Matt Ladewski, owner of Region Barbell Club, performs glute ham raise (GHR) 21's.

According to the Journal of Strength and Conditioning, the GHR exercise possesses the most intense concentric activity and produces significantly more muscle activation than other hamstring exercises. The Romanian Deadlift (RDL) is tied with the GHR and produces the most intense eccentric activity.

To perform GHR 21s, start by doing seven reps of hypers. Bring your torso down toward the ground in full range of motion, push your toes into the foot plate, raise your chest up and squeeze your glutes at the very top. Make sure your torso stays parallel to the ground. As you can see, Matt's body ends in a straight line.

Continue right into seven reps of glute ham raises. Matt puts his hands on his hamstrings and glutes to make sure they are doing the contraction, not his back! You may start to tire out, but don't compromise reps with an excessive low back arch.

Finally, hit seven full-range glute ham raises. This is the combination of the hypers and glute ham raises — they are killer. Again, make sure your glutes are tight when your torso is parallel to the ground, then use your hamstrings to bring you all the way up.

Matt puts the EliteFTS™ GHR foot plate up on an 11" platform to increase the difficulty of the angle.

If you would like do this with yourself, a client, or an athlete, and the the strength level to do essentially 21 GHR's isn't quite there, this could be assisted by looping EliteFTS™ bands around the top of a rack and to the person on the GHR. Move the GHR infront of a rack to attach.

Matt McAllister. "Muscle activation during various hamstring exercises." Journal of Strength & Conditioning Research (forthcoming). POST ACCEPTANCE, 21 October 2013. doi: 10.1519/JSC.0000000000000302.