Wednesday Bubble: stress, abdominal fat and exercise

Posted by Liz on Mar 2, 2011 in exercise | 4 comments

This is a day to neither burst nor unburst bubbles, but rather, explore an interesting set of hypotheses that ran across my desk:

Stress boosts that unsightly bulge around our midsection as we age. And, high intensity, intermittent exercise might eliminate some of it.

It’s hard to stay away from the the battle of the middle age bulge. It’s there every time many of us look in the mirror. And as I’ve written time and again; in women, the accumulation of abdominal fat is the perfect storm, multifactorial in cause and affecting a majority despite diet and physical activity. The culprits? Experts believe that it may be related to changes in ovarian function, hormone and just generally aging. To add insult to injury, as estrogen production declines, the body starts to rely on secondary production sites, such as body fat and skin. Thus, fatty tissue starts function like an endocrine organ instead of simply a passive vessel for energy storage. The body also struggles to hold onto bone mass and may compensate for its loss by holding on to extra body fat longer.

Now it seems that there’s another culprit at play: stress.

Cortisol is a hormone that is secreted by the adrenal glands. Its primary role in the body is to regulate energy (by producing blood sugar or metabolizing carbohydrates, protein and fats) and mobilize it areas in the body where is it most needed; consequently, cortisol levels tend to peak in the early morning and then gradually decline throughout the day. Cortisol is also produced in reaction to prolonged periods of stress, during which time it produces protein that the body can convert to energy. However, it also increases the creation of fat that may be deposited in fat cells residing deeply in the abdominal area.

Aging is believed to create further imbalances and an increase in cortisol levels, especially at night.  Recent data have also shown that overall, women have higher cortisol levels than men, and that certain women, especially those with greater amounts of abdominal fat, may be reacting to a large disruption in release of cortisol that causes a greater than normal difference between morning and evening levels of the hormone. This disruption is believed to be related, at least in part, to exposure to prolonged physical and mental stress.

If you are anything like me, your adrenals are working overtime and stress is pretty much a given part of your life. And, those abdominal fat deposits that were for most of your life, kept at bay, are starting to show up in the most inopportune places.

Now for the good news:

According to a recent review in the Journal of Obesity, there is accumulating evidence that high-intensity, intermittent exercise ( e.g. 8 seconds of high intensity cycling to significantly boost aerobic capacity followed by 12 seconds of low intensity, over a 20 minute period) performed at least three times a week may effectively reduce abdominal fat and even fat that lies just below the skin. The most important thing is consistency; although most studies have only evaluated these type of exercise regimens for short time periods, it appears that better results are associated with regular programs that last at least 3 months or more, especially among people who have larger amounts abdominal fat. Less certain, however, is the role that age may play, and if imbalances in cortisol levels due to prolonged stress influence how well intermittent, high intensity activity impacts fat deposits.

Not only have I upped the ante in terms of how long I exercise daily (i.e. 6o minutes) but I have started to pay more attention to how I’m working out in terms of intensity levels. Next up is the addition of intermittent high intensity intervals. Regardless of whether it’s cycling, elliptical or running, I’m hopeful that I can combat some of the bulge that’s creeping up. If anything, my heart is going to thank me!

What about you? In addition to watching what goes into your mouth, what are you doing to combat stress and that rotunda around your midsection?