Wrinkles, worsening vision, and hair loss aren’t the only things caused by aging. Unfortunately, an undeniable sign of aging is also loss of muscle mass (sarcopenia). For every 10 years you don’t exercise and strength train, you’ll lose about 5-7 pounds of muscle. And less muscle mass means a slower metabolism and less efficient use of energy, which means it’ll be harder to lose weight and keep it off. Is that worth leading a sedentary lifestyle and not exercising?

Fortunately, no matter how old you are and how ummm…lazy you’ve been, it’s never too late to exercise. Whether you’re 25 or 65, if you commit to regular exercise and resistance training, your body will respond positively as long as your regimen is suitable for you (in other words, it should be challenging but not so much so that injury may result). You’ll increase muscle mass, boost your metabolism and lose fat. Studies have even shown that people in their latter years can redevelop muscle mass from strength training and increasing protein consumption.

But before you hit the gym or start any exercise program, speak to your doctor. You need to make sure your body can handle exercise, especially if you have an existing medical condition. A certified personal trainer can also help you determine a suitable plan.