Dow, I like the question. Unfortunately with most questions I like I don´t have the answer. But maybe I can help with why swimming is better than other sports.

I couldn´t understand why I had been told that tennis and volleyball were recommended (yet they hurt me in the days after I did them) and other sports ie. contact sports I was told to keep away from. Eventually between here and my physical therapist I have worked something out that works wondors for me.

Sports like tennis are called impact sports because of the sprinting and jumping and hitting (ball). All of this crunches and jars the bones and causes alot of discomfort for us afterwards. Volleyball is worse and contact sports are worse again.

This is why swimming is so much better than most other sports since you get a good range of movement without any of the above problems. There are still certain movements in the pool which are detrimental depending on your problem. For me I don´t do legs of breast stroke or the butterfly at all.

Cycling doesn´t cause me any discomfort and walking is generally very beneficial. I also do light jogging as I enjoy it and have been told that in moderation it mightn´t cause problems and this is what I have experienced.

I have learnt the hard way that I should keep all conversations with doctors to their specialities e.g. drugs. Sport is not their forte and what exercise I should do, I shall ask someone else.

As to your question, why does swimming actually help AS, I haven´t the faintest idea.

Back to the point of this post, I jogged 6km in 39.42 minutes and cycled 12km+/- in 20 something minutes.

Over and out