# 45 Degree One Leg Hyperextension (Arms In Front O) - Canonical: https://fitwill.app/exercise/10894/45-degree-one-leg-hyperextension-arms-in-front-o/ - Media ID: 10894 - Primary muscle: Glutes - Body part: Glutes - Equipment: Roman Chair - Video: https://fitwill.app/videos/10894/45-degree-one-leg-hyperextension-arms-in-front-o.mp4 ## Description The 45 Degree One Leg Hyperextension (Arms In Front Of Chest) is a unilateral back extension performed on a 45-degree hyperextension bench. Instead of hooking both legs under the ankle pads, you anchor one leg and let the other hang free, then fold your arms across your chest and hinge down before driving your torso back up to a straight line. Taking one leg out of the equation does two things: it halves your base of support and shifts a large share of the work into the glute and hamstring of the working leg, while the erectors of the lower back still control the hinge. This version is a smart progression once standard two-legged hyperextensions feel easy. Because one leg is unloaded, your trunk has to resist rotation and side-bending on every rep, which quietly trains the obliques and deep core along with the obvious hip extensors. Lifters who feel two-legged back extensions mostly in their spine often find the single-leg setup helps them find the glutes instead, since the working hip has to do the extending without help from its partner. Setup matters more here than on the standard version. Your working foot should be secured under the ankle pad, the pad of the bench resting against the back of your thighs just below the hip crease, and the free leg either hanging beside the anchored one or held slightly behind it for balance. If the pad sits too high on your hip, you can't flex at the hips; too low, and your lower back takes over the hinge. Adjust the footplate so your torso can fold forward without the bench blocking your range. Execution should look like a slow bow, not a collapse. Lower until your hamstrings and lower back feel a firm but comfortable stretch, keep the arms folded against the chest the whole time, and rise by squeezing the glute of the working leg until your head, hips, and heels form one straight line. Resist the urge to overextend and arch past neutral at the top, especially on one leg when balance is a factor. This movement fits well as a posterior-chain accessory on leg days or as a hinge variation when your lower back is loaded out from heavier deadlifts. Start with body weight only and modest reps per side, because the balance demand makes it noticeably harder than the bilateral version even before adding load. ## Instructions 1. Set the ankle pad of the 45-degree hyperextension bench so your working leg can hook securely under it with the pad contacting the back of your ankle or lower calf. 2. Position the thigh pad just below your hip crease and adjust the footplate so your torso can fold fully forward over the bench without obstruction. 3. Place your working foot under the pad, leave the opposite leg unhooked and hanging beside or slightly behind the anchored leg, and cross your arms over your chest. 4. Brace your midsection and squeeze the glute of the working leg to set your hips level before you start moving. 5. Hinge at the hips and lower your torso toward the floor under control, keeping the free leg quiet and letting your hamstrings and lower back load into a stretch. 6. Stop the descent when your hamstrings feel a firm stretch and your spine stays long rather than rounded at the bottom. 7. Drive the torso back up by pushing your hips into the pad and contracting the glute and hamstring of the working leg until your head, hips, and heels align. 8. Pause briefly at the top in a neutral line without arching or leaning to one side, then breathe in as you lower into the next rep. 9. Breathe out on the way up and in on the way down, completing all reps on one side before switching legs. 10. Between sets, unhook the anchored leg and shake out your hips before re-securing the opposite leg. ## Tips & Tricks - Keep the pad of the bench against your thighs, not your hip bones; if the top of the pad digs into your pelvis, your hips can't flex and the range shortens. - Resist rotating at the top. If the unhooked leg's side of your hips starts to lift or drop, slow the tempo down and think about keeping both hip bones pointing at the floor. - Crossing the arms over the chest lengthens the lever compared with hands behind the head, so don't pull on your neck if you later progress to that position. - If you lose balance on the free leg, press that thigh lightly against the anchored leg rather than swinging it outward, which tends to twist the hips. - Stop just at neutral at the top. Cranking into a hard arch under fatigue is the most common way lifters irritate their lower back on this exercise. - If your lower back burns before your glutes do, you're likely leading with your spine. Cue the lift as a hip squeeze rather than a torso lift. - Start with the weaker or less coordinated leg first so both sides get equal quality work. - Add external load only when you can control 12-15 smooth reps per side with perfect hip alignment; a plate held at the chest shifts the balance demand considerably. ## Frequently Asked Questions ### Which muscles does the 45 Degree One Leg Hyperextension (Arms In Front Of Chest) work? The glute and hamstring of the anchored leg do most of the hip extension, while the erector spinae of the lower back control the hinge and the obliques fight rotation. It's essentially a one-sided posterior chain exercise with a built-in anti-rotation demand. ### Why do this single-leg instead of a regular two-legged hyperextension? Removing one leg cuts your base of support and forces each side of the hips to work on its own, which exposes and fixes left-right imbalances. Many lifters also feel their glutes more clearly because the working hip can't share the load. ### Is the 45 Degree One Leg Hyperextension (Arms In Front Of Chest) suitable for beginners? Beginners should first master the two-legged version with a controlled tempo. Once that feels stable, the single-leg variation is a reasonable next step starting with short ranges and no added weight. ### How high should the thigh pad be set? The pad should sit just below your hip crease so you can fold fully at the hips. If it presses into your hip bones you'll lose range, and if it sits too low your lower back may round to compensate. ### What should the free leg do during the movement? Keep it relaxed and either hanging beside the anchored leg or held lightly against it. Swinging or lifting it usually twists the hips and turns the exercise into a balance struggle rather than a glute and hamstring drill. ### Where should I feel the 45 Degree One Leg Hyperextension (Arms In Front Of Chest)? Primarily in the glute and hamstring of the working leg, with a stretch through the hamstrings at the bottom. Some lower back work is expected, but sharp spinal discomfort is a sign to reduce range or reset your position. ### What is the most common mistake on this exercise? Overarching past a straight line at the top and letting the hips rotate toward the free-leg side. Both usually come from rushing; slow the descent and pause briefly at neutral to correct it. ### Can I add weight to the 45 Degree One Leg Hyperextension (Arms In Front Of Chest)? Yes, once body weight reps are smooth and balanced, hold a plate or dumbbell against your folded arms. Expect the single-leg balance demand to make the same load feel much harder than it would bilaterally. ### What can I substitute if I don't have a 45-degree hyperextension bench? A standard flat back-extension bench works with the same one-leg setup, or you can do single-leg glute bridges and stability ball leg curls at home to train similar hip extension patterns. ### How many reps should I do per side? Start with 8-12 controlled reps per leg for two to three sets. Because one leg does all the work, match the weaker side's rep count rather than doing more on your stronger side.