Sumo Deadlifts and Box Jumps

Today’s WOD Sumo Deadlifts and Box Jumps SWOD 5 x 3 Sumo Deadlift 4 x 8 Straight Arm Pulldowns   At liftoff the trunk angle is considerably more upright in sumo lifters. My speculation is that by having a more vertical body posture, sumo lifters will experience more leg activity and less activity in the erector spinae muscles. This hypothesis corresponds well with many EMG studies that showed more activity from the vastus medialis and vastus lateralis in the Sumo style. A number of  subjects over the years had a greater one rep max with conventional, but at a percentage of their max did more reps using Sumo. Could this be coincidence or could the different styles emphasize different muscle groups with different fiber makeup? Some similarities are apparent early in the lift (the first pull). In both styles knee and hip angle both increase, indicating a dominance of knee extension over hip extension during this segment of the lift. During the top portion of the lift (the second pull), mostly hip extension is noted, although this is more pronounced in the conventional style. WOD 12min AMRAP 5 Box Jumps (30/20) 10 KB Swings (53/35) 15 Med Ball Sit Ups (20/14)]]>