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5 Telltale Signs You Are Losing Muscle Mass & Don't Even Know It

Know the signs and what to do about muscle loss.

It's a sad fact of life that everyday things like losing weight and aging can cause you to lose lean muscle mass. As a matter of fact, according to Compass by WebMD, many individuals experience a 3% to 5% decrease in their supply of lean muscle every 10 years after turning 30. If you haven't noticed, listen up to learn the five telltale signs you are losing muscle mass and don't even know it. And next up, don't miss 5 Exercises Men Should Avoid To Regain Muscle, Expert Says.

Dieting, being sedentary, chronic diseases, and aging can all cause a decline in muscle mass.

woman on couch sedentary lifestyle concept

Mike Bohl, MD, MPH, ALM, the Director of Medical Content and Education at Ro, a certified personal trainer, and a member of our Medical Expert Board, tells Eat This, Not That!, "People often have a goal of losing weight, but this can come with a less-wanted side effect: losing muscle mass as well." Your body requires a specific energy level in order to function effectively each day. If you're on a diet and consuming fewer calories, your body is deprived of the energy it needs to run.

"[When dieting,] the hope is that your body then burns fat for excess energy—which is mostly what it does—but, to a lesser degree, your body burns protein as well (especially if you're on an extreme diet and your body is looking everywhere it can for an energy source)," says Dr. Bohl. "But dieting isn't the only time you may lose muscle mass. Certain chronic diseases can cause a loss of muscle mass, everybody naturally loses some muscle mass as they age, and even just living a sedentary lifestyle can lead to a decline in muscle mass."

If you're aware this may be happening, you can be proactive by taking the right measures to change things around and maintain your independence and ability to function. Keep reading for the signs you may be losing muscle.

1. You're losing weight too fast.

Dropping weight very fast is a sign you're losing muscle, too. Dr. Bohl warns, "This can seem like a good thing at first, if your goal is to lose weight and you see the numbers on the scale ticking down day by day. But it can also be a sign that you're working out too hard or that your dieting is too extreme and your body is malnourished, resulting in a loss of both fat and muscle."

Typically, losing one to two pounds each week is a healthy plan, or four to eight pounds each month. A faster rate than that can result in muscle loss.

2. You're not progressing, or your workout is getting harder.

Another indicator of muscle loss is that your fitness routine may feel more challenging, or your progress has stopped. Dr. Bohl suggests, "If you feel weaker, are having difficulty performing tasks you used to be able to do, or aren't seeing any improvement in strength at the gym over time, your muscles may need some more attention."

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3. You're more tired than normal.

man tired, fatigued during workout

If you are feeling more tired recently, it's a good sign you're losing muscle. Dr. Bohl says, "If you're feeling sluggish or low-energy, it may mean your body doesn't have enough nutrition, and it may resort to burning muscle."

4. You may look less muscular.

You may notice a difference in your appearance, but that can take time to actually see. Be mindful of how your clothes look, especially where you are typically more muscular. Dr. Bohl gives an example, saying, "If your sleeves are normally tight around your biceps or your shirt is normally tight across your chest but all of a sudden things are feeling looser, it might be muscle mass that you're losing and not just fat."

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5. You're dropping pounds, but your composition is the same.

Last but not least, if you're dropping weight, but your body composition is not changing, you're likely losing muscle as well as fat. Dr, Bohl points out, "There are several different ways to measure body composition, including with calipers or bioelectrical impedance analysis (which passes a weak electric current through the body). So if your weight is down but your body fat percentage is the same, it means fat isn't the only thing you've been losing. Tools for measuring body composition can be purchased (e.g., many modern scales now include bioelectrical impedance analysis) and are also often available for use at gyms."

Now that you know what causes you to lose muscle, let's discuss what you can do about it.

mature woman working out with resistance bands by the beach

When it comes to preventing the loss of lean muscle mass and gaining it back, it's important to know the cause. If you're on an aggressive diet that's causing you to lose muscle, it's time to reevaluate your plan. If your muscle loss is the result of a chronic condition, it's important to reach out to your physician to learn how best to achieve a body composition that's healthy.

If a sedentary lifestyle is causing a loss of muscle mass, it may be time to commence a workout regimen ASAP. Dr. Bohl recommends, "Even something small, like going on a walk every day, is a step in the right direction."

Once you've addressed the route of the muscle loss, it's time to redirect your efforts to strength training and protein intake. Dr. Bohl tells us, "It's simple, but working out your muscles is the best thing you can do for maintaining and growing them. You can do this with structured exercise—such as going to a gym and working out with machines, free weights, or bands—or unstructured exercise—like yard work and other manual tasks."

He shares that the amount of protein to consume each day t0 build and maintain muscle mass is between 1.4 to 2.0 grams per kilogram of body weight.

Alexa Mellardo
Alexa is the Mind + Body Deputy Editor of Eat This, Not That!, overseeing the M+B channel and delivering compelling fitness, wellness, and self-care topics to readers. Read more about Alexa
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