· You’ll burn more calories in the long term and increase your metabolism. It takes more energy for your body to maintain muscle cells than it does fat cells. So by lifting weights you’ll increase your muscle mass, which in turn will boost your metabolism and the end result will be turning your body into a fat-burning machine. · Women between the ages of 30 and 70 lose an average of 22% of their total muscle. But worse than that, over time, once that muscle ha