The peanut gets into each specific segment of your spine rather than the more global thoracic foam roller exercise. This feels really nice for office workers who might be bent over the computer all day and hinging at 2-3 very specific levels in their upper back. Most people will have 2-3 levels that are much more stiff or sensitive than others.
We know that thoracic mobility is an important part of neck and shoulder health. So if you are experiencing neck pain then freeing up your upper back can help with that. It gives your upper back and neck more movement options to work with and this can help tremendously.
Secondly, if you are lifting your arms over head we know that last portions of shoulder mobility and flexibility come from movement of your upper back. So if you are stiff in your upper back and lifting over head a lot then this can help free up your back.
Lastly, it can help your breathing, meditation practice. I love efficiency and getting a two for one deal. So you can try some deep breathing or meditation with the peanut in place. This helps provide some resistance that your breathing has to push against. It also frees up the rib joints that the peanut is resting on.
As always, start light, start gentle, work up to it and give us your feedback.