No matter how dedicated you are to your exercise regimen, at some point, you’re likely going to take a break from it. You might embark on a month-long trip across the country during which you prioritize experiencing national parks — not the inside of a CrossFit gym. You may develop a health condition that requires you to relax on the couch for a few weeks. Or, you might simply want to give your body and mind a rest from the perspiration and grind — and that’s perfectly fine.
Even if you’re satisfied with your workout-free hiatus, you may still be curious about how much time it takes before you start losing the muscle you’ve built up over the years — and how long it’ll take you to regain it all if that’s something you desire. That’s why Shape consulted with an expert exercise physiologist to answer “how long does it take to lose muscle?” and offer some insights on how you can slow down the process. Rest assured, your well-toned biceps and powerful legs aren’t hopeless.
What It Means to ‘Lose’ Muscle
To address the question of “how long does it take to lose muscle?”, it’s crucial to define what it entails to “lose muscle” in the first place. Most frequently, the “muscle” people are referring to is either muscle size or muscle strength — which aren’t completely correlated, according to Alyssa Olenick, Ph.D., C.I.S.S.N, C.F.L.1, an expert exercise physiologist and sports nutritionist. “Generally, when individuals gain more muscle, they will gain more size and they will be able to move more weight and become stronger,” she explains.
However, your neuromuscular system also plays a role in determining your muscle strength: as it adapts to training, the motor neurons that connect with muscle tissue become more capable of contracting the muscles, generating a force that moves the weight you’re lifting, she elaborates. “So becoming stronger is partly about developing and recovering muscle tissue, but it also involves the ability to recruit that muscle tissue to produce greater force,” Olenick states.
How Long Does It Take to Lose Muscle?
If you skip the gym during a week-long trip, don’t worry about it. Typically, it takes approximately two to three weeks to observe significant decreases in muscle strength, according to Olenick. “If you were to take a vacation for a week and a half and you didn’t engage in any lifting, you might notice a slight decline when you return, but not a substantial one,” she adds. “Your maximum weight capacity probably won’t decrease by much.”
Likewise, you might start to experience a reduction in muscle size after taking a week or two off from your usual workout routine, says Olenick.
It won’t initially be caused by a decrease in actual muscle mass, but instead a decrease in carbohydrates and fluid,” she remarks. In case you didn’t know, your body stores carbohydrates, which can later be converted into energy during physical activity, in your liver and muscles. Furthermore, these carbohydrates bring hydration into the muscles along with them,” she clarifies. “When you first cease weightlifting, the majority of the ‘bulk’ that appears to be lost is due to this reduction in carbohydrates and water in your muscles, whereas actual muscle loss can begin within a few days and progresses at a slower pace,” states Olenick. “The primary reason for losing carbohydrates and fluids initially is because your body utilizes them for energy and metabolism, resulting in the shrinkage of these stores.
How to Prevent Muscle Atrophy
Having said that, the phrase “utilize it or forfeit it” applies when it comes to preserving muscle mass and strength. If you’re completely inactive during this period (think: you’re confined to bed or have an injury that hinders movement), your strength and muscle size may decline more rapidly than if you’re staying moderately active (e.g. going for strolls, performing a few bodyweight exercises at home, dancing around the house), says Olenick. This muscle loss may be attributed to a decrease in muscle protein synthesis — the process in which your body employs amino acids to repair muscle damage caused by exercise, according to research published in the journal Current Opinion in Clinical Nutrition & Metabolic Care. If the breakdown of muscle protein exceeds its synthesis (which again, occurs post-workout), muscle loss can transpire, according to an article published in the International Journal of Sport Nutrition and Exercise Metabolism. “However, if you’re still generally active and moving, it won’t be as much [of a decrease], and that muscle will bounce back faster than it took to acquire it initially,” adds Olenick.
Nevertheless, if you used to be a regular weightlifter and have recently switched to exclusively cardiovascular workouts, you may still observe some muscle loss, says Olenick. “While any activity can help preserve muscle, cardio is a form of exercise that is catabolic or ‘breaks down’ tissue to assist in generating energy for fuel,” she explains. “[Nevertheless,] the process would be slower than if someone was fully inactive.” Her recommendation for runners? Attempt to complete one to three full-body strength workouts per week, and remember to consume sufficient protein and carbohydrates to support the activity. “Those things will also aid their running performance as well,” she adds.
How to Gauge Muscle Loss
If you’re seeking an estimation of how much strength you may have lost after taking a well-deserved break, your best option is to reference your rating of perceived exertion (RPE), says Olenick. This tool is a measure of the intensity of your workout or physical activity based on how strenuous you perceive your body to be working. So if squatting with 20-pound dumbbells or performing 15 push-ups feels more arduous than it did before your break, that’s an indication you may have experienced some strength loss, she explains.
Assessing physical muscle loss is a bit more methodical; you’ll need to undergo a body composition assessment, such as by utilizing an InBody machine that measures muscle mass, body fat, and total body water content, says Olenick. While you can use a measuring tape to determine if you lost muscle size in the biceps or thighs, for example, that technique doesn’t provide the complete picture: You could have fat gain and muscle loss transpire in the same region of the body, so measuring the size of that area may not provide an accurate indication of how much muscle you lost, she explains. Body composition assessments, however, account for those types of recomposition.
How to Prevent Muscle Loss
While muscle loss – both in terms of strength and size – is likely to occur if you take a break from your usual fitness routine, there are some measures you can take to decelerate the process. First, maintain movement in your body – even if it’s not as formal of a workout as you’re accustomed to, suggests Olenick. Something as uncomplicated as going for a hike or incorporating a swift bodyweight circuit with air squats, push-ups, lunges, and burpees can aid in preserving muscle, she adds. Merely utilizing your muscles will safeguard them and provide them with a stimulus that communicates, ‘Hey, we’re still utilizing you, stick around,'” says Olenick. “Engaging in any type of activity, even if it appears minimal or solely involves your bodyweight, is considerably better than abstaining completely from maintaining muscle or strength.”
You’ll also need to monitor your calorie and protein consumption – if you don’t have an adequate amount of either, your body will struggle to sustain the muscle tissue you possess, says Olenick. Your body doesn’t necessarily want to relinquish muscle, but it requires a substantial amount of energy (in terms of calories) to maintain, she explains. “If you don’t consume enough, your body will break down that tissue to utilize as energy,” she says. “Therefore, a crucial factor in preserving muscle is consuming a sufficient amount, especially protein.” In reality, individuals who adhere to a higher protein intake, even if they’re not participating in any physical activity, will preserve more muscle compared to those who lack this macronutrient, she adds.
The positive news is that when you return to the gym, you’ll likely regain that strength and muscle mass more expeditiously than it took you to initially develop it. Your muscles contain satellite cells (stem cells that are precursors to skeletal muscle and contribute to hypertrophy) that are generated during exercise, and these cells will eventually evolve into muscle cells, says Olenick. “Individuals who have previously trained will possess a greater number of these satellite cells than individuals who have never trained before,” she explains. “Consequently, you have more ‘material’ to convert into muscle than you did previously.” Furthermore, your body is already acquainted with the movements you’re about to engage in, and your brain has established the neural pathways necessary to execute the skill, so you’ll be able to readapt more rapidly – akin to riding a bicycle for the first time after a five-year break from the activity, says Olenick.
Nevertheless, it’s highly likely that you won’t be able to lift the same weight or complete the same number of sets as you did prior to your break, so take it easy during the first week or two, advises Olenick. During that period, attempt to use a lighter weight or reduce the number of sets for each of your exercises to allow your body to readjust and gradually regain that strength, she suggests.
Most significantly, do not criticize yourself for any power or muscle reduction you do observe, states Olenick. “Grant yourself elegance for whatever reason you were pausing training,” she includes. “You’re back, so what can your body currently accomplish? Do not attempt to compel it to perform what it was accomplishing previously.