09/07/2011 07:54 am ET | Updated Nov 01, 2011

The Key To Lasting Weight Loss

While recently assessing a frustrated new client, I heard a complaint that I've heard over and over again. "I've been walking five days a week for 40 minutes, and while I initially lost some weight, I can't seem to get any more pounds off! What am I doing wrong?"

It's not what you're doing wrong, it's what you're not doing. Most people associate cardiovascular activity with weight loss, but few recognize the missing component --strength training. In addition to cardiovascular exercise, building and maintaining lean mass (muscle) is crucial for weight control, and here's why.

As we age, our bodies naturally begin a process called "sarcopenia"-- the process of losing muscle. We lose approximately a half pound of muscle annually, and we can replace that with about two and a half pounds of fat per year. Add that up over a period of five or 10 years, and guess what? You're living in a body that you don't recognize anymore! Nor do you like it! Regular strength training helps to reverse this process, as well as improving quality of life by increasing overall functional strength for daily activities, and it can help prevent and treat osteoporosis as well. Oh yes, I forgot to'll look better, too! Your body will look leaner and more toned and you'll take up less space in your clothes because muscle takes up less space pound for pound than fat. Not a bad deal.

Why does muscle affect weight? It's simple. Muscle is metabolically active tissue, which means that it boosts your metabolism to burn more calories -- 24 hours a day, not just when you're exercising. I like to think of muscles as little furnaces, melting the fat away! So the more muscle you have, the more calories your body is burning throughout the entire day -- even when you're at rest.

So how can you send those fat pounds packing? Here's what the American College of Sports Medicine suggests: for those of you with extra weight who actually need to take the pounds off, moderate weight loss can be achieved with 150-250 (or more) minutes of activity per week. Obviously, the more you put in, the more significant the weight loss. On the other hand, if you and your scale are on good terms and you want to keep it that way, you can maintain your optimal weight by engaging in 150 or more minutes per week of moderate intensity cardio exercise. In addition to that, strength training is recommended two or three times per week. I always remind my clients that it is important to rest muscle groups after strength training for at least one day before engaging in the next strength workout. This "recovery" period is as important as the workout itself. This is when the muscle fibers that are broken down during training have a chance to rebuild themselves--and they will gradually rebuild to be stronger. Note to you overachievers: working muscles more often than two or three days per week may not not get you better results. In this case, "more" is not necessarily "better".

In addition to contributing to weight loss and control, there are several more strength training benefits that should be noted. They are:

-Increased muscle-to-fat ratio, which may lower the risk of heart disease
-May relieve arthritic symptoms
-May decrease depression
-May reduce risk of muscular and skeletal injuries due to improvement of balance

Basically, the importance of strength training cannot be ignored. So if you're frustrated like my new client because you're knocking yourself out with hours and hours of cardiovascular exercise and can't seem to lose weight, try strength training. There is much to be gained...and many pounds to be lost!

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