What is muscle activation?
Muscle activation exercises aim to wake up muscles that don’t “fire” very well. When fitness professionals talk about a muscle firing, we really mean the ability of that muscle to turn on quickly and do its job appropriately. So, in the case of “glute death” (discussed in Part 2), your glutes aren’t doing one or more of their jobs (extending the hip or stabilizing the knee). This leads to an increased injury risk, especially for your low back or knees. (If your knees bug you when you walk up the stairs, strengthen your glutes!)
Does muscle activation really work?
Let’s look at the research. If you’ve read parts 2 and 3, you might notice that I’m a big fan of research reviews. Research reviews are meta-studies, meaning that they study other studies on a specific topic. What I like about research reviews is that it places the research into context. When you look at one research paper, you might learn that band walks don’t work as well as side-lying hip abduction to activate your glute medius. But another study might say that the glute medius is activated like crazy on the stance leg in the lateral band walk. So what do you believe? Neither party is invested in selling mats for side-lying hip abduction or bands for band walks. They're both trying to do their best to uncover the truth. Research reviews come in handy because they look at a wide breadth of studies (way more than what I have time for) and try to collate the data to come to a broader conclusion.
I’m saying all of this because (as in the example above) research on the efficacy of muscle activation exercises is conflicting. While I was researching for this post, I got to a point where I was just going to say that research doesn’t support muscle activation but that in my experience it can be helpful. (This is called anecdotal evidence and so it should be taken with a grain of salt.) Eventually, I found a 2015 research review that summarizes the findings of 100 articles. This review specifically focused on glute and glute medius activation for the prevention of valgus collapse (that’s when your knee caves in when you’re squatting or landing from a jump or going up the stairs or running), which can be a cause of knee pain and injury. The authors’ conclusion was that it “...appears that targeting hip musculature activation and strength may aid in modifying dynamic lower extremity valgus, which may help to reduce the risk of future ACL injury and PFP.”
Phew! A review of 100 studies said that muscle activation works for valgus collapse. Yes, that is a tiny segment of what you can activate for a workout, but I’ll take it. (This doesn’t mean that other types of muscles don’t do well with activation, it just means I have a full-time job and can’t spend all my time reading research articles.)
In the end, muscle activation exercises are often the types of exercises prescribed by physical therapists when treating an injury or pain. They usually only focus on one muscle at a time and, as such, they are rarely considered a “functional” movement. A functional exercise, at its most basic, is an exercise that replicates something you would do in real life — for example, a squat is a functional exercise for sitting down and standing up. For the most part in your strength workouts, you’ll want to focus on functional movements. But, when you’re warming up, you can include a few less functional muscle activation exercises in order to improve the execution of your functional exercises.
What is movement prep?
Movement prep is any movement that (you guessed it) prepares you for a specific movement pattern. For example, if it’s squat day and you’re planning to do some heavy squats, movement prep might be as simple as doing a few lighter warm up sets or it might be a bit more sophisticated and include an exercise like the squat matrix (see video below), which helps you with squat patterning and activates your lats (the biggest muscles in your back).
As is shown by the example of the squat matrix, movement prep and muscle activation often go hand in hand. Your bodyweight squat prepares you for your heavy squat, while reaching your arms up from the bottom of the squat wakes up your lats, which (along with your core) helps you to stay taller throughout your squat.
Want to try muscle activation and movement prep?
Watch the video below to try some common muscle activation and movement prep exercises that you might want to use on squat day.