One of the most effective techniques I have used to attain a more glute driven squat is to start with a progression:
1.)Just the bar, iso hold in the bottom position of the squat,15-30 seconds, focus on activating the glutes by sitting back into the hips, "pulling" down with the hip flexors, pushing out to the sides of the shoes, tightening the core, "pulling" with the feet, etc. You can mess around with many of these techniques until you feel the glutes turn on and take the brunt of the load.
Isometric squats.
Effects of isometric squat training on the tendon stiffness and jump performance.
Original Link: http://www.ncbi.nlm.nih.gov/pubmed/16328192
Conclusion. These results suggest that isometric squat training changes the stiffness of human tendon-aponeurosis complex in knee extensors to act negatively on the effects of pre-stretch during stretch-shortening cycle exercises.
Would you still do them?.
I think you misinterpreted that study. Look at the entire thing:
Effects of isometric squat training on the tendon stiffness and jump performance.
Kubo K, Yata H, Kanehisa H, Fukunaga T.
Department of Life Science (Sports Sciences), University of Tokyo, Meguro-ku, Japan. kubo@idaten.c.u-tokyo.ac.jp
Abstract
The present study aimed to investigate the effect of isometric squat training on human tendon stiffness and jump performances. Eight subjects completed 12 weeks (4 days/week) of isometric squat training, which consisted of bilateral leg extension at 70% of maximum voluntary contraction (MVC) for 15 s per set (10 sets/day). Before and after training, the elongations of the tendon-aponeurosis complex in the vastus lateralis muscle and patella tendon were directly measured using ultrasonography while the subjects performed ramp isometric knee extension up to MVC. The relationship between the estimated muscle force and tendon elongation was fitted to a linear regression, the slope of which was defined as stiffness. In addition, performances in two kinds of maximal vertical jumps, i.e. squatting (SJ) and counter-movement jumps (CMJ), were measured. The training significantly increased the volume (P < 0.01) and MVC torque (P < 0.01) of the quadriceps femoris muscle.
The stiffness of the tendon-aponeurosis complex increased significantly from 51 +/- 22 (mean +/- SD) to 59 +/- 24 N/mm (P = 0.04), although that of the patella tendon did not change (P = 0.48).[ The SJ height increased significantly after training (P = 0.03), although the CMJ height did not (P = 0.45). In addition, the relative difference in jump height between SJ and CMJ decreased significantly after training (P = 0.02). These results suggest that isometric squat training changes the stiffness of human tendon-aponeurosis complex in knee extensors to act negatively on the effects of pre-stretch during stretch-shortening cycle exercises.
Structurally the muscle and tendon both improved, but only the SJ was positively affected on a performance basis. You see the same thing with EMS or anything else that strengthens muscles without movement. Movements involving reflexive action don't improve unless they're done in conjunction with that type of training. It's not anything inherently wrong with the ISos but they have to be done in conjunction with dynamic movements.
