A Powerful Posterior Chain
Louie Simmons has done an excellent job promoting assistance lifts for the posterior chain over the past couple of decades, but articles describing the variations of each movement are rare.
Here's a comprehensive progression scheme for the glute ham raise, Nordic ham curl, reverse hyper, and back extension.
Positioning the footplate higher and/or closer to the hip pad makes the exercise more challenging, whereas positioning the footplate lower and/or further away from the hip pad makes the exercise easier to perform.
There are several variations beyond those tips, though, and some are more challenging than others:
1 Swinging GHR
The swinging GHR is the most basic form of the GHR and is the easiest to perform. It involves combined hip extension followed by knee flexion.
The momentum generated during the hip extension phase makes the knee flexion phase much more achievable for novice lifters or big guys.
2 Flexed-Hip GHR
The flexed-hip GHR is actually easier to perform than the neutral-hip GHR. Flexing the hip lengthens the hamstring and places it in a more effective position to produce force.
However, this variation shouldn't be thought of as a less effective variation than the neutral-hip version. More reps or more load can be used with the flexed-hips version, and it's usually a wise strategy to strengthen the hamstrings in a lengthened position for improved athletic performance.
3 Neutral-Hip GHR
The neutral-hip GHR is generally the variation that's recommended by experts, but athletes and powerlifters rarely do it in this fashion. Usually you'll see some hip flexion or massive anterior pelvic tilt (which mimics hip flexion) in an effort to make the exercise easier and more manageable.
Keeping a neutral hip and pelvic position during the GHR is highly challenging and shouldn't be underestimated. To be honest, most struggle to perform a single glute ham raise with a true neutral hip, spine, and pelvic position.
In the video you'll notice that I'm anteriorly tilting the pelvis and hyper-extending the lumbar spine.
4 Prisoner GHR
With the prisoner GHR, place your hands behind your head in a prisoner position. This lengthens the external lever arm and makes the exercise markedly more challenging.
Depending on the length of the individual's torso and size of the individual's arms, the prisoner variation seems to be equivalent to holding onto a 10-20 pound dumbbell in terms of difficulty.
5 Dumbbell/Chain/Weighted Vest GHR
Once the previous variations have been mastered, it's time to add load in the form of a dumbbell held underneath the chin, a chain draped over the neck, or a weighted vest worn around the torso.
6 Band GHR
Band GHR's are very difficult but highly effective due to the accommodating resistance. Using a band places a greater load on the hamstrings during the second part of the movement.
This is advantageous because that same part of the movement is inherently weaker due to the way the length of the hamstrings diminishes.
7 Rear-Elevated GHR
The most effective and challenging way to perform GHR's is to elevate the back end of the unit. This augments the torque angle curve so you get constant tension on the hamstrings throughout the entire arc of movement. As a reference, I can perform 20 standard bodyweight GHR's, but only 6 rear-elevated GHR's.
Elevating the glute ham developer on top of a box squat box works well. (In the video, I wasn't able to get full lockout since I was fatigued from filming each of the videos in succession.) Just make sure you go higher and achieve greater knee flexion at the top of the movement.
It's tempting to conclude that the Nordic Ham Curl (NHC) is exactly the same as a GHR. However, the knees remain stationary during the NHC, whereas in the case of the GHR, the knees drop down and the fulcrum is at the thighs rather than the knees, which alters some of the joint torques and muscular efforts.
1 Band-Assisted NHC
Most lifters aren't even close to being able to control the entire lowering portion of the NHC. You'll typically see lifters lower their bodies under control during the initial half of the movement, but this is usually followed by a rapid descent during the latter half.
This descent is accompanied by a sharp drop in hamstrings muscle activation, which is obviously something you don't want.
What you do want is activation under a full range of motion, which is where the band-assisted NHC comes into play. Utilizing a band will enable the lifter to control the entire eccentric portion of the movement, which will strengthen the hamstrings through a full range of motion and lead to more growth.
2 Flexed-Hip NHC
Flexing the hips lengthens the hamstrings and puts them at a better position to produce force. This, in addition to reducing the total ROM and reducing the external lever arm, makes the exercise easier to perform.
3 Neutral-Hip NHC
The neutral-hip NHC is the most difficult NHC variation. Of course, placing the hands behind the head or wearing a vest would make the exercise more challenging, but the majority of lifters will never make it to that level of strength. Keep the hips and pelvis in neutral throughout the movement and lower the torso under control.
Although reverse hyper units are rare in commercial gyms worldwide, it's always a good idea to know how to use them. The reverse hyper is actually similar to a kettlebell swing in terms of torque angle curves and muscular effort. In fact, you can think of the reverse hyper as an open-chain kettlebell swing.
Both exercises require the lifter to firmly grip the implement, which transfers forces from the forearms through the lats and into the erectors, glutes, and hamstrings. Both exercises involve a large eccentric absorption component, followed by an accelerative hip extension propulsion phase.
Finally, both exercises leave the lifter huffing and puffing for air after a set.
1 Single-Leg Reverse Hyper
The reverse hyper is fairly easy to learn, but some lifters struggle during their first couple of encounters with the exercise. Those lifters should try mastering the single-leg reverse hyper prior to implementing the bilateral variation.
Make sure the non-working leg is out of the way of the pendulum. Start with the weaker leg first and then repeat with the stronger leg.
2 Swinging Reverse Hyper
The swinging reverse hyper involves marked flexion and extension of the spine and is mostly a concentric-only movement. This variation seems to be common with Westside powerlifters who want to increase their concentric posterior chain power.
The lifter forcefully propels the pendulum upward during the concentric phase, but lets the pendulum swing passively during the eccentric phase. The spine and hips flex sufficiently forward during this time, and the pendulum reverses due to gravity and passive restraint of the soft tissue of the posterior chain.
3 Strict Reverse Hyper
The strict reverse hyper minimizes load and momentum and is an underutilized variant in strength training circles.
4 Neutral-Spine Reverse Hyper
The neutral-spine reverse hyper is a misnomer in that it's virtually impossible to keep the spine and pelvis neutral during a reverse hyper. However, the goal is to minimize spinal and pelvic motion and generate most of the motion out of the hips.
This requires a huge eccentric absorption phase out of the hamstrings to restrain the pendulum and prevent spinal flexion at the bottom of the movement, as well as a strong gluteal contraction at the top of the movement to limit spinal hyperextension.
The back extension is the most versatile of the common posterior chain assistance lifts. There are dozens of ways that it can be manipulated to target a particular muscle or increase the difficulty.
1 Lumbar-Focused Back Extension
There are times when a lifter might want to target his or her lumbar erectors dynamically. In this case, the top of the pad is lined up with the belly button, and the spine is flexed on the way down and extended on the way up. Hip movement is minimized so that the hip extensors work as stabilizers.
2 Neutral-Spine Back Extension
The neutral-spine back extension does a great job of working the hamstrings, gluteals, and erectors in equal proportions. Keep the feet straight and the spine and pelvis in neutral and move solely at the hips.
3 Glute-Focused Back Extension
If you want to target the gluteals during a back extension, first flare the feet outward at a 45-degree angle or more (hip external rotation). Next, round the upper back and keep it rounded throughout the duration of the set. This is more conducive to posterior pelvic tilt and it takes the erectors out of the equation.
Try to achieve a maximal glute squeeze at the top of each rep and envision driving the hips into the pad during each rep. Also, think of the glutes shortening through contractions to erect the torso on each rep, and remember to keep tension on the glutes during the eccentric phase.
Finally, attain maximum hip extension ROM via a combination of hip extension and posterior pelvic tilt. You won't appear to rise up all the way like you do in traditional back extensions, but you'll indeed be achieving full hip extension in the acetabulum.
4 Dynamic-Effort Back Extension
Louie Simmons also helped popularize the dynamic effort method, which is characterized by utilizing submaximal loads but lifting with maximum acceleration and explosiveness.
In strength training circles, you almost always see the dynamic effort method applied to variations of squats, deadlifts, and bench press, but there's no reason why it can't be applied to other lifts as well.
You may use just body weight or hold onto a relatively light dumbbell while busting out a handful of explosive reps. In the video, you'll notice that I accelerate so fast that my hips rise off the pad.
5 Prisoner Back Extension
Place your hands behind your head in the prisoner position, thereby lengthening the external lever arm and increasing the neuromuscular challenge.
6 Dumbbell/Chain/Weighted-Vest Back Extension
After mastering basic back extension variations, it's time to add resistance via external loading in the form of a dumbbell held at chest level, a chain draped over the neck, or a weighted vest worn around the torso. Strong lifters can do around 15 reps while holding onto a 150-pound dumbbell.
7 Band Back Extension
The band back extension is very challenging. The accommodating resistance makes the exercises increasingly difficult throughout the range of motion and you'll find that the erectors take a beating during this variation.
You may want to place the band in a towel before securing it around the neck for increased comfort.
8 Single-Leg Back Extension
Once bilateral back extension variations have been mastered, progress to the single-leg back extension.
It's important to position the body properly so that there's no lateral shifting or sliding of the body during the set. Make sure to squeeze the glutes at the top of the movement. Start with the weaker leg first and then repeat with the stronger leg.
This list is by no means fully comprehensive. There are an infinite amount of tweaks you can make to each exercise. Moreover, many of these methods can be combined to form additional variations, such as using dumbbells plus bands during back extensions.