What's the ideal length for a cardio session?

[bmwe30is]

I've heard anywhere from 30 minutes to an hour.

What's the ideal time?

Where should my heart rate be if I'm trying to burn off fat?

Thanks!

- Jonathan

[cabezon]

1 1/2 hours at 70%maxHR

less than ideal will be anything that you can do, and in between would be HIT workouts where you do a minute fast and a minute slow for half an hour. Look around for HIT

[bmwe30is]

Thank you sir!

[Sportsmedjosh]

30 minutes really wouldn't be adequate time at all. I would say at the least you should look at around an hour. 45 minutes is when you are going to start using fat as a substrate for energy more efficiently. You can always use 220-age but I would use the karvonen method for finding your target heart rate. It should be on the excel spreadsheet that I posted up. You just have to enter your details and it will do the math for you.

[Sportsmedjosh]

If you're looking to just lose weight here is what I would focus on calories burned is greater than calories consumed. Substrate utilization might be a little over kill at this point.

[cabezon]

I thought it was 90 minutes where the body converts to fat use.

[Soup Nazi]

Takes 12 mins for your body to produce fat burning enzymes.. So the minimum is 45mins I would say.

[Sportsmedjosh]

Jon what have you been doing since you posted?