We all experience “grooves” and “funks” in our lives -- be it work, reading, socializing, and (especially) exercise.
There are times when going to the gym and crushing a workout seems as easy as breathing, and then there are other times when working out really does feel as hard as it seems.
When we’re in these funks, it’s common to feel a bit guilty for skipping out on exercise as we know it’s something that is incredibly good for us. Even if you don’t feel guilty, you might start to worry that you’re losing muscle and strength during your absence from training.
This fear is more common than you realize, especially with people who embrace the “no days off” mentality.
But, how long does it take for you to start “losing your gains.”
Will one missed workout wreck your progress, or how about one week?
What about an entire month away from the gym?
We’ll tell you exactly how many days you can skip the gym before your body starts to suffer.
But first, let’s start by making a distinction between muscle size and muscle strength.
Size vs Strength
Muscle and strength are often viewed the same when it comes to training, and while they are similar, they aren’t exactly the same.
For example, just because you have big muscles doesn’t inherently mean you are strong relative to your size, and conversely, just because you may appear small, you’re not necessarily weak.
Plus, strength is largely impacted by the neuromuscular system, while hypertrophy (muscle growth) is a combination of volume and tension on the muscle.
In general though, larger muscles have the capacity for greater strength.
Losing Strength
How long you can take a break from the gym without experiencing a drop in strength levels depends on a number of factors, including how long you have been training.
The current body of literature investigating time off from the gym (technically known as “detraining”) indicates that beginners strength levels begin to decrease after 3 weeks of detraining.[1,2,3]
Not only does training experience matter, but so too does age.
Studies using more experienced lifters find that strength levels can be maintained for up to 3-4 weeks, but will significantly decline afterwards.[4,5]
Age Matters Too!
A 2015 study using untrained individuals found that after only a two-week layoff, younger individuals lost ⅓ of their leg strength compared to older individuals who only lost ¼ of their strength.[6]
The takeaway here is that if you go for longer than 3 weeks (21 days) without training, fully expect to see a significant drop in strength and power output.
Losing Muscle Size
Determining how long you can skip out on your workouts before losing muscle size is a bit trickier than assessing muscle strength.
The reason for this is largely due to the tools and methods used to assess the amount and size of muscle a person has.
Typically, when measuring muscle mass, researchers will measure Fat-Free Mass (FFM), Lean Body Mass (LBM), or Muscle Cross Sectional Area (CSA). To measure these variables, they will use tools like a DEXA, bioelectrical impedance (BIA), or MRI.
While these measurements are useful, they can be affected by how much glycogen (stored glucose) is in the muscles.
What this means is that those body compositions measuring tools may not be as accurate as you might think.
For instance, let’s say you take two weeks off from training.
During this time, your glycogen stores will shrink, making your muscles appear smaller, due to a reduction in the amount of water they are holding.
However, while your muscles may appear smaller, you may not have actually lost any muscle mass.
Conversely, you can “trick” the body comp measurement tools into a showing that you are carrying more lean mass than you really are by eating low carb during your “pre” measurement, and doing a high-carb refeed in the days before your “post” body composition assessment -- thereby giving the appearance that you have more muscle on you than you really do.
Fortunately, there are a few studies that have measured water mass in individuals undergoing detraining to help get a better gauge of how quickly you start to lose actual muscle mass.
Similar to loses in strength, you can take up to 3 weeks (21 days) off from the gym before you start to lose actual mass, not just glycogen and water.[2,3]
Maintaining Muscle and Strength
Whether your layoff from the gym is a result of injury or you just get into one of those “funks”, it’s important to realize that you can always regain your lost levels of strength and muscle.
Furthermore, if life gets in the way, and you just don’t have as much time to dedicate to training as you would like, you can breathe a sigh of relief.
Studies show that it is possible to retain muscle and strength for several weeks training as little as one time per week and performing between ⅓-1/9 of your normal training volume.[7]
While this isn’t an excuse to spend more time out of the gym, it should help you to breathe a bit easier during those times of the year when things get crazy (i.e. the holidays) and you can’t hit the gym as much (or for as long) as you would like to.
Takeaway
At the end of the day, taking a day (or entire week) off here and there will not cause you to lose significant amounts of strength or muscle. Furthermore, it’s important to realize that taking one or two rest days per week are important as it allows your body to recover and grow stronger.
If you do encounter an injury or other life circumstance, you can skip the gym for up to 21 days before noticing significant decrements in muscle size or strength.
Realize that these losses are dependent on your age, training experience and many other factors, but for the average person missing a day every now and then is nothing to sweat.
References
- Hakkinen, K., Alen, M., Kallinen, M., Newton, R. U., & Kraemer, W. J. (2000). Neuromuscular adaptation during prolonged strength training, detraining and re-strength-training in middle-aged and elderly people. European Journal of Applied Physiology, 83(1), 51–62. https://doi.org/10.1007/s004210000248
- Ogasawara, R., Yasuda, T., Sakamaki-Sunaga, M., Ozaki, H., & Abe, T. (2011). Effects of periodic and continued resistance training on muscle CSA and strength in previously untrained men. Clinical Physiology and Functional Imaging, 31, 399–404. https://doi.org/10.1111/j.1475-097X.2011.01031.x
- Ogasawara, R., Yasuda, T., Ishii, N., & Abe, T. (2012). Comparison of muscle hypertrophy following 6-month of continuous and periodic strength training. European Journal of Applied Physiology, 113. https://doi.org/10.1007/s00421-012-2511-9
- McMaster, D. T., Gill, N., Cronin, J., & McGuigan, M. (2013). The development, retention and decay rates of strength and power in elite rugby union, rugby league and American football: a systematic review. Sports Medicine (Auckland, N.Z.), 43(5), 367–384. https://doi.org/10.1007/s40279-013-0031-3
- Mujika, I., & Padilla, S. (2001). Muscular characteristics of detraining in humans. Medicine and Science in Sports and Exercise, 33, 1297–1303. https://doi.org/10.1097/00005768-200108000-00009
- Vigelso, A., Gram, M., Wiuff, C., Andersen, J. L., Helge, J. W., & Dela, F. (2015). Six weeks’ aerobic retraining after two weeks’ immobilization restores leg lean mass and aerobic capacity but does not fully rehabilitate leg strength in young and older men. Journal of Rehabilitation Medicine, 47(6), 552–560. https://doi.org/10.2340/16501977-1961
- Bickel, C. S., Cross, J. M., & Bamman, M. M. (2011). Exercise dosing to retain resistance training adaptations in young and older adults. Medicine and Science in Sports and Exercise, 43(7), 1177–1187. https://doi.org/10.1249/MSS.0b013e318207c15d