Hello everyone. This is my first time posting, but I wanted to reply to the question about swimming.
It was my husband who had Parkinson's, and although I regularly read the forum when he was diagnosed and struggling and juggling with the usual issues and medications, since he died 2 years ago (suddenly, of a heart attack) I have returned less often, just to keep up to date etc.
About 18 months after diagnosis and a bout of pretty bad depression, we went for a swim at the start of summer. (I live in Greece, so we're talking about sea here, not pools!) He was an average swimmer, but I had noticed the two previous summers that he was very low in the water and seemed somehow not as buoyant as one usually is. Anyway, on this occasion, after a few minutes I noticed his mouth and nose were under water, so raced across the 2 or 3 metres between us. In brief, he was helped out, still conscious, given oxygen and then taken to hospital. It is not like on Baywatch when water gets in the lungs - a few splutters and then back to normal! He was a week in intensive care, and then took 6 months to recover his strength.
The reason I write this is to remind other pd sufferers, perhaps particularly those in the early stages, when walking is not a problem, no episodes of freezing etc - to think twice about where to swim, whether to go out of your depth, and always to have someone with you. When swimming seems so effortless and weightless, it's easy to imagine that you won't have problems moving, but as the poster above found, even treading water needs a certain strength in the muscles, and the water resistance for each stroke may be more than you bargained for, not to mention dizziness which can strike at any time.
Swimming is obviously good exercise, so don't be put off completely. We went again the following year, and if you're not a serious swimmer, but just want to be in the water and paddle around, I recommend a noodle! A metre-long polystyrene tube you can tuck under your arms, either backwards or forwards. It's a great buoyancy aid if you lack confidence in the water, and was very reassuring for me too!