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45 vs 90 Degree Back Extension Bench: Get the 45

Shopping for a back-extension bench turns up two shapes with overlapping names: the 45-degree bench, which holds your body diagonal, and the 90-degree vertical Roman chair, which hangs your torso straight down. Listings mix the names freely, sometimes calling both a Roman chair. For rebuilding a lower back, get the 45. This guide is the case, and the reason the vertical bench keeps its fans anyway.

The difference in one sentence

On a 45-degree bench, the load on your back starts light at the top of the movement and grows as you hinge down; on a vertical bench, every rep begins at the bottom of the arc, where the lever is longest and the load is greatest.

Why that decides it for a sore back

A recovering back needs a version of the exercise easy enough to start this week. The 45 has one: come up to a supported diagonal and hold. Small shifts in body angle tune the difficulty finely, which is what lets a program move in steps your next-day pain can approve. The program on this site, and the app that runs it, are written for the 45; the four stages do not map onto a vertical bench, because a vertical bench has no easy top position to hold.

The 45 also stays useful after you recover. Pauses, slow descents, and a plate held to the chest keep making it harder for years. You will not outgrow it.

What the vertical Roman chair is actually for

The 90-degree chair is a legitimate tool for trained athletes who want every rep at maximum lever, usually for high-rep conditioning of an already strong back. That is a fine goal, and it is the opposite of a rehab progression. If your back hurts, it is the wrong bench; if you get strong enough to want one someday, your gym probably has one.

Telling listings apart

Ignore the product title and look at the photos. A pad at a diagonal with the feet anchored low and behind: that is the 45, sometimes listed as a hyperextension bench. A tall frame where the hips rest on a pad and the torso hangs vertically: that is the 90. When a used listing says only "Roman chair," the photo decides.

Once the shape is settled, the rest of the purchase is pad position, ankle lock, and weight rating, covered in the bench buying guide. The short version of both guides together: buy a 45 with a solid ankle lock, set the pad at your hip crease, and start with holds.

The app