Regarding running--if you aren't a runner, yes, trying to go out and run five miles might just do more harm than good. Start slowly--run a block, walk a block, run a block--gradually building up to a mile, then two miles.
Most exercise is going to hurt a bit if you've lived a relatively sedentary life. There is a difference between the pain of "my body isn't used to activity" and the pain of "ZOMG, my heart is going to explode." Pain is just weakness leaving your body.
Most exercise is going to hurt a bit if you've lived a relatively sedentary life. There is a difference between the pain of "my body isn't used to activity" and the pain of "ZOMG, my heart is going to explode." Pain is just weakness leaving your body.