Pump You Up

Did you hear about woolly mice? Scientists recently created hairy mice using genetic modifications based on traits from woolly mammoths. I’m not sure how useful this is, but the mice are very cute.

Science is amazing- I’m a big fan! (I better be, I married a scientist ) Things are constantly being learned about our amazing, complex world.  It’s also ever-changing as we learn more information. Sometimes new information contradicts old, or at least changes our understanding of it with more nuance. And that’s great….we don’t know what we don’t know (hello interstitium) until we learn it. We’re getting smarter!

Take, for example, GLP-1 and GLP-1/GIP drugs such as Ozempic or Mounjaro. They are “once in a generation” wonder drugs for treating type 2 diabetes and obesity. They work by mimicking a natural hormone called GLP-1, which helps regulate blood sugar levels and appetite. However, an important aspect of using this medication is the potential for muscle loss. 

A paper recently shared with me about GLP-1 medications showed a loss of muscle mass, as much as 25% to 39% of the total weight lost over 36–72 weeks, though amounts vary in studies. Losing weight at the expense of lean muscle can lead to future problems, including reduced basal metabolic rate, decreased strength, fitness, balance, and tone, reduced bone density, and an increased risk of weight recurrence. So it’s essential to prioritize muscle preservation.

Muscle mass loss as we age, called sarcopenia, is natural, as is some loss of muscle mass while losing weight. However, GLP-1 use can cause a more rapid loss of skeletal muscle than normal. This is especially true for anyone who is more sedentary, has a poor diet, osteoporosis, or chronic kidney disease, or is older. Conversely, the benefits of using GLP-1s for weight management can outweigh the risks for individuals with obesity or type 2 diabetes. Since we are born with basically all the muscle fibers we will ever have (yes, you read that correctly, you are born with a certain number and proportion of muscle fibers, primarily determined by genetics, but training and other factors can influence their size and function), it’s important we maintain our fibers for as long as we can. Although new pharmacological treatments are being researched, the current key is to balance weight loss with strategies that preserve muscle mass to maintain overall health and metabolic function.

The first recommendation is to increase your protein. It’s important to note that this loss of muscle mass and metabolism is a result of rapid weight loss and is not caused by the drug itself. Having a reduced appetite from taking GLP-1s can lead to insufficient calorie and protein intake, causing a loss of muscle mass. So choosing which foods to eat when you are hungry is important. Foods high in protein help you feel fuller, longer and lead to less lean mass loss.

More and more is coming out about getting enough protein in our diets. So much so that it can be hard to get the recommended amount, especially the right kind. Jayne shared this article about the symptoms of not eating enough protein. How much protein is the right amount? That’s a discussion best had with your doctor, and it’s important to note that a high-protein diet is not for everyone. I’ve seen recommendations of 25-30 grams per meal, at least 60-90 grams per day, and 0.5-0.9 grams per pound you want to weigh per day (for a goal weight of 150 pounds, that’s 75-135 grams of protein a day). Regardless of how you measure it, it’s more than the RDA, (which is the minimum amount of protein necessary to prevent muscle loss), and it’s probably more than you’re eating. The “right” protein is lean protein like lean meats, legumes, fish, tofu, and whole grains.

• To raise your protein levels quickly, try adding at least one protein source to every meal and snack. For example:
  • Add nut butter to apple slices and sprinkle the slices with hemp seeds
  • Swap your morning bowl of cereal for a higher-protein option like scrambled eggs with spinach or Greek yogurt topped with seeds and berries
  • Buy fish or lean cuts of meat and serve them with lots of dark green and colorful veggies.
  • Top your salad with chicken, fish, hard-boiled eggs, or beans

The second important recommendation is to exercise regularly, specifically strength and resistance training. Some GLP-1 users may experience fatigue or reduced physical activity, which can further contribute to muscle loss. If you’re losing weight without even needing to work out, you may feel less inclined to prioritize exercise, despite its many other benefits beyond weight loss. Don’t!

Endurance and resistance or weight training effectively slow down muscle loss accompanying weight loss. Resistance training can also increase muscle strength and improve physical function. Beverly Tchang, MD, an assistant professor of Clinical Medicine at Weill Cornell Medicine, says “people who are at risk of frailty or sarcopenia (e.g., elderly) and taking a GLP-1 should be more mindful of incorporating resistance training to mitigate lean mass loss.” 

While we incorporate resistance training at the PIH studio, many types of resistance exercises can also be performed at home using weights, resistance bands, or even bodyweight exercises, such as squats and wall push-ups that do not require equipment. Evidence suggests one set of 10 to 15 repetitions for eight to 10 exercises twice a week, progressing to three sets of eight to 10 repetitions three times a week, will build muscle mass with time and consistency. Exercise snacks are also a great way to improve strength and functional ability by performing resistance training at lower intensities (short bursts) but at higher frequencies (more often) throughout your day and week.

Neither of these recommendations is really new or earth-shattering, just not as easy as taking a pill (or a shot). But they are proven for good health. Individuals who rapidly lose a large amount of weight commonly regain most of the weight in the subsequent 5 years. When GLP-1 medications are discontinued, healthy behaviors are essential for long-term weight maintenance. The key to healthy, sustainable weight loss is maintaining protein intake and nutrition, performing regular resistance exercise, and staying consistent. Together, they improve mobility, quality of daily life, and increase both your lifespan and healthspan.