If you're not the type of person who is anal about measuring and logging what you eat and how much you exercise the easiest way to eyeball the right amount of exercise is to watch the clock. To maintain weight, I work out 30-45 minutes 4-5 times a week. To lose weight, I work out a collective 60-90 minutes 5 times a week. While trying to lose weight, I get off the machine to go drink a few ounces of water and stretch for about 2 minutes every 20 minutes. 2 days on 1 off, 3 on 1 off. I use the elliptical machine with the resistance and incline about half up (8/8 of 15/20 maybe) or I bliss out on the row machine for about an hour and concentrate on my split times. They are dismal but I'm not exactly built for rowing. And I follow the no meal should be bigger than your fist rule. That's been working pretty well. My scale weight isn't shifting much but I look a hell of a lot better when I'm naked.