the zinger, HISS

[donluchiti]

So I've recently realized after purchasing a heart monitor, that although I thought I was doing Low intensity steady state cardio, I might be said to be doing High Intensity Steady State Cardio..

With all the articles I've read, from Aragon's really informative dissection of the difference between LISS and HIIT, and a few studies people have linked to me, I'm realizing no one has given an obvious answer about someone who runs at about 75-85% their Heart rate, for like 1- 1.5 hours at a time.

I do this, and prior to buying the heart monitor, I assumed my heart rate was about 50-60% when I was running Steady State, but even when I keep the same relative speed, I am finding my heart rate doesn't sink below 75% when I am running at a maintanable speed. I was under the impression that someone who is consciously going very slow, then exerting all they have is doing HIIT resulting in a jump from around 50% - 85% heart rate in intervals. LISS, I thought was someone basically perfoming at a level they could tolerate for the entire time. When I noticed that my maintainable speed (while still sweating profusly and gulping air) was giving me an average heart rate of 75-85%, I figured I was doing High intensity steady state cardio.

Like I said, my runs are basically steady speed but at that comfortable speed, my heart rate doesn't sink below about 75%. When I do go a little faster at times,(not full bore) my HR is booming at around 85%. Keep in mind, I am a very very avid runner and biker. I've never been diagnosed with heart problems, I just push myself. being that I've always played Hockey and Football, I'd say my legs are no chicken sticks either. I'm jsut wondering if maybe because I run so much and am able to go relativly fast even when 'taking it easy' that my heart rate is comfortable at a higher rate, so in essence I'm still running LISS, just with a heart rate higher than most folks.

[Birddog6424]

I do it all the time. I ran marathons for 16 years, not to mention tons of half marathons and 10k's.

Banging out 60 minutes on a treadmill or elliptical is a walk in the park in comparison.

If you can maintain that, then go for it.

[ndruo]

I imagine this would do wonders for your CV health/endurance.

My question is whether or not it puts you into a state where you're burning muscle?

AFAIK, LISS is intended to keep your heart rate at a level where you consume more fat stores so you hold your lean body mass. HIIT builds lean mass by engaging the ATP process to build those big, fast-twitch muscle fibers.

Seems like you end up burning more muscle than fat with HISS. Pure broscience though, can anyone lend their expertise?

[donluchiti]

Originally Posted by ndruo

My question is whether or not it puts you into a state where you're burning muscle?

AFAIK, LISS is intended to keep your heart rate at a level where you consume more fat stores so you hold your lean body mass. HIIT builds lean mass by engaging the ATP process to build those big, fast-twitch muscle fibers.

Seems like you end up burning more muscle than fat with HISS. Pure broscience though, can anyone lend their expertise?

I worry about this too actually, but from the reading, as long as I'm eating my lean body weight in protein and also doing resistance training a few times a week, I shouldn't lose too much muscle. I reccomend anyone who'd like to learn more about this dichotimy, go checkout Alan argon's thread on LISS vs HITT at http://forum.bodybuilding.com/showthread.php?t=747976 .

I still am a little confused but I found this in Alan Argon's thread, it might be getting at the answer to my question... I wonder if 'ET" Endurance training= High intensity steady state. if it does, damn!

"The body of research strongly favors high-intensity interval training (HIIT) for both fat loss and lean mass gain/maintenance, even across a broad range of study populations [9-12]. A memorable example of this is work by Tremblay?s team, observing the effect of 20 weeks of HIIT versus endurance training (ET) on young adults [9]. When energy expenditure between groups was corrected, HIIT group showed a whopping 9 times the fat loss as the ET group. In the HIIT group, biopsies showed an increase of glycolytic enzymes, as well as an increase of 3-hydroxyacyl coenzyme A dehydrogenase (HADH) activity, a marker of fat oxidation. Researchers concluded that the metabolic adaptations in muscle in response to HIIT favor the process of fat oxidation. The mechanisms for these results are still under investigation, but they?re centered around residual thermic and lipolytic effects mediated by enzymatic, morphologic, and beta-adrenergic adaptations in muscle. Linear/steady state comparisons of the 2 types tends to find no difference, except for better cardiovascular fitness gains in the high-intensity groups [13]. "

Maybe I'll just slow it down a bit...

[Birddog6424]

I think you are misreading it.

Alan Aragon knows that optimal fat oxidation occurs at above 60% and below 89% of max rate. That is the intensity range he is referring to when he is talking about HIIT training. Most people can not maintain that intensity for very long and must do it in intervals.

If you can maintain that intensity for a long period of time you are fine. I do it all the time. But I do it as a cardio workout in a well fed state. I even have an intra workout drink.