Recruit the Glutes
I know I must sound like a broken record at times in class, harping on you to use your glutes in multiple poses and through many different transitions. I even have you unceremoniously grab or tap them on the regular! :) Please know that it’s only because I love you and care about the well-being of your body. <3 I simply want to share my knowledge on how strong glutes can change your life. So this week we will cover the big mamma jamma muscle, the largest muscle in your body...GLUTEUS MAXIMUS!!! (PS, I really hope you just said that in a loud, stadium-announcer-like voice in your head, because I sure did.)
The gluteus maximus (GMax) is the largest and heaviest muscle in the body. Its massive size makes it built for power and able to generate a large amount of force. It evolved from a groin muscle that can still be found in lemurs and such. Secondary to changes in the pelvis and the erect posture of humans, the GMax’s function evolved from adduction to extension and external rotation of the hip in order to maintain this upright posture.
Although the GMax is a powerful extensor, it doesn’t work much unless it needs to (which is why we call them snoozy glutes!). So for example, the GMax is not a big mover during normal walking, functioning mainly just to help stabilize the pelvis. It’s recruitment substantially increases with running and even more so with respect to speed, so the faster you run, the more it works. While running, it functions to control flexion of the trunk and extend the hip (aka, maintains an upright posture) and to slow down the swing leg before heel strike. This minimal involvement in walking suggests that the enlargement of the gluteus maximus (from its hip adductor lower primate origin) was likely important in the evolution of our hominid capability to run and run fast on two feet. In athletes, the GMax is among the most important muscles to train due to its action of hip extension which translates into quick, explosive movements. A 2018 study, by Sugisaki et al, looked at the correlation between GMax to quadriceps ratio in faster athletes as compared to slower athletes. Results showed the larger the ratio, the faster the athlete. The stronger the Gmax, the faster you are (according to this study).
It doesn’t work alone in this capacity, however. The two medial hamstring muscles (semimembranosus and semitendinosus) assist the GMax in hip extension. They also work to extend the trunk from a flexed position by pulling the pelvis backwards, as when standing up from a forward flexed position. (This is where I want you to hear my voice in your head telling you to “use your glutes and hamstrings to rise up” from a forward bent pose.) If given the choice between:
a. the largest muscle in your body, GMax, and your massive hamstrings
b. the short, braided musculature of the erector spinae (back muscles)
to hoist the weight of the trunk (~60% of your body weight) back up over the pelvis, which would you pick to win over time? The glutes and hams all the way! Not to mention, they also provide the ability to lower smoothly when bending forward, which is when so many low back injuries are sustained.
The GMax originates from the backside of pelvis, but also has fibrous attachments to the fascia of the gluteus medius, erector spinae, and the sacrotuberous ligament (a flat, fan-shaped ligament that runs between the sacrum and the ischial tuberosity (sit bone)). This strong attachment to the pelvis allows the GMax to function as a stabilizer of the SI joint as well. If there is excessive motion at the SIJ, the GMax contracts, creating a self-locking mechanism and providing an active support system. The strong attachments to the low back fascia create a direct relationship between having a neutral pelvis and the ability to contract the GMax to its fullest potential, secondary to having the optimal muscle length with a neutral pelvis (insert functional movement and yoga!). But GMax doesn’t just extend the hip and trunk.
It also works along with the iliopsoas, piriformis, and obturator muscles (deep butt muscles) to externally rotate, or open the hip. This external rotation also supports the arch of the foot, which is another thing that differentiates us from primates...ok how cool is that? Not to mention, hip external rotation also plays a huge role in controlling the knee joint. Excessive hip internal rotation during running, jumping, and even walking allows the knee to dip inwards and the foot to collapse. The strength of the GMax and the aforementioned muscles to eccentrically control or counteract gravity against excessive hip internal rotation can be a game changer for people suffering from issues like patellofemoral or IT band syndrome.
Some of the best ways to recruit the GMax includes much of what we do every day in our Yoga practice/ functional movement , such as side lunges, single leg deadlift (or Airplane transition), quadruped bird dog, and single leg mini-squats. If you need help to recruit the glutes or can’t feel it, get your hands on them and tap the muscle belly to encourage it to wake up! Nap time is over for the snoozy glutes! And now you know why. :) Until next time, I’ll see you on the mat!