WM, you might want to add that you should only do this for a few minutes at a time....
foxy, youve joined the gym, which gives you the motivation to work at it, stay with it..
there will be a trained professional at the gym who will advise you going by your weight, build age and target, what to do next,
youll probably find for the first couple of weeks you're best off doing a total of an hour or so gently using cycles and rowing machines walking machines and crosstrainers..
a couple of minutes at a time at the heart rate they work out for you (they meaning the trainers at the gym)
you are quite safe walking the treadmill for an hour, or swimming for an hour, at a relaxed speed, but do not try to cycle or crosstrain for an hour, you wont be able to get out of bed the next morning!!
its all new and exiting when you first join and you want to throw yorself in at the depend (so to speak) and try everything and the more the better...
you have to take it slowly and break yourself in till you know what is improving, and what is harmful to your body...
i replied to your foo question just now, but dont by any means follow exactly what i have said or what anyone else says without consulting a professional, face to face,
your gp can give you basic dietery information and exersize help, free of charge... book a checkup,