weight gain, and greater duration is associated with less weight gain.  Sedentary women of any baseline weight who increase their physical activity by even 11-20 minutes/day will benefit; but overweight women will benefit the most.  Moreover, sedentary behavior independently predicted weight gain. 

Important findings to highlight in this study are that:

1) PA intensity did matter as brisk walking predicted less weight gain than non-brisk walking, for the same time spent.

2) There was a dose-response relationship between duration of PA and less weight gain, and even an 11-20 min/day increase was beneficial.

3) Overweight and obese women appeared to benefit the most.

4) Decreased TV viewing was independently associated with reduced weight gain.

In another study on PA and weight loss maintenance,

In another paper by Mekary et al., 2010, we prospectively examined the association between physical activity patterns and long-term maintenance of intentional weight loss among premenopausal women in the Nurses’ Health Study II who had previously lost >5% of their body weight.  Here are our findings:

Whereas weight loss may be achievable, keeping the lost weight off can be very challenging over the years. We have shown that physical activity (PA) is highly associated with weight loss maintenance. Several factors come into play of this association: PA duration and type; baseline body mass index; and baseline PA. There was a significant dose response relationship between increased PA duration and intensity and weight regain. A 30 min/day increase in jogging/running was more protective than the same increase in brisk walking, which was more protective than the same increase in slow walking. The benefits of activity are greater among overweight/obese than normal weight women. Sustaining 30+ min/day of discretionary PA was associated with less weight regain; however, among sedentary women who want to prevent weight regain, their PA increase had to exceed 30 min/day to be beneficial. Decreasing TV viewing time was also associated with decreased weight regain.

Among sedentary women, PA increase had to exceed 30 min/d to be beneficial and a significant dose-response relationship was evident.

Also, from another study I published on the same topic by Mekary at al., 2009 on time replacement, we found that Substituting 30 min of jogging/running for 30 min of slow walking has twice the effect on less weight regain as compared to substituting 30 min of brisk walking  for 30 min of slow walking.

In a large 16-year prospective cohort study of premenopausal women in the Nurses’ Health Study II on bicycling and weight control published by Mekary et al., 2010, we found the following:

1)    In this study, we found that overweight and obese women controlled their weight better than normal weight women if they increased their bicycling time.  This was similar to our previous findings on physical activity in general and weight gain prevention (Mekary et al, 2009,IJO) or weight loss maintenance (Mekary et al., 2010, Obesity).
 2) We also found even "small steps" can make a difference for women who did not bicycle and then started to bicycle over the years, i.e. an increase of as little as 5 min/day lessened the weight gain over the years.
 3) Finally, our study showed that "the more bicycling, the less weight gain" as there was a clear inverse dose response relationship between increased bicycling and weight gain.

People tend to focus more on how to lose weight.  However, it is crucial to understand how to prevent further weight gain that is inevitable with increased age, whether it was prevention of weight regain after having lost weight, or just maintaining the current body weight.  Eventually, when people manage to control their current body weight by performing the right amount and type of physical activity, the more time they invest in performing that physical activity type, the more the energy balance will become negative and they end up burning calories more than what they are ingesting, which will eventually lead to weight loss, if weight loss was the goal.  But again, once has to know how to avoid regaining the lost weight.  And this is what I have published in one of my papers.

Another thing I would like to add is that physical activity type is very crucial.  It is very important to perform some type of resistance exercises in order to maintain the muscle mass and increase metabolic rate.  In fact, we are about to submit a paper on weight training and change in waist circumference in men as compared to other types of moderate to vigorous aerobic activities.  Do you want to take a guess on which physical activity type leads to the most favorable changes in waist circumference?   I will let Derek know once our paper is published and he will share it with you.

Happy holidays to you all and may you have a wonderful blessed, happy, and healthy New year 2014.

Rania

With heart,

Derek

Derek Arledge, CSCS         www.teempt.com          TEEM Performance Training