Exercise can stoke metabolism

Can you really do anything about your metabolism?

The answer: yes and no.

I often hear people blame their metabolism for gaining weight, and the marketers know it. I hear schemes -- and see products that people waste money on -- on how to make your body burn more calories by avoiding the practical, proven and free.

Some of those plans and products involve drinking ice-cold water, eating hot pepper and consuming an array of new energy drinks, one of which purports to "Burn up to 100 calories and more in each can!*" and "Raises metabolism over a 3-hour period.*" Yeah, notice the asterisks saying, "Individual results may vary" and that the Food and Drug Administration has not evaluated the statements.

Doctor weighs in

Questions about "my slow metabolism" is a subject that comes up often at physician-assisted "medical weight-loss centers," such as Medi-Weightloss Clinic in Mount Pleasant. So I called the clinic's Dr. Thomas Egan, a board-certified cardiologist who, after 20 years of practicing in Massachusetts, wanted to shift his professional focus from fixing heart disease to preventing it.

Egan says metabolism is only a major weight gain issue for those with hypothyroidism. He adds, "The thyroid is the master setting point."

Otherwise, good health and fitness is more of a function of serious and sustained lifestyle change: eating healthy proteins, vegetables and low glycemic, fiber-rich carbs, and healthy fats along with regular, vigorous exercise.

Egan not only talks the talk, he walks the walk.

The 5-8 doc has been active all his life and maintained a lean, 150-pound body by lifting weights and doing sports that involves bursts of running, such as basketball and tennis, rather than long-distance running (he just doesn't like it).

Lifting weights in a proper way, he says, is key to keeping the metabolism fire burning hot because it not only strengthens muscle, but also stimulates natural growth hormones and testosterone (which women have, too, and that's not a bad thing), which builds and maintains muscle and bone.

Egan stresses that effective weight training for weight loss and maintenance is not demonstrated by the hulks that lift super heavy weights and sit on benches five minutes between sets. Rather it's vigorous and varied.

"I've always done everything as fast as I can," says Egan. "I like to get my heart rate up and keep it up."

Revving that engine

The human body and the car often are compared. But in modern life, we want our bodies to burn fuel and our cars to burn as little as possible. One way to burn the fuel is to rev the engine -- often.

Unless you are a cyclist in the Tour de France or running a marathon, most of your calories burned during the day are not directly related to exercise. Instead, it's the amount burned just to maintain your body functions at rest, aka "resting metabolic rate," says Egan.

Generally, the Mayo Clinic estimates that the average person burns 60 percent to 75 percent of his calories just living, not exercising. That's why, increasingly, studies show that eating healthy food is a greater priority than exercise, though both are important.

But exercise, particularly vigorous exercise, is important to burn more of that extra percentage and to reap the benefits of what physiologists call "excess post-exercise oxygen consumption," or EPOC. In a nutshell, it's the increase in the resting metabolic rate after exercise.

There's been some controversy about EPOC, but generally, studies and most experts support it.

"After vigorous exercise, we've seen caloric expenditure increase for up to 48 hours," says exercise physiologist Tom R. Thomas, Ph.D., director of the exercise physiology program at the University of Missouri in Columbia, on the school's website. "The longer and harder you work out, the greater the post-workout metabolism increase and the longer it lasts."

Subjects in Thomas' research burned 600-700 calories during one hour of running at about 80 percent of their maximum heart rate. During the next 48 hours, they burned about 15 percent more calories -- 90-105 calories extra --than they otherwise would have. About 75 percent of the post-workout metabolism increase occurs in the first one to two hours after exercise, according to Thomas.

Stoking the fire

So how do you keep your body revving to burn as many calories at rest as possible?

Research seems to point to more intermittent sessions than fewer, longer ones. In other words, two intense 30-minute sessions per day rather than one less intense, 60-minute session.

The key may be exercising more times,

Several studies have concluded that intermittent aerobic exercise bouts elicit a greater EPOC response when compared with continuous exercise bouts.

Among the studies was one done in 1997 at the University of South Australia. Researchers investigated the effects of a continuous run of 30 minutes at 70 percent of VO2 max (oxygen consumption) versus an interval run that included 20 bouts of one-minute duration at 105 percent of VO2 max, or "supramaximal exercise." The authors reported a significantly greater EPOC following the intermittent bouts of supramaximal exercise.

Some studies also point to the importance of resistance training to EPOC responses.

In a 2001 study at Ohio University, researchers showed a circuit resistance training program using heavy weights, short rest periods and lasting only 31 minutes was able to generate an EPOC that persisted for 48 hours. Results showed that metabolism was increased 21 percent in the first 24 hours after a session and even 19 percent in 48 hours after.

The researchers point out that for a typical 180-pound individual it equated to 773 calories expended post exercise.

In all that I've read, and heard, and lived, this points to an ideal formula of aspiring to two 30-minute sessions of vigorous exercise, ideally one for strength and one for cardio.

Pepper in taking the stairs instead of the elevator, going on a walk at lunch time or maybe even throwing in a set of random push-ups and you can stoke that metabolism even more.

Now how's that for a scheme to lose weight and get fit?

No charge.

Reach David Quick at 937-5516 or dquick@postandcourier.com. See his Running Charleston blog at www.postandcourier.com/blogs/running_blog.

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