The human body has an amazing ability to adapt. In the realm of physical fitness, this can be a good thing and a bad thing—it’s good because it means the body can become stronger and adapt to taking on greater challenges, but it’s bad because it means your workout needs to evolve all the time.
Many trainers and fitness gurus tout the idea of muscle confusion—frequently doing different workouts in an effort to keep your body guessing what it’s going to have to do next.
The problem? The science just isn’t there to support muscle confusion as a practical training plan. However—and this is important—that’s not to say variety and progressive overload aren’t important parts of your fitness routine. Just don’t count on them to “confuse” your muscles.
When you incorporate variety into your workout, you’re hitting more muscles and reducing your risk of overworking (and thus injuring) any part of your body.
The American Council on Exercise explains that your muscles need approximately 48 hours to get back to their full strength after an intense workout, which is why some people alternate the muscles they work on different days of the week; for example, they’ll do an upper-body workout on Mondays, Wednesdays, and Friday, and they’ll do their lower-body workouts on Tuesdays and Thursdays.
Mixing it up is also just as important for your mental approach to exercise. A December 2019 study, “The effects of exercise variation in muscle thickness, maximal strength, and motivation in resistance-trained men,” published in the peer-reviewed journal PLOS, saw two groups of men given either a routine with fixed exercise selection or a varied session. Both men gained muscle, but the group that had variety in their workout reported more motivation to exercise.
It’s also important to remember that there’s more than one way to challenge yourself when it comes to exercise. According to the International Sports Science Association (ISSA), you can improve your fitness by increasing your workout’s intensity, duration, or type. An endurance athlete, such as a runner or cyclist, might opt to go for a longer distance at the same speed instead of upping their speed and going for the same amount of time. Likewise, somebody who is strength training could lift a moderate weight load for more reps or a heavier weight load for fewer reps.
Any of these options will present you with a new challenge and help you get in better shape—just don’t expect your muscles to be confused in the process.