If you push yourself with a good, intense resistance-training program, your muscles will respond. Not only will the pounds start dropping, but you’ll completely change your body shape for the better. You’ll lose fat thighs, flabby arms, and soft bellies. Your skin will appear firmer too, and your bones and ligaments will become stronger.

The more lean muscle you have on your body, the more your metabolism rises. It is estimated that one pound of muscle requires fifty to a hundred calories per day to function. Increasing your lean muscle by as little as three to five pounds can have a profound effect on your daily caloric burn by raising your basal metabolic rate (BMR), which is the number of calories you expend while sitting or sleeping. So if you add three to five pounds of muscle to your body, your BMR will increase by 250 to 500 calories per day. If you maintain or decrease your caloric intake, that equivalent to one to three pounds of weight loss per week.

Great trainers know the importance of muscle. Many of us are able to eat whatever we want—not because of exceptional genetics, but because of muscle. So the more muscle, the more allowances in food you can eventually give yourself, or at least your battle to get thin will be much easier.

I’d like to emphasize that starting a workout program is not an excuse to pig out. Why would you spend hours burning off calories just to pile them back on? The goal is to be calorie-deficient each week, and exercising makes that happen. If you’re eating like a pig on workout days or rewarding yourself with too much food after every workout, you’ll be breaking even and not seeing strong results. If you burned five hundred calories during your workout, for example, then allow yourself a splurge or help yourself to second helpings at dinner every time, you’re wasting time and effort. When I feel tempted to overeat, I think to myself: Eating this cake means I have to triple my cardio tomorrow. That usually does the trick, because I hate cardio! Don’t blow your workouts with bad snacks.

Resistance training also changes the hormonal environment in your body—for the better. Two for the major fat-burning hormones, testosterone and growth hormone—which assist in building muscle and eliminating fat—skyrocket during your exercise sessions. Afterward, DHEA kicks in. DHEA is an amazing hormone, responsible for fat burning, muscle building, mood, sex drive, and immunity. Supplies dwindle with age, so do everything you can to keep levels high, including exercise.

Want to feel less stress and more balance?

In addition, exercise flushes out stress hormones from your body and elevates levels of feel-good endorphins. Endorphins are emotional tranquilizers that reduce stress and anxiety. When these brain chemicals are turned on consistently and in high doses, they addict you to working out. After a proper workout, you should feel a high that lasts throughout your day and affects all your personal connections with people. I am walking proof of someone who needs an endorphin high and relies on it to get through life. Exercise is a powerful cure to a sometimes sick and stressful environment. Do it right and you’ll learn to crave exercise as much as you used to crave junk food. So along with diet, exercise is ideal for keeping your hormones and chemistry in balance.