You probably have heard that muscle weighs more than fat. Many people notice a small weight gain when they begin lifting weights consistently. As a general rule, if you lift weights 2 to 3 times a week, you can gain 1 pound of muscle per month for about 6 months. After that, the rate of increase slows down as you start to reach your genetic potential. For the same reason, you will make a lot of progress on weight progression at the beginning, but the longer you lift; your progression will lessen because you are reaching your genetic potential.
Don’t be alarmed at the extra pounds of weight from weight training because it is well worth the effort. For every 3 pounds of muscle you build, research shows you increase your resting metabolic rate by about 7 percent. For example, if your body burns 1,200 calories per day (not counting exercise or any other movement), you would burn an extra 84 calories per day with those 3 extra pounds of muscle.
Many women have a difficult time outgrowing 2-3 pound dumbbell weights, because they are afraid that if they increase the weight they will bulk up. If you are happy with the strength and appearance of your muscles, you can do a maintenance program with 5 pound weights. However, if you want more strength, you could progress to 8 or 10 pound weights and still not bulk up. Using heavier weights can increase muscle size, but it’s highly unlikely that you’ll get bulky. Women don’t naturally have enough of the hormone, testosterone, required to build huge muscles, and even if you could bulk up, you’d have to use significantly heavier weights.
Another option to tone muscle is to increase your repetitions instead of increasing weight. A high-repetition/light-weight program will develop muscle tone and increase strength and endurance without significantly increasing muscle size.