Changes in your activity levels are one of the main reasons that losing weight after 40 may be more challenging than before. Like many women, you may be putting others first and simply not finding time to exercise. You may also notice that your joints can no longer handle the same activities as before. However, a lack of exercise can lead to muscle loss and fat gain.
People naturally lose muscle after 40, especially women after menopause. Because muscle burns more calories than fat, this can slow down your metabolism and make it harder to shake those stubborn pounds. Strength-training exercises -- lifting weights or doing body-weight exercises, like push-ups and squats -- at least twice a week can help you keep those muscles.