Trite answer? Look at the clinical guidelines. Quite an interesting read.http://www.health.gov.au/internet/main/ ... adults.htm
you can choose to open the consolidated document or any of the smaller sections.
Essentially how much exercise you need to do depends on your body weight, amount you eat, metabolism, current level of fitness...... Generally 30min per day at least -4 times per week is recommended for good cardio pulmonary health, you would want to do more than that to lose fat. They've recommended 3-5 hours per week, but the more you do, the more you lose. It's really about energy out v energy in. So if you eat more, you need to do more. If you have good muscle mass and a high metabolism, this will decrease the amount you need to do. If you have lost a lot of weigh you may need to do more to counteract the body's tendency to stabilise it's weight and metabolism.
The picture I'm trying to paint is that it really depends on who you are and where you're at. BUT it doesn't need to be complex. Simply decreasing the amount you eat or making it lower in energy (kj or cal) and increasing your exercise will start you off. Also, the best advice is that it really doesn't matter WHAT you do as long as you START doing something and KEEP doing it.
35kg lost. (November 2005 - October 2006)
15kg gained again (as at October 2010).
Back to the drawing board - Let's do this thing!
"You can't change the winds, but you can change the sails"
"Reach out and take control of what lands in your lap"