09/19/2013 11:33 am ET Updated Nov 19, 2013

Why Weight Gain After Menopause?

A complaint I hear on a regular basis in my practice amongst menopausal and post-menopausal women is a problem of "unexplained" weight gain. In actuality, there are combinations of physiological factors that do indeed easily explain this dreaded phenomenon. The good news is that we are not stuck with this problem. In fact, with some effort and commitment, we can impact the situation through exercise.

A major factor contributing to weight gain after menopause is the cessation of menstrual periods. Throughout your reproductive years, for two weeks before a period, your body burns an extra 200 to 300 calories per day in preparation for menstruation. That's a lot of free calorie burn -- without having to do any extra physical activity! Once those periods stop, you no longer get that "freebie" for two weeks every month. So after menopause sets in, you have to find other ways to burn those calories in order to maintain your weight. If you suspect I'm suggesting more exercise -- you're right!

Then there's the issue of decreasing estrogen production. According to WebMD, "In animal studies, estrogen appears to help regulate body weight... and reduced estrogen may also lower metabolic rate" -- which means fewer calories overall are burned. The article goes on to say that it is believed that the same thing happens to women after menopause. A 2012 Medscape article discussed a study by Spangenburg, Wohlers and Valencia in which similar findings were supported. That study goes on to say that "loss of estrogen function leads to insulin resistance [which results in increased fat storage and difficulty losing weight], visceral adiposity, hepatic dysfunction and striated muscle dysfunction." All of this sounds pretty ominous, I know, but here's the good news. The study determined that every one of these problems can be prevented or reversed by increasing the amount of exercise a woman gets on a regular basis. Good news indeed.

Other factors affecting weight gain due to menopause are the loss of muscle mass and the decline of aerobic capacity. Losing muscle, or "sarcopenia," is a naturally occurring process that is significant in weight control because muscle is the stuff that burns fat. The more you have, the more calories you burn throughout the 24-hour day. But just because it's a natural process doesn't mean that you can't intervene. Strength training will impact this problem, as well as improving overall functional strength and improving bone density -- another casualty of menopause.

Finally, the rate at which you're able to use up energy during exercise is called "aerobic capacity." As we age, we may need to increase the amount of time and intensity in our exercise regime in order to use the same energy and control body weight. If this seems overwhelming, refer to my article on interval training for ideas on how to manage exercise intensity.

To sum up, menopause is a naturally occurring physiological process that we don't need to fear. We do have the power to impact the symptoms so as to live a healthy life, and exercise -- cardiovascular, strength training, and flexibility training -- once again comes to the rescue. So if you haven't begun an exercise program yet, menopause is yet one more incentive to begin now and enjoy the endless benefits that exercise has to offer.

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