The Utility of a Well Rounded Gluteus Maximus
The human gluteus maximus is unique with respect to its substantial size and enlarged cranial portion compared to other primates. Our glute max is much thicker and larger—indeed, it is a whopping 1.6 times greater relative to body mass in humans compared to chimps. For those wondering what the point is of having such a well-endowed rear, keep reading!
The human glute max arises from many sites (the iliac crest, posterior sacrum, fascial aponeurosis of the erector spinae on the sacrum, coccyx, and sacrotuberous ligament) and converges onto the iliotibial band and femur. It functions primarily to extend the hip backwards, although its anterior fibers can rotate the femur inwards, and posterior fibers can rotate the femurs outwards.
Using EMG recordings of glute max activity, Lierberman et al. have found it particularly active during running, to keep the body upright instead of flopping forward and to keep the front leg from swing uncontrollably forward. Researchers attribute this activity to the reorganization of gluteal function following hominids’ switch to bipedalism. Importantly, glute max does not simply function as a postural muscle in upright walking—it’s actually a rather quiet muscle during walking—but rather enables many of the quick activities that occur when upright, particularly climbing and sprinting. Expanding on this work, another study by Bartlett et al. confirmed that glute max activity is much larger in running than walking, and even greater in sprinting than running.
The glute max is a key player in running, as well as gluteus medius and gluteus minimus, which are our primary hip abductors. Weak hip abductors have been associated with patellofemoral pain syndrome (PFPS) and iliotibial band syndrome (ITBS), two of the most common running injuries. Fortunately, strengthening these muscles has been found to improve pain in runners with PFPS6 and ITBS. And among novice runners, hip abduction strength greater than normal may reduce the risk of PFPS.
The bottom line: strong hip muscles are a must!
So what can you do? Logistically speaking, it’s difficult to manually muscle test your own gluteal strength. However, you can broadly test your strength by seeing how long you can hold a bridge position or a side plank. From my personal clinical experience thirty seconds is pretty much the bare minimum. You can also perform a single leg step down from a stair ledge and check your position in the mirror. Level hips, knee tracking directly over the second toe, solid trunk, and no sway are what you are looking for.
To strengthen your gluteals, research on maximum voluntary isometric contraction (MVIC) during common therapeutic exercises has shown two exercises in particular to result in the highest MVIC for glute max and glute med.7 In other words, these two exercises will recruit your gluteals the most:
Glute med: Side lying hip abduction
Lie on your right side, and check that your shoulders and hips are stacked. Slowly lift your left leg up towards the ceiling and back down. Because endurance of the glute med is crucial, do as many lifts as you can while maintaining perfect form. Then rest for 1 min, and repeat 2 more times. Complete as many lifts as you can for each set, and repeat on the other side.
Glute max: Single leg squat
Stand on your right leg, and lift your left leg off the floor. Slowly flex your right knee, and slowly straighten back up. Work up to 3 sets of 15 on each leg. Note your form—you should see no aberrant pelvic, trunk or knee motion.