Mystery leg swelling?

shakybabe

I'm wheelchair user so do modified exercises and one of those is on a special set of motorised pedals known as a 'passive trainer' cos it moves my legs for me and I can burn about 320 cals in 30 mins. sometimes I just do this once and do something else like bit of wii for about 200 cals so I get around 500-600 cals. (other days I just do bike for 30 mins in morning and 30 mins after dinner)

I noticed after a few days of intense exercise like twice a day for 2 or more days (and always when its included the bike daily) I get a swelling on the back of my left leg. (just under bottom of butt)

I wasn't sure if it was an allergic reaction at first as at one point i had what looked like purple bruises in that area.. If I rest for few days, drinks loads of water (sometimes take water tablets to help water come off) and take anti-histamines to help swelling go down it goes down nicely and purple blotches disappear completely.. no other area of body swells like this after exercise and usually if I'm allergic to something my mouth or or face will be swollen so it can't be to something I've eaten?

It always comes up in conjunction with having been doing intense exercise for more than 2-3 days in a row on the passive trainer bike. .. any ideas what it could be?

shakybabe

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