T Nation

Cardio: Thoughts/Discussion

This is a multi-part question. First off, what type of cardio does everyone do while leaning out? Low intensity, moderate or high? Fasted in the morning, pwo, during the day when ever you have time ect…? Most importantly, why?

I’ve been doing some cardio lately and started thinking about all the methods people use while cutting and they all seem to work as long as diet is in order. So, is cardio just a means to expend more calories and wouldn’t matter which method you chose? I’ve heard and read arguments from the low intensity and the H.I.I.T sides, they both make logical and sound arguements.

Last question. I know many people do NOT recommend H.I.I.T while low carbing (I’m pretty sure CT is one of them, would be nice if he came here with some input). I was also under this impression for a while (still am, sorta). My logic was if your low carbing/keto’in then H.I.I.T would just burn glycogen your low on or don’t have (which would be catabolic aka not good).

So as I was doing my low intensity cardio this morning, I thought, why can’t I still do H.I.I.T while low carbing? I still weight lift (which burns more glycogen than a cardio session). So how is high intensity cardio any more catabolic than weightlifting while low carbing?

Sorry for the long winded posts. I’d like to hear everyone’s view points on the topic. This should be interesting.

From what I’ve read/know, the HIIT is harder to recover from when dieting/low carbing. Generally, one would want their body’s efforts to recuperation go towards preserving muscle. I believe that’s why it’s been accepted to do HIIT during the first few/couple of weeks of dieting but reduce it as your calories go down.

Personally, I do intervals 2-3x a week and fasted (few chugs of whey isolate before) cardio 1-2x a week. My intervals, though, are pretty pathetic at times because my legs are generally trashed from leg day. I do the fasted morning cardio because it works for most people and has a proven track record. But I’m bulking. I’ve yet to lean out (only 174 lbs :frowning: So maybe you shouldn’t really listen to me about this.

I know bigger folk will not do intervals often because they’re big and its hard on joints. DC recommends the fasted cardio as does Thibs. Really, the only people I see saying not to do it is “functional” people like Cosgrove.

[quote]Trenchant wrote:
From what I’ve read/know, the HIIT is harder to recover from when dieting/low carbing. Generally, one would want their body’s efforts to recuperation go towards preserving muscle. I believe that’s why it’s been accepted to do HIIT during the first few/couple of weeks of dieting but reduce it as your calories go down.

Personally, I do intervals 2-3x a week and fasted (few chugs of whey isolate before) cardio 1-2x a week. My intervals, though, are pretty pathetic at times because my legs are generally trashed from leg day. I do the fasted morning cardio because it works for most people and has a proven track record. But I’m bulking. I’ve yet to lean out (only 174 lbs :frowning: So maybe you shouldn’t really listen to me about this.

I know bigger folk will not do intervals often because they’re big and its hard on joints. DC recommends the fasted cardio as does Thibs. Really, the only people I see saying not to do it is “functional” people like Cosgrove.[/quote]

I agree with everything you’ve said and have had the same train of thought. I’ve gotten really lean a few times and have never done serious bouts of H.I.I.T. Low intensity does have a proven track record and many (if not most) bodybuilders use it as their method. To play devil’s advocate, why would a high intensity cardio session be tough to recover from, if we’re already weightlifting in a low glycogen state. I would imagine that weightlifting is much more stressful on the body than a cardio session. If glycogen is spared by ketones in weightlifting, wouldn’t the same happen during cardio?

[quote]elusive wrote:
This is a multi-part question. First off, what type of cardio does everyone do while leaning out? Low intensity, moderate or high? Fasted in the morning, pwo, during the day when ever you have time ect…? Most importantly, why?

I’ve been doing some cardio lately and started thinking about all the methods people use while cutting and they all seem to work as long as diet is in order. So, is cardio just a means to expend more calories and wouldn’t matter which method you chose? I’ve heard and read arguments from the low intensity and the H.I.I.T sides, they both make logical and sound arguements.

Last question. I know many people do NOT recommend H.I.I.T while low carbing (I’m pretty sure CT is one of them, would be nice if he came here with some input). I was also under this impression for a while (still am, sorta). My logic was if your low carbing/keto’in then H.I.I.T would just burn glycogen your low on or don’t have (which would be catabolic aka not good).

So as I was doing my low intensity cardio this morning, I thought, why can’t I still do H.I.I.T while low carbing? I still weight lift (which burns more glycogen than a cardio session). So how is high intensity cardio any more catabolic than weightlifting while low carbing?

Sorry for the long winded posts. I’d like to hear everyone’s view points on the topic. This should be interesting.[/quote]

A few years back this really “yoked” dude named SwollCat sent me a personalized diet routine from Cali and he had me on black coffee, liquid carnitine, and an aspirin prior to early morning cardio (had to nix the ephedrine,) but it worked really well. Can’t recall going to crazy on cardio just some easy days and some medium to hard days for about 30-40 minutes about 4x week.

HIIT is faddish to me. A good method of cardio for bodybuilders is the “extensive tempo” workout from the Charlie Francis Training System. Another is incline walking, which Lonnie Lowrie wrote about a few years ago. In general bodybuilders should focus on diet when leaning out and not seek to purge huge numbers of calories through cardio, which is a borderline bulimic mentality to get into.

[quote]belligerent wrote:
HIIT is faddish to me. A good method of cardio for bodybuilders is the “extensive tempo” workout from the Charlie Francis Training System. Another is incline walking, which Lonnie Lowrie wrote about a few years ago. In general bodybuilders should focus on diet when leaning out and not seek to purge huge numbers of calories through cardio, which is a borderline bulimic mentality to get into. [/quote]

I’m not going to disagree with the proof. I know low intensity is a time proven method, but im not refuting that. Im also not talking about doing 45 mins of low intensity and 45 mins of HIIT. Assuming both methods burnt the same amount of cals (LI-350cals & HIIT-350cals). I know Layne Norton advocates HIIT with most of his clients and he has a very good track record.

**Im still doing long bouts of low intensity cardio, but still curious as to why HIIT would be harmful while low carbing? It used to make sense to avoid it, but now that I’ve been thinking of it, maybe its a useful time saving method.

Ive been thinking about this lately as im trying some new stuff, and trying to get keep all my muscle while leaning out. I think the suggestion that HIIT is the the way to go is not necessarily good.

Sure for some people HIIT is going to be what is needed. But the way I see it, when im lifting weights doing super sets and circuits with rest breaks of anywhere from 20-60 seconds between exercises, Im already doing a very intense HIIT workout.

So I like to think of things on a spectrum of both intensity and energy systems. Heavy resistance training would be at one end, while a marathon would be at the other.

Circuit training would be toward the middle, and HIIT on say a bike would be right below that. Then other factors like rest breaks, and work:rest ratios will change things around a bit.

But the way I see it, if your training for max strength, with long rest breaks, then depending on the length of your sets, you are likely only working the ATP-pc system and getting very little cardio effect. For these people, a fast paced steady state cardio would fill in the gaps, and an occasional HIIT session to work on some lactic acid buffering may be beneficial.

Now if you are doing bodybuilding training or anything involving longer sets, shorter sets, then you probably dont need to do as much cardio intensive steady state exercise. You can play around with more HIIT but make sure to keep the intensity a little lower and occasionaly do a steady workout.

I think this works most of the time, as long as your goals are body comp related and not performance based.

Also, I would completely avoid the far right end of the spectrum. The way I see it, any steady cardio over 45 minutes or so is just burning calories. This is going to lead to a desired adaptation and any stress from the workout is going to far outweigh the fitness gains. Instead of wasting the time doing this, just eat less. ((the one exception would be something like long walks or other recovery methods))

Good insight, thanks for replying.

So would you guys say a 30-40 min bout of SS cardio, immediately after lifting, is as effective as doing the same bout of cardio in a fasted state in the AM?

I like HIIT but I have the shittiest recovery/work capacity. I feel like a burnt match the rest of the day if I do HIIT.

I won’t do purely SS cardio but periods of higher and lower intensity, just not necessarily 95% max effort during the “high” intervals. I try to keep my heart rate up and my heart right at the point where it’s popping out of my chest and I’m breathing hard.

Works for me.

I still dont know what to think about the fasted AM cardio. All the reputable sources say not to do it, and that you’ll lose more muscle than fat, but there are plenty of people that have gotten great results doing it.

I think this also relates to the OP question about HIIT while doing low carb. The main question is, are you doing cardio exercise, or are you doing metabolic/cardio conditioning? Is your goal from the cardio to burn fat during the workout, or are you trying to set up a metabolic hormonal environment for future fat loss?

The problem with doing HIIT while on low carb, is that once your glycogen stores are depleted, you have two options for fuel. Stored fat, or stored protein. If you are exercising at a lower intensity (more aerobic) then this energy will come from fat. But if you are exercising at a higher intensity (still aerobic, but with some anaerobic) your going to burn up some muscle for fuel. Not to mention, you are going to cause more microtrauma to your muscles which wont be recovered easily because you are on low carb. These effects would be even further amplified if you were to try to do HIIT after a resistance workout on low carb.

I think the fasted AM cardio is very similar. The only difference is you’ll have a good amount glycogen stored for fuel. You can probably get away with a little higher intensity here, maybe even some moderate HIIT. Throw in some BCAA’s before the workout, and maybe some carbs+BCAA’s towards the end or after the workout and I think fasted AM cardio steady state at a moderate to slow pace could be pretty darn effective.

Lately ive switched to a very high frequency training program, that focuses mainly on anaerobic/aerobic endurance. Im focusing on endurance in the 3-10 rep range, and pretty intense HIIT with 20-30 seconds work and 30-60 seconds rest. Ive also been following nutrient timing, with pre-workout nutrition, a high amount of carbs during the workout with some BCAA’s and a good amount after. In addition to all of that, ive been eating instinctively but trying to make good choices. So far I think this is working quite well.

Ive put on a noticeable amount of msucle in a short time, and even look a bit leaner. There are some things Im going to change though, which will likely be the fasted AM cardio, or ditch the during/post workout carbs on lower intensity cardio sessions. Other than that, I think for many people, a lot can be gained from thinking of working out as training, and eating and fueling for improvements as if its a sport.

I want to take a shot and say that the muscle-wasting argument against fasted cardio depends on the how long you’ve been carrying (and how much of it) LBM, plus your overall level of leanness.

So, if you have a lot of LBM and low bodyfat, and you have gained this LBM recently, your body is probably efficient at storing and breaking down this tissue, vs your fat stores, and so you might be more liable to tap into muscle for energy when performing fasted cardio.

Just a guess, though.

[quote]PonceDeLeon wrote:
I want to take a shot and say that the muscle-wasting argument against fasted cardio depends on the how long you’ve been carrying (and how much of it) LBM, plus your overall level of leanness.

So, if you have a lot of LBM and low bodyfat, and you have gained this LBM recently, your body is probably efficient at storing and breaking down this tissue, vs your fat stores, and so you might be more liable to tap into muscle for energy when performing fasted cardio.

Just a guess, though.[/quote]

Ah, so it goes back to that whole set point theory. Stay at a weight for a while so your body gets used to this weight and your new “homeostasis” weight will be set.

Seems to be common sense to me.

I really don’t see how you’re risking any kind of muscle loss by going for a brisk walk for your morning fasted cardio…are you guys talking about running (or something more intense) for your fasted morning cardio? I could see that maybe risking muscle loss, but not low intensity brisk walking.

[quote]dankid wrote:

I think this also relates to the OP question about HIIT while doing low carb. The main question is, are you doing cardio exercise, or are you doing metabolic/cardio conditioning? Is your goal from the cardio to burn fat during the workout, or are you trying to set up a metabolic hormonal environment for future fat loss?

The problem with doing HIIT while on low carb, is that once your glycogen stores are depleted, you have two options for fuel. Stored fat, or stored protein. If you are exercising at a lower intensity (more aerobic) then this energy will come from fat. But if you are exercising at a higher intensity (still aerobic, but with some anaerobic) your going to burn up some muscle for fuel. Not to mention, you are going to cause more microtrauma to your muscles which wont be recovered easily because you are on low carb. These effects would be even further amplified if you were to try to do HIIT after a resistance workout on low carb.

[/quote]

This is exactly what I’d like to discuss. More so your second paragraph. Most reputable “experts” that I’ve heard from claim exactly what you explained in your 2nd paragraph. I thought it was logical and happened to agree with them. Made sense to me. The body is low on glycogen, HIIT (a glycogen burning task) could burn muscle, so avoid it. OK. NOW, im thinking that ketones (the by products of fatty acid oxidation) would spare muscle from being used, because thats exactly what happens during a weighlifting session (a glycogen burning task) while low carbing. Whats the difference, from the body’s point of view.

After all that thought, Im not exactly SOLD on my own reasoning, but found it interesting to maybe discuss with the Nation here. However, after reading many thoughts on this by Layne Norton, I may be swaying in that direction. His thoughts (which are heavily rooted in research) are that the body would spare muscle during HIIT. He also suggest that HIIT has a significant EPOC that will be more beneficial than an equivalent low intensity session. Finally, he has also claims the HIIT can stimulate cells to produce more mitochondria (the place where fatty acids are metabolized) which in the long run with the help of EPOC, create an enviorment of higher metabolic activity and fat burning.

[quote]elusive wrote:
dankid wrote:

I think this also relates to the OP question about HIIT while doing low carb. The main question is, are you doing cardio exercise, or are you doing metabolic/cardio conditioning? Is your goal from the cardio to burn fat during the workout, or are you trying to set up a metabolic hormonal environment for future fat loss?

The problem with doing HIIT while on low carb, is that once your glycogen stores are depleted, you have two options for fuel. Stored fat, or stored protein. If you are exercising at a lower intensity (more aerobic) then this energy will come from fat. But if you are exercising at a higher intensity (still aerobic, but with some anaerobic) your going to burn up some muscle for fuel. Not to mention, you are going to cause more microtrauma to your muscles which wont be recovered easily because you are on low carb. These effects would be even further amplified if you were to try to do HIIT after a resistance workout on low carb.

This is exactly what I’d like to discuss. More so your second paragraph. Most reputable “experts” that I’ve heard from claim exactly what you explained in your 2nd paragraph. I thought it was logical and happened to agree with them. Made sense to me. The body is low on glycogen, HIIT (a glycogen burning task) could burn muscle, so avoid it. OK. NOW, im thinking that ketones (the by products of fatty acid oxidation) would spare muscle from being used, because thats exactly what happens during a weighlifting session (a glycogen burning task) while low carbing. Whats the difference, from the body’s point of view.

After all that thought, Im not exactly SOLD on my own reasoning, but found it interesting to maybe discuss with the Nation here. However, after reading many thoughts on this by Layne Norton, I may be swaying in that direction. His thoughts (which are heavily rooted in research) are that the body would spare muscle during HIIT. He also suggest that HIIT has a significant EPOC that will be more beneficial than an equivalent low intensity session. Finally, he has also claims the HIIT can stimulate cells to produce more mitochondria (the place where fatty acids are metabolized) which in the long run with the help of EPOC, create an enviorment of higher metabolic activity and fat burning.[/quote]

Well you can’t argue with the results. So i say someone actual performs and experiment of their own, by doing HIIT in a fasted state for fat loss.

[quote]That One Guy wrote:

Well you can’t argue with the results. So i say someone actual performs and experiment of their own, by doing HIIT in a fasted state for fat loss.[/quote]

huh? no one is discussing fasted HIIT.

[quote]elusive wrote:
belligerent wrote:
HIIT is faddish to me. A good method of cardio for bodybuilders is the “extensive tempo” workout from the Charlie Francis Training System. Another is incline walking, which Lonnie Lowrie wrote about a few years ago. In general bodybuilders should focus on diet when leaning out and not seek to purge huge numbers of calories through cardio, which is a borderline bulimic mentality to get into.

I’m not going to disagree with the proof. I know low intensity is a time proven method, but im not refuting that. Im also not talking about doing 45 mins of low intensity and 45 mins of HIIT. Assuming both methods burnt the same amount of cals (LI-350cals & HIIT-350cals). I know Layne Norton advocates HIIT with most of his clients and he has a very good track record.

**Im still doing long bouts of low intensity cardio, but still curious as to why HIIT would be harmful while low carbing? It used to make sense to avoid it, but now that I’ve been thinking of it, maybe its a useful time saving method.[/quote]

Just so you know (if you don’t already), Layne Norton has his clients eating carbs around their HIIT sessions. So I’m guessing he too would not advocate HIIT when low-carbing.

Its one of those things that I dont think is just as simple as “if you do fasted cardio you’ll burn fat, or if you do fasted cardio you’ll lose muscle.”

There are many other factors that are going to affect the outcomes.

I think an extremely important part of the whole equation is carbohydrates and BCAA’s. They both have a protein sparing effect, but the Carbs will potentially take you out of the fat burning phase.

At any given time, if you are in a deficit, you have to assume you are burning both fat and muscle (or protein). You can alter this ratio but you can never really eliminate one or the other. The only goal should be to burn a higher percentage of fat than muscle. If you are burning 75% fat, and 25% muscle, and when you are building you are building 75% muscle, and 25% fat, then you are moving in the right direction.

So the goal of any cardio would be to alter the ratio of fat:muscle loss in a deficit. The trick IMO is though that in any given day you may be in a deficit at times, and a surplus at other times. This is why it is possible to build muscle and lose fat at the same time. Sure not the same instant in time, but the same day.

From what I understand, in the morning, when you are fasted, cortisol is high, and the need for carbohydrates is elevated. You could probably almost argue that doing anything regardless of intensity is going to cause muscle loss with fasted morning cardio. But the intensity will likely affect the rate and ratio of fat:muscle loss.

There are probably a few different options that would work quite well. You could do a shorter more intense HIIT style workout, but drink a shake during or right at the end of the workout containing CARBS and BCAA’s, or you could do a longer lower intensity steady workout and avoid the carbs during the workout, and then move into normal eating after.

I know im kinda rambling on here, because I dont clearly understand this entirely, but its one of those things that nobody probably truly understands.

We all know that in training there are so many different methods that are effective, and I think nutrition is the same way. Im sure a lot of top nutrition specialists like Berardi would advice against stuff like fasted cardio, and intermittent fasting, etc. but you cant deny the results people have been getting for years even decades.

***What got me to give fasted cardio a second thought was a transformation log I saw on bodybuilding.com . It may or may not be real, but the guy got amazing results in a very short time. (i’ll try to post it after if I can find it. He seemed to imply that he felt fasted cardio was a big factor in his success.

Another interesting thing he did, was perform his resistance training after his fasted cardio. I could see how this would work if you payed attention to the timing of nutrients. A 30-60 minute fasted cardio session, followed by a carb + BCAA shake during a resistance training workout would probably burn a good amount of fat, and if you continued to fuel recovery after the workout you could probably hold onto a large amount of muscle while burning a large amount of fat. I’ll post up that link if I can find it though.

[quote]ktennies wrote:
elusive wrote:
belligerent wrote:
HIIT is faddish to me. A good method of cardio for bodybuilders is the “extensive tempo” workout from the Charlie Francis Training System. Another is incline walking, which Lonnie Lowrie wrote about a few years ago. In general bodybuilders should focus on diet when leaning out and not seek to purge huge numbers of calories through cardio, which is a borderline bulimic mentality to get into.

I’m not going to disagree with the proof. I know low intensity is a time proven method, but im not refuting that. Im also not talking about doing 45 mins of low intensity and 45 mins of HIIT. Assuming both methods burnt the same amount of cals (LI-350cals & HIIT-350cals). I know Layne Norton advocates HIIT with most of his clients and he has a very good track record.

**Im still doing long bouts of low intensity cardio, but still curious as to why HIIT would be harmful while low carbing? It used to make sense to avoid it, but now that I’ve been thinking of it, maybe its a useful time saving method.

Just so you know (if you don’t already), Layne Norton has his clients eating carbs around their HIIT sessions. So I’m guessing he too would not advocate HIIT when low-carbing.[/quote]

I’m aware of this. I was reading a thread of his on another board and he said he sees no reason not to do HIIT even if keto dieting. However, he did seem on the fence about it.

[quote]dankid wrote:
Its one of those things that I dont think is just as simple as “if you do fasted cardio you’ll burn fat, or if you do fasted cardio you’ll lose muscle.”

There are many other factors that are going to affect the outcomes.

I think an extremely important part of the whole equation is carbohydrates and BCAA’s. They both have a protein sparing effect, but the Carbs will potentially take you out of the fat burning phase.

At any given time, if you are in a deficit, you have to assume you are burning both fat and muscle (or protein). You can alter this ratio but you can never really eliminate one or the other. The only goal should be to burn a higher percentage of fat than muscle. If you are burning 75% fat, and 25% muscle, and when you are building you are building 75% muscle, and 25% fat, then you are moving in the right direction.

So the goal of any cardio would be to alter the ratio of fat:muscle loss in a deficit. The trick IMO is though that in any given day you may be in a deficit at times, and a surplus at other times. This is why it is possible to build muscle and lose fat at the same time. Sure not the same instant in time, but the same day.

From what I understand, in the morning, when you are fasted, cortisol is high, and the need for carbohydrates is elevated. You could probably almost argue that doing anything regardless of intensity is going to cause muscle loss with fasted morning cardio. But the intensity will likely affect the rate and ratio of fat:muscle loss.

There are probably a few different options that would work quite well. You could do a shorter more intense HIIT style workout, but drink a shake during or right at the end of the workout containing CARBS and BCAA’s, or you could do a longer lower intensity steady workout and avoid the carbs during the workout, and then move into normal eating after.

I know im kinda rambling on here, because I dont clearly understand this entirely, but its one of those things that nobody probably truly understands.

We all know that in training there are so many different methods that are effective, and I think nutrition is the same way. Im sure a lot of top nutrition specialists like Berardi would advice against stuff like fasted cardio, and intermittent fasting, etc. but you cant deny the results people have been getting for years even decades.

***What got me to give fasted cardio a second thought was a transformation log I saw on bodybuilding.com . It may or may not be real, but the guy got amazing results in a very short time. (i’ll try to post it after if I can find it. He seemed to imply that he felt fasted cardio was a big factor in his success.

Another interesting thing he did, was perform his resistance training after his fasted cardio. I could see how this would work if you payed attention to the timing of nutrients. A 30-60 minute fasted cardio session, followed by a carb + BCAA shake during a resistance training workout would probably burn a good amount of fat, and if you continued to fuel recovery after the workout you could probably hold onto a large amount of muscle while burning a large amount of fat. I’ll post up that link if I can find it though.[/quote]

Im not trying to debate whether FASTED cardio is catabolic or not. Im just trying to discuss whether or not HIIT (not fasted) is catabolic while on a keto diet.