Which one is better: running x miles in 30 mintues, or covering the same distance in 20 mintues?

That sounds a little like “Who’s on first.” Why not ask a trainer or a phys. ed person if you are still in school. And wouldn’t running faster (for as long as you can stay upright) get your heart beating faster and perhaps make it more efficient?

Technically, the best cardio you can do if you are running is to run in bursts.
Sprint for a block, then slow it down, then sprint then slow it down.

Don’t run for less time just because you covered the same distance.

It depends on what your goal is, man.
Are you trying to lose weight? Improve your time? Improve your endurance?

Each one of those would call for a different answer. What are you looking for?

@La chia gomela: hey chica :) *wink
I’m just trying to lose the tire around my waist

MAYBE…just Maybe have a six pack one day*

*Not beer

I agree with some response, it depends on your goals. I run either way, sometimes i just run X amount of miles in 30–45 mins. But usually i try to run X amount of miles in CERTAIN time.

I try to have some light days when i run.. But i normally put some high intensity on it, or something that will really heighten my normal or usual work out.

But i think it is also important to consider how you feel on that day, just to avoid injury and other things. Its always nice to make running as enjoyable as it can be. :)

Just my two cents.

I joined the marathon running clinic here, and the doctor in charge told us to run at least an hour since your body starts burning it’s own stored fat at the 40 minute mark.

If you’re trying to lose weight, then your goal should be burning the most calories.

It turns out that it’s the distance that dictates the calories. If you walk a mile in 20 minutes, you’ll burn ROUGHLY the same number of calories as running it in 10 minutes.

On the other hand, if you run two miles in twenty minutes, you’ll have burned twice as many calories as in the first two scenarios, so generally faster is better, if you can do it.

The quickest way to burn calories is to exercise at a moderate intensity for a LONG time, because if you do high intensity, you’ll burn out quickly, and low intensity you just won’t burn as many calories as moderate. Also don’t forget about interval training!

Three words: Target Heart Rate.

ooh, good point, knotmyday! sometimes i feel like a walking HR monitor commercial when i talk to my friends, but it’s SOOO useful!!!!!