Squat jumps are an excellent way to build strength and power in the legs, not to mention the cardiovascular benefits. The traditional approach has to been to use dumbbells initially, then go to a bar on the back when the need for heavier weight arises. The downside to this is that having a bar on the back creates a lot of pressure on the spine - not good in the long term.
Hex bar jump squats, or trap bar jump squats (same beast), take a LOT of the pressure off of the spine, and it makes is much easier to ditch the weight if needed. If you have a hex bar/trap bar, give it a shot.
Saturday, November 02, 2013
The hex bar is a superior tool for performing squat jumps. A study published in 2012 in the Journal of Strength and Conditioning Research found that the biomechanics of a hex bar jump more closely resemble the jumping that occurs in sports. With a hex bar you can jump higher and produce greater force and power than you can with a straight bar. As a bonus, the hex bar jump will also develop the traps as you shrug during the jump.Here is the abstract of the article Poliquin cites:
Swinton, Paul; Stewart, Arthur D.; Lloyd, Ray; Agouris, Ioannis; Keogh, Justin W. L.Citation:
One of the most popular exercises for developing lower-body muscular power is the weighted vertical jump. The present study sought to examine the effect of altering the position of the external load on the kinematics and kinetics of the movement. Twenty-nine resistance-trained rugby union athletes performed maximal effort jumps with 0, 20, 40, and 60% of their squat 1 repetition maximum (1RM) with the load positioned (a) on the posterior aspect of the shoulder using a straight barbell and (b) at arms' length using a hexagonal barbell. Kinematic and kinetic variables were calculated through integration of the vertical ground reaction force data using a forward dynamics approach. Performance of the hexagonal barbell jump resulted in significantly (p < 0.05) greater values for jump height, peak force, peak power, and peak rate of force development compared with the straight barbell jump. Significantly (p < 0.05) greater peak power was produced during the unloaded jump compared with all trials where the external load was positioned on the shoulder. In contrast, significantly (p < 0.05) greater peak power was produced when using the hexagonal barbell combined with a load of 20% 1RM compared with all other conditions investigated. The results suggest that weighted vertical jumps should be performed with the external load positioned at arms' length rather than on the shoulder when attempting to improve lower-body muscular performance.
Swinton, PA, Stewart, AD, Lloyd, R, Agouris, I, and Keogh, JWL. Effect of load positioning on the kinematics and kinetics of weighted vertical jumps. J Strength Cond Res 26(4): 906–913, 2012.
Here is a video of former NFL running back Devon Moore doing trap bar squat jumps.