Back Extension (on Stability Ball, Arms Down)

Back extensions target extending the back and aligning the upper body with the lower body. The latter is also a function of the glutes and hamstrings, comparable to a deadlift. Performing the exercise on a stability ball places the emphasis on extending the back and therefore also on engaging the erector spinae. You cannot sink as far, which limits the engagement of the glutes and hamstrings. At the same time, these and other muscles are required to perform more stabilizing work to maintain position.

Back extensions (on stability ball)

Main muscles:

Erector spinae ('back extensor')

Hamstrings (biceps femoris, semitendinosus, semimembranosus)
Glutes (gluteus maximus, medius, and minimus)

How to perform back extensions (on stability ball)

Lie face down on the stability ball with your legs almost extended and your toes firmly on the floor.
Make sure you are lying stably
Cross your arms over your chest
Lower your upper body as far as possible without making contact with the floor
Extend your spine by pulling your upper body back up and bringing it into line with your legs.

Back extensions (on stability ball) technique

Do not position yourself too high on the ball. You are not training your forehead by falling onto it. Stretch your back, but do not overextend it. Bring your back and legs into alignment as when standing upright. Do not extend them further with an exaggerated hollow back. This adds little to the effectiveness of the exercise and increases pressure on the spine, resulting in a higher risk of injury.