Muscles Shrink As We Age. Here's How to Fight Back.

Fight back against muscle shrinkage with our comprehensive guide. Explore proven techniques and tips to maintain strong and healthy muscles as we grow older.

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By Julia Reedy
Jovan Mijailovic
Edited by Jovan Mijailovic

Published June 5, 2024.

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Getting older is scary! With each birthday, we venture further into the ‘unknown’ that is older age -- further into the territory of “can my body still do this?” Our physical abilities change as we age; it’s natural, inevitable, and predictable. Our hormone levels shift, our bones get less dense, our dietary requirements recalibrate. But certain changes are (at least in part) avoidable. Muscle wasting is one of them; by making health-oriented choices, you can stay strong, even into your later years. Here’s how.

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What is sarcopenia?

Sarcopenia is the medical term for the loss of muscle mass and strength. And while you might associate this process with old age, sarcopenia can start as early as your 40s.1 Research about its cause is constantly ongoing, but studies show that its onset is multifactorial; it’s related to both involuntary causes like hormonal changes and neurological decline and lifestyle factors like insufficient exercise and poor nutrition.2

What all of these factors eventually boil down to is an imbalance in “cell turnover.” Cells in our body are constantly being destroyed and rebuilt -- a natural process that ensures our organs stay strong and function as expected. But if the “catabolic” (breakdown) arm of that process outweighs the “anabolic” (building) one, muscle loss sets in.

As you might expect, sarcopenia can ultimately limit an individual’s ability to move independently and can increase the risk of falling, disability, and overall frailty.2 It’s even associated with other chronic illnesses like arthritis and insulin resistance.2 Therefore, it’s essential that we get out in front of it and focus on preventing its onset in our younger years.

How to ward off (and even reverse) sarcopenia

Building muscle is essential if you’re worried about sarcopenia sneaking up on you in the future, or if you’re already starting to sense some effects.3 Here are the best ways to increase muscle mass and prevent or reverse sarcopenia’s onset.


In a surprise to no one, exercise is one of the best ways to build muscle. But you should know that different types yield different results. Most research shows that resistance training is your best bet, as it stimulates muscle growth and an anabolic state.4 Intensity, aka “load,” is perhaps the most important factor that connects strength exercise and muscle growth -- the heavier you lift, the more muscle you’ll build.4 When choosing a lifting plan, prioritize lower reps with higher weight rather than the converse, and perform multiple sets (3 is typical) of the same exercise or superset.

If you’re not one to hit the weight room, cardio work could be a great option for you. While cardio exercise isn’t necessarily known to build muscle, research shows it increases oxygen flow to your muscle cells, which might help increase the productivity of mitochondria (yes, the powerhouse of the cell) there. This can result in less cell death and disproportionate muscle breakdown.5 Try whatever mode you prefer -- 5 weekly sessions of running, hiking, or biking have all been shown effective.6 Even walking might do the trick; muscle growth was increased in men who followed a relatively easy treadmill interval routine.7


You might associate a protein-heavy diet with bodybuilders, and for good reason -- protein is absolutely essential for muscle growth. More specifically, the amino acid (a building block of protein) leucine is necessary for generating new muscle cells. Leucine-containing foods are largely animal products like dairy, eggs, and meat. You can also get it in whey, casein, and soy protein supplements. Protein consumption is especially important as we age -- research has shown that older adults need almost double the amount of protein than younger ones to achieve the same rate of “muscle protein synthesis.”8 It makes sense, then, that it’s recommended for older adults to consume 1.0-1.3g of protein per kilogram of body weight, while it’s typical for younger adults to need 0.8-0.6g/kg.9

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Vitamin D

Vitamin D has classically been connected to bone strength, but as nutrition research progresses, we’re seeing that it’s connected to much more in our bodies -- including muscle strength. While the exact mechanism isn’t quite clear yet, research showed that high vitamin D concentration in the blood (≥65 nmol/L if you’d like to take a peek at your InsideTracker chart) was associated with improved muscle function.10 To get levels like these, your best bet is probably vitamin D supplementation. Dosage is different for everyone, so use your InsideTracker recommendations to understand what’s best for you.

Finally, research shows that adequate omega-3 intake can also help to stimulate muscle growth. Studies on young, middle-aged, and elderly adults found that an omega-3 fatty acid supplement stimulated muscle protein concentration and synthesis in muscles.11,12 You can add omega-3s to your diet from a variety of sources, including fatty fish like salmon, mackerel, and sardines, seeds like flax and chia, and pasture-raised meat and eggs. Fish oil supplements may also be a good option for you, but consult a healthcare professional before adding anything to your regimen.

A healthy weight

As new research emerges, it’s becoming increasingly clear that sarcopenia is also independently associated with overweight and obesity. In fact, a 2011 study found that increased fat mass was associated with a decrease in muscle quality and a faster decline of lean muscle mass in both men and women.13 Use what you know about healthy exercise and eating habits to stay on top of your daily calorie balance.

How to measure your muscle function

As it stands, evaluating muscle function is the best method we have for tracking sarcopenia or any muscle-related changes. One of the best ways to keep track of your muscle function is to take a strength test every 4-6 months. Do your best to coordinate this with a personal trainer; a trained professional should administer it for you and take notes about your form, exertion, and the like. They’ll also help you calculate your “1-rep max,” a metric that will be most easily comparable test after test.

Choose a set of exercises that test a wide array of muscles and functionalities. Include both pulling (row) and pushing (bench press) movements, fast (hang clean) and slow (squat) motions, and concentric (bicep curl), eccentric (reverse pull up), and isometric (plank) contractions to get a complete picture of your muscular makeup.

Maintaining muscle strength as you age doesn’t have to be a chore. Make it a friendly competition with yourself! And keep the end goal in mind: a happy, healthy life at all ages.

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