I try really hard not to judge people who are at least getting some physical activity, especially if they are elderly or are otherwise disabled in some way, but I honestly cannot condone people who give you dirty looks for lifting heavy and sweating while they read Reader's Digest on the recliney bike. If you can read and you are an otherwise functional human being, you can push yourself harder. Most grating are the guys who look the same as they did last year, doing one-arm chest flies on the Nautilus machines while holding and reading Esquire with their other hand. I mean, really?
1) eat real food - more vegetables, moderate meat, moderate fruits, less grains, less sugar, less vegetable oils.
2) exercise - moderate intensity cardio, sprinting, heavy lifting, dedicated stretching and mobility.
3) live - relax, de-stress, meditate.
Disclaimer: I'm not professionally qualified to make any formal recommendations. I've just done my homework and I'm my own guinea pig. All of my data, unless otherwise cited, comes from a sample size of n=1 (me).