Here’s the bad news: a couch potato lifestyle can mean losing up to 0.4 pounds of muscle per year once you reach age 50 (this loss can begin even earlier if you’re sedentary as a younger adult). However, even if you’re well over 50, you can increase your strength by 25 to 30 percent and add 2.42 pounds of lean muscle in an average of 18 to 20 weeks.
These statistics are from a report by University of Michigan researchers who reviewed the benefits of progressive resistance training for older adults. They suggest beginning with squats, modified push-ups and tai chi, Pilates or yoga. Then they advise working with a professional who can design a strength training program that advances to working with weights and machines to build and strengthen muscles. In five months, you could be much, much stronger.