“Activation” exercises are often recommended at the beginnings of workouts. You might get the idea—whether from random TikToks or from a trainer you pay for their expertise—that activations are necessary to get your muscles firing correctly and able to take advantage of the workout to come. That’s not exactly true, though, so let’s dive in to what activations really do.
What does it mean to “activate” your muscles?
The explanation you’ll hear most often is that our muscles—often specifically our glutes, or butt muscles—“forget” how to fire correctly. But that isn’t really a thing that happens, as physical therapist Tyler Detmer told Lifehacker when discussing so-called gluteal amnesia. Our muscles don’t need specific exercises to be able to contract correctly.
But that doesn’t mean activation exercises are useless; it’s better to think of these moves as warmups with a specific purpose. As I’ve written before, warmup exercises occupy a spectrum from general (like jogging on a treadmill before squats) to specific (doing lighter squats before doing heavier squats).
The warmups that are sometimes called “activation” exercises fall in the middle of that continuum. They can help you to get ready for your heavier exercises of the day, since they’re fairly specific to the muscles involved. If the person who designed your workout is good at their job, they’re a great way to prepare for your working exercises. Unfortunately, not all activations are a good use of your time. So here are some of the cases where activation exercises are useful—and some where they aren’t.
Activation exercises help you “feel” a muscle
If you’re going to do isolation exercises, it helps to know what it feels like to work the muscle properly. Using glutes as our example again, a side-lying leg raise can be done in ways that really use the glutes (when your leg is slightly behind you) or in ways that distribute some of the load to other muscles (like when your leg is slightly in front of you). When you’re doing those leg raises, you can pay attention to whether you’re feeling your glutes—but to do that, you have to know what it feels like to work your glutes.
That’s where activation exercises come in. You do a movement that’s hard to do without using your glutes, and you get to feel the sensations that go along with using that muscle. You might feel a burning sensation as the muscle begins to fatigue, or a tight, full feeling as the muscle fills with fluid (this is what bodybuilders call a “pump”). All of this helps to direct your attention to that muscle and what it feels like. When you do your next exercise, you’ll remember that feeling.
Activation exercises are extra workouts in disguise
The more work you give a muscle, the bigger and stronger it tends to get. We often call that amount of work “volume” and measure that as the number of sets: You’ll build more muscle if you do six sets of squats at each workout than if you only do three.
Activation exercises, if they’re challenging enough, can count toward those sets. Imagine we have two people in the gym: One does three sets each of banded walks and single-leg glute bridges (both often classed as activation exercises) before doing three sets of barbell hip thrusts. The other just does the hip thrusts. That first person is giving their glutes more work than the second, regardless of how the exercises are labeled.
To use activation exercises this way, though, they have to be challenging. If you do your activations heavy enough that you’re at or near the point of failure by the end of each set, they’re adding to your total volume. But if they’re light and easy and you’re just going through the motions, they aren’t really adding anything.
Activation exercises aren’t ever necessary, but they can be helpful
I’ve described a few ways that activation exercises can help in your workouts, but that doesn’t mean that they’re unskippable. You don’t need to feel a muscle working to know that you’re giving it a good workout. And if you’d like to get more volume for a body part, you can do those extra sets before, after, or during your main workout; they don’t have to happen during the “activation” stage at the beginning.
So if you haven’t been doing activations, that’s fine. Just make sure you’re warming up in some kind of appropriate way. (If you’re not sure, read through this guide I wrote to putting together an effective warmup. A warmup is about what gets you ready to work, and it should really be personalized to your body and your workout.)
But if your trainer has given you activation exercises, or if you’ve seen a few you’d like to try online, go ahead and do them. They’ll give you extra work for the target muscle, and you might find that they help you to feel ready by the time you begin the main sets of your workout.
