5 Exercises to Increase Your Sumo Deadlift and Posterior Chain Size
The Sumo deadlift is an acceptable competition lift in powerlifting and is commonly used by powerlifters who squat in gear and/or with a wide stance. When performed appropriately, the sumo deadlift can pack some serious mass onto bodybuilders looking to achieve a balance of muscular size and symmetry.
The sumo deadlift is a compound movement targeting the erector spinae, a group of muscles running vertically along both sides of the spine. The erector spinae is comprised of three heads - the Iliocatalis, Longissimus, and Spinalis.
The erector spinae assists in extension, lateral flexion, and rotation of the lumbar, thoracic, and cervical spine as well as the neck.  Strong erector spinae muscles will minimize the likelihood of back injuries and strains as well as improve your overall physical performance.
The gluteus maximus, adductor magnus, quadriceps and soleus are the supporting muscle groups assisting the target muscle during the movement. The hamstrings and gastrocnemius, trapezius (middle, & upper), levator scapulae, rhomboids, and abdominals (rectus abdominis and obliques) act as stabilizers during this exercise.  Stabilizer muscles help maintain a posture or fixate a joint by contracting without significantly moving. 
The Sumo deadlift is most commonly performed using a barbell but can also be completed using a dumbbell or kettlebell. The five exercises outlined below are going to not only going to increase your sumo deadlift strength but are also bring up the lagging muscle groups used to execute the pull.
The 5 Best Exercises for Increasing Your Sumo Deadlift
#1 - Sumo Deadlift VariationsVariations of a lift are undoubtedly the most effective exercises for improving your strength and form on that lift. Instead of adding exercise after exercise with questionable carryover, start first by adding in sumo deadlift partials, pauses, and lockout holds.
While these exercises may not be the most glamorous, they effective at reinforcing proper form, exposing muscle weaknesses, bringing up muscle imbalances, priming and overloading your central nervous system, as well as helping you power through mid-repetition sticking points.
Increase the load and decrease the exercise's range of motion to blast through sticking points. Do you always find yourself struggling to lock out the sumo deadlift after the bar passes the knee? Then set the support pins so that the bar is resting at or slightly above knee height.
Practice driving your hips through, keeping your torso as upright as possible, abdominals braced, and pushing through your heels. With this safety catch you can perform more repetitions and/or use more weight with decreased injury risk. Since you're using more weight consider using high quality straps like Versa Gripps.
Paused repetitions are rarely used in deadlift programming but can be extremely effective in helping you to add plates to the bar and muscle to your body. Unlike partial reps you'll quickly find that paused reps increase the intensity of the sumo deadlift without requiring additional weight on the bar. At some point during the movement pause for 1 to 5 seconds before continuing with the repetition.
In the case of sumo deadlifts, many lifters choose to pause immediately off the floor and when the bar is at or slightly below the knees. During this pause focus on engaging the target and supporting muscle groups while staying as tight as possible. Incorporating pauses during your warm-up or back-off sets are an excellent way to increase time under tension, induce hypertrophy in the posterior chain, and jack up the heart rate.
For a truly brutal exercise, try the double pause deadlifts, popularized by Greg Nuckols of Strength Theory. Instead of pausing one time during the pull, pause when the barbell is immediately off the floor and when it's at knee height. You may have to substantially decrease the working weight but the payoff will be exceptional.
Lockout holds are excellent for building confidence with heavier weights. let's say your one repetition maximum is 475 but you're yearning for the coveted 495lbs - 5 plates per side. Build confidence with this heavier weight by setting the pins at or slightly below the lockout position, loading up the bar, setting your starting position, unracking the bar, and holding the lockout position for 5 to 15 seconds.
This technique will help you break through the psychological barrier of a heavier weight, prime your central nervous system for your working sets, as well as increase upper back size and strength.
#2 - Wide Stance Leg Press
The sumo deadlift requires a stance much wider than shoulder width, which dramatically increases the involvement of the glutes and hamstrings. There are few exercises in which you can use this wide stance, and even fewer that can safely be performed to failure. The wide stance leg press is one of those few exercises.
The benefits of this exercise include the ability to blast your hamstrings, glutes, and quadriceps, isolate your lower body, support your lower back, and decrease the risk of injury if training to failure. The goal with this exercise is to mimic your sumo deadlift stance as much as possible, so take a stance as wide as the platform you're pushing against will safely allow. Throughout this movement it's crucial to keep your knees and toes pointing in the same direction, to press through your heels rather than your toes, and to ensure your knees don't cave in.
Compared to the conventional stance leg press you may experience a significantly increased exercise range of motion. The wide stance leg press is an excellent exercise to perform immediately after sumo deadlifts or as a finisher at the end of your workout to annihilate your glutes and hamstrings. In addition to widening your stance, placing your feet higher on the platform will further shift emphasis from your quadriceps to the glutes and hamstrings.
#3 - Hip Thrusts
If you struggle to lock out your sumo deadlift then chances are your glute strength is sub-optimal. Hip thrusts are brutally effective in improving lockout speed and strength as well as inducing hypertrophy of the glutes, hamstrings, and lower back.
Before performing hip thrusts you should be able to successfully perform cable pullthroughs and weighted glute bridges. Sit down on the ground so that your shoulder blades are resting on the center of the side of flat bench, your glutes are touching the ground, your knees are bent, feet are shoulder width apart and flat on the ground. Roll the barbell so that it's above your hips.
Place a squat pad, yoga mat, or foam exercise pad in between the weight and your hips to minimize discomfort. While keeping your upper back in-contact with the pad and feet flat on the floor, engage your glutes, push through your heels, and extend your hips. Continue extending your hips until they're in-line with your knees and upper body. Hold at the top for 1 to 5 seconds to increase intensity.
Slowly lower the barbell and repeat. For the ultimate glute burn hold the last rep of each set as long as possible. Weighted hip thrusts are an excellent warm-up or finishing exercising that will shape your butt and have to pulling heavier in no time.
Make sure not to excessively arch your back in pursuit of greater range-of-motion. This will only lead to potential back pain so keep your core engaged throughout the exercise.
#4 - Low Pulley Cable Pullthroughs
The low pulley cable pullthrough is a lower back friendly exercise that's easy to set up, reinforces the proper hip hinge movement pattern, as well as leave you with serious glute delayed onset muscle soreness (DOMS) if performed correctly. Set the pulley of an adjustable height cable tower to the lowest possible height and attach the double-knobbed rope handle.
Take your sumo deadlift stance and face away from the cable tower. Grab the handles with an overhand grip below the knobs and take three to four steps away from the tower.
Keeping your arms straight slowly allow your hands to drift back towards the tower through hinging at your hips. Your shins should stay perpendicular with the ground but your upper thighs and hips will move. Stop when you feel a nice stretch in the glutes and hamstrings.
Continuing to keep your arms straight initiate with the glutes and squeeze them, driving your hips forward until your torso is upright and hips are fully extended. Pullthroughs are great as a warm-up, superset, or finisher exercise using sets of 12+ repetitions. They can also be performed on cardio and upper body workout days to practice the hip hinge motion without significantly impacting recovery.
#5 - Power ShrugsIncorporate power shrugs if you're having trouble keeping your chest up and upper back tight during sumo deadlifts. These will blast the trapezius muscles in your upper back as well incorporate the posterior chain for stabilization. Unlike conventional shrugs you'll be performing these in an explosive yet controlled manner; this will allow you to use more weight and perform more reps.
Begin by setting the rack pins so that the barbell is resting between knee and mid-thigh height. After loading up the barbell with the desired weight, take a pronated (palms facing you) grip slightly wider than shoulder width. Brace your abdominals for impact, unrack the bar, and in an explosive shrugging motion simultaneously raise your shoulders and upper back towards your ears while also extending your hips and ankles. you'll be using a significantly heavier weight than what you use on conventional shrugs so don't worry about holding at the top.
After the explosive raising of shoulders and extension of the hips and ankles allow the weight to return to the starting position. These can be perform using a barbell, dumbbells, kettlebells, or Smith Machine.
Straps are advised on this exercise; this exercise should smoke your traps and upper back, not your grip. Some of my favorite power shrug rep schemes involve 10-rep drop sets, 100 rep rest-pause sets, ascending, and descending pyramids.
References1) Griffing, James, et al. "Erector Spinae. ExRx.net. N.p., 2016. Web.
2) Griffing, James, et al. "Barbell Sumo deadlift." ExRx.net. N.p., 2016. Web.
3) Griffing, James, et al. "Kinesiology Glossary." ExRx.net. N.p., 2016. Web.