[My Porsche]

Well, there seems to be kind of a debate in the fitness community as to whether high intensity cardio is better at burning fat than low intensity long-duration cardio.

What is the general consensus here? Say 5 miles at 75% versus 15 miles at 40%?

Also, I thought we had a fitness sub-section?

 

[RockadileSX]

Look at sprinters, amazing muscle tone, no fat.
Now look at long distance runners, less than amazing muscle tone, no fat.

 

[OldNick]

Well, lately I have been hearing that the best is the "pulse". You push really hard (the very top of your _workout_ zone) until it nearly hurts, then back off to say, 40%.

Seems to make sense to me. It's probably what our bodies were built to do....walk walk walk. RUN LIKE HELL ! !...walk walk <G>. Feels as if it would make your heart better able to respond to change, was well.

Which is lucky for me because the tracks I usually ride make me do that anyway.....and then some :-<

It's got to be horses for courses though. Depends on body type, age, fitness level etc.

Nick

 

[TLL]

Fitness community?

I don't really think there is much of a debate, really, unless you are a magazine publisher and need to manufacture a controversy in order to sell magazines. Both types of training have their uses.

If fat loss is the main objective, both work, providing you modify your diet. And really, if fat loss is again the main objective, doing both is probably more effective than limiting your self to either LSD or HIIT.

There is a growing body of evidence that shows interval training (such as TABATA intervals) to be very effective in both fat loss and promoting fitness. The nice thing about intervals is that it takes far less time to do an interval workout, and burn an equivalent number of calories, than it takes to complete a long run. Plus it is far less stressful on knees, ankles, etc.

If fitness is your main objective (as opposed to weight loss) then you should be incorporating both into your training regimen as well. Jump over to CrossFit.com and look at how they incorporate both aerobic an anaerobic exercises into their training--you will see that they do both.

I'm really not a believer in the magic bullet--the one "best" exercise, way of training, etc, as promoted by the health magazines. But there are more effective and less effective training programs. FWIW, I think CrossFit has the best program out there.

 

[primoz]

What is the general consensus here? Say 5 miles at 75% versus 15 miles at 40%?

Nothing of this will do much. 15 miles at low rate is way too little to even start burning fat, just as 5 miles at higher rate is (unless you are talking about running not cycling). Fat starts to burn only after more then 30-60mins activity, and making 25km (which is about 15miles) at I don't know, pulse of 110-120 for example, is way too little... afterall with normal biking this is done in a bit more then 1 hour. But I'm talking about some average person, not someone with 180cm and 130kg For someone like this, any movement will do fine for beginning.
Otherwise, high intensity burns more fat, and it burns it more efficiently, but problem is, that it's hard to keep high intensity workout for 2, 3 or more hours.

@RockadileSX: If you measure fat, then marathon runners have much less then sprinters. Sprinters have very visible muscles (I'm not going into how to get that ), and their fat percentage is not high, but marathon runners have fat percentage of 5-6%, which is lower then any other athlete, including cyclists. Of course I'm not saying sprinters are fat, but their percentage is still not that low.

 

[MBMSfreerider]

running either distance is way better than biking it for buring fat since it is harder. i think everyone is right about the main difference being muscle tone. either will burn fat. the big difference is how it trains your heart. aerobic or anaerobically. even if you arent running long enough to actually burn fat you will burn calories and carbs that would later turn into fat if you didnt burn them.
if i had to choose one i would say that low intensity for longer is probably a little better at burning fat because you can keep it going

 

[scuppy]

Training for fat reduction and fat burning are two different things. Improving your fitness can increase the amount of fat you burn throughout the entire day for example. When I did my fitness degree (15 years now), interval training was not considered great for burning fat because it produces by-products that inhibit fat metabolism. The fitness benefit does lead to fat loss, your just not burning as much fat while actually riding. For increasing the actual % of fat utilised as energy during exercise, low intensity (can't remember figures) was the way to go. For all I know more recent studies may have led to a different opinion.