PHOENIX (3TV/CBS 5) -- As we age, we know we lose bone density; it's called osteoporosis.
But did you know the same thing happens to our muscles?
It's called sarcopenia.
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Basically, the muscle is breaking down faster than we can rebuild it, and sadly, this starts happening at age 40.
Sherry Torkos is health expert who explained how this gets progressively worse as we get older.
"Up until age 40, there's a relative balance or equilibrium in its ability to build muscle and break down muscle. Once we hit 40, that slows down. Once we hit 50, we break down muscle at a much greater rate than we're able to rebuild it," she said. "So we lose about 1 to 3 percent of muscle mass each year after age 50, even if we're physically active. If we're inactive, you can lose up to 5 percent of muscle mass per year."
She said a lot of times people just forget about the important roll muscles play in our health.
Strong muscles help boost metabolism, regulate blood sugar and helps with our heart health.
Torkos said exercises that target big muscle groups are best.
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Things like lunges, squats, and push ups.
"For example, if you're doing bicep curls you're working your biceps, it's a great exercise but if you go down to the floor and do push ups you'll be working your biceps, triceps, shoulders and your chest. So for maybe five minutes of doing an exercise, you'll get more return on what you're doing," she explained.
Once you build that muscle, you need to feed it.
She recommends foods high in protein like meat or fish, but also nuts and even protein shakes when you're in a bind.
She said to look for the amino acid "lucein" which she said is best to really get those muscles going.