Trying to strengthen the gluteus medius? Using clamshells? That may not be such a great idea. 

“Conclusions:

The ABD exercise is preferred if targeted activation of the GMed is a goal. Activation of the other muscles in the ABD-ER and CLAM exercises exceeded that of GMed, which might indicate the exercises are less appropriate when the primary goal is the GMed activation and strengthening.”

J Athl Train. 2012 Jan-Feb; 47(1): 15–23.
Hip Muscle Activity During 3 Side-Lying Hip-Strengthening Exercises in Distance Runners
Joseph M. McBeth, MS, ATC,* Jennifer E. Earl-Boehm, PhD, ATC,† Stephen C. Cobb, PhD, ATC,† and Wendy E. Huddleston, PhD, PT‡

Commentary from our Social media sites:
  • I have done a side-lying leg lift with my heel against a wall for a more effective glute med exercise. IMHO, I think clamshells can work if your hip position is good (balancing on the isis), squeeze thrust at the end of the motion – the problem is, it is really easy to revert to a compensation pattern & rely on the tfl to accomplish the move.
  • The Gait Guys We have not used that one. We usually do weight bearing, 1 legged balance work and mini squats
  • The Gait Guys remember the g med is paired with the contralateral QL. Is she firing there? How does she do with fewer reps/ longer hold times to build endurance?
  • Andy: I’ve been saying this for years – move away from concentric activation in non functional positions and move towards strengthening muscles how they work in function – for runners loading the glute med eccentrically in an upright position makes far more sense.
  • Reader: Interesting. I use window wipers. Basically clamshells with hip extension so that your heel is pressed against a wall. Gmed takes on a stabilizing role and an active role as the primary mover.
  • Found this little video a long time ago and have been using it ever since. https://www.youtube.com/watch?v=K7y_TnADXS4
this one is called windshield wipers and will really blast your glute med and work glute max and…
  • Reader: The glute med is a low load stability muscle. It does not respond to classic high load strengthening exercises. It makes sense that as you increase the load on the glute med the outer moving muscles take over at the expense of the Glute med reinforcing the faulty movement pattern you are trying to correct.
  • Reader: In terms of gait, why is activating the G-Med important? Does the G-Med control internal rotation of the femur, or does it contribute to external rotation of the femur?
  • The Gait Guys It maintains pelvic stability during stance phase.
  • Reader: I have done a side-lying leg lift with my heel against a wall for a more effective glute med exercise. IMHO, I think clamshells can work if your hip position is good (balancing on the isis), squeeze thrust at the end of the motion – the problem is, it is really easy to revert to a compensation pattern & rely on the tfl to accomplish the move.
  • The Gait Guys: We have not used that one. We usually do weight bearing, 1 legged balance work and mini squats
  • The Gait Guys remember the g med is paired with the contralateral QL. Is she firing there? How does she do with fewer reps/ longer hold times to build endurance?
  • Reader: I’ve been saying this for years – move away from concentric activation in non functional positions and move towards strengthening muscles how they work in function – for runners loading the glute med eccentrically in an upright position makes far more sense.
  • Reader: Ive always had a hard time understanding how one can transfer clamshells to functional movement. 
  • Reader: I’ve heard people say that the clamshells get the muscle firing again so it can then be integrated into regular functional patterns, but it never made sense.
  • Andy:Totally agree – I wrote this article 5 years ago which may be of interest http://www.mile27.com.au/strengthening-your-gluteus…/
  • The point is to establish the ability to activate the glute med in isolation. Once that is achieved then one can begin functional exercises to continue to improve glute med function.
  • Reader: Thanks for sharing. I’ve seen and experienced remarkable resolution of patellofemoral syndrome symptoms using functional squat and lunge exercises (a la P90X3, but with great attention to proper form over ROM or reps) that strengthened the glutes far out of proportion to the quadriceps. For sidelying I recommend folks keep the thigh in line with their trunk (i.e., in slight hip extension) as clinically this seems to activate glut med most effectively while preventing hip flexor substitution. Glad there is now evidence demonstrating this.
Reader: To start an activation of Glut med I like this one too – static, but functional (for the standing side, not the flexed one!!)http://www.damiangriffin.org/rehab/stage1/vmowall.htm