Does Strength Training Cause Weight Gain?

Push yourself with those dumbbells to maintain a healthy weight.
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Strength training increases your muscle mass and metabolism, which tends to lower your body fat and ultimately your jeans size. If you are overweight, you are likely to lose weight slowly, and if you are underweight, you may gain some weight. Strength training provides a valuable way to regulate your weight at a healthy level. You may not need to worry about what the scales say; measure your progress by the fit figure looking back at you in the mirror.


    Because muscle weighs more than fat, “you may not notice any immediate loss of total body weight,” notes James L. Hesson, an exercise science professor. If you are already at your optimum body weight, hoisting weights reduces your proportion of body fat helping you achieve a healthier, toned body. Unless you plan to be a female Olympic weightlifter, you are probably just like 99 percent of women who cannot develop bulky muscles without spending hours upon hours in the gym.

Weight Control

    Even if you gain weight, your increase in muscle will allow you to maintain a healthy weight more effectively than through dieting alone. The higher metabolic rate of muscle -- which unlike fat consumes calories even while you are at rest -- can boost your metabolic rate by up to 15 percent, the Centers for Disease Control and Prevention notes. This helps with weight loss and maintenance.

The Scale Can Lie

    Say you’ve become convinced of the benefits of strength training two or three times a week for 20 minutes or more and have a range of exercises designed to challenge your big muscles -- especially the glutes and quads -- to burn fat. But your scales may indicate that nothing has changed despite your hard work. Without an assessment of your body composition, “this favorable change could go unnoticed and lead to frustration on the part of the exerciser,” writes Irene Lewis-McCormick, a trainer and fitness writer, in “A Woman's Guide to Muscle and Strength.”

    Get a handle on your fat loss -- rather than your seemingly static weight -- by switching to your scales’ body-fat measuring feature, which is available on most bathroom scales that you can buy. Your gym likely has a higher-end model, which a trainer or assistant can use to measure your body fat. Or you can measure reductions in the inch counts of your arms, chest, waist, hips, thighs and calves, which is an alternative way to measure fat loss.

The Skinny on Weight

    If you are a bit too thin -- 2 percent of American women, especially those aged 20 to 39 actually qualify as underweight -- and want to increase your functional strength for everyday tasks, you’ll need to tweak your diet as well as maintain your strength training to gain weight. Add 250 to 700 additional daily calories, depending on your current weight while keeping up a solid strength program, which should enable you to gain lean mass at a rate of about 1 pound every 10 days.

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