Cardio advice please
 

I need to lose a minimum of 40lbs more like 60 if I am realistic.

I want to start a cardio routine (walking on a treadmill), but I'm not sure how long and how often.

What is the minimum length of time and the minimum frequency per week that I will need to do cardio to help me to burn fat? I was thinking around 30 mins perhaps 4 days a week? Is this too little to get results?

The minimum cardio you need to do to lose fat is 20 minutes. 30 is of course better. Essentially I think it takes 20 minutes for it to kick in, so anything after 20 minutes (at a time) is a bonus. More fat burning going on.

If you did 30 minutes at the proper heart rate, and then did it twice a day, you are getting double the fat burning for the day. Keeping your metabolism high, reving it up.

4 times a week is not a bad goal. Remember though that you also need to watch what you eat. Cardio burns fat, but not if you keep replacing it. Sometimes we think if we just exercise we will lose. That can be true, but not if you eat extra because the exercise makes you more hungry.

Resistance exercise will help you in some ways more than the cardio. Lifting weights (even if only a few dumbbells) can help to build muscle. Cardio burns fat during the time you are doing it, but by having extra muscle you will burn more calories all the time, even when you are resting, because muscle requires more fuel to maintain than does fat.

So it is good to do both types of exercise. Cardio and weight lifting. But so many weightlifting people have reminded me again and again that "great abs are made in the kitchen not in the weight room", that we need to still pay attention to our diet too.

If you are not accustomed to any exercise ... any exercise is an improvement. The first day try to go as long as you can and then push just a bit. However long that is ... the next time go longer.
Do what you can do, plus a little bit more.

I cringe when I hear that rule about minimum 20 mintes at target heart rate and I'll tell you why. There are people on Earth who's daily exercise is TV to fridge to bathroom to TV to fridge to bathroom etc and eventually to bed. If you tell that fella that he has to exercise at maximum heart rate for 20 minutes a day four times a week, he'll blink and sit down to have something more to eat.

It's eat less and move more, right? Start by moving SOME more and grow from there.

I agree wholeheartedly with Susan B above. There's no defined minimum necessary for fat burning (that's a myth), you need to have your energy output be greater that your calories in to lose weight. One pound = 3500 calorie deficit.

Artemis - I think 30 minutes 4 days a week is excellent. I agree with Susan; don't worry about "fat burning" at this point. I started doing Walk Away the Pounds about twice a week when I first started, and that was about all I could hit. It took me over a month of that to get more frequent, and another couple months to get into the five times a week groove. Don't worry too much about it having to be 30 minutes. If you have 15 minutes before you have to do something else, hop on and get that 15 minutes in. Like Susan says, anything is better than nothing.

Here is a plan that many have had success with

http://www.coolrunning.com/engine/2/2_3/181.shtml