T Nation

Fasted Morning Cardio


Hey guys, new year, new start.

Been wanting to add morning fasted cardio to my routine to speed up my fast loss and increase my conditioning.

I plan on a session every morning before work and then my normal lifting routine after work.

My question is...

Do i stick with 45mins of steady state as Shelby has posted about.


20 mins of HIIT everyday

or Alternate them.



IMO FMC should be the steady state, non-intense variety that you can do over a long period of time (45-75 minutes as Dr. Lonnie Lowery discussed in the MAG-10 pulse fast article) that you can recover from easily. HIIT FMC will probably eat up your muscle.

incline walk, walk outside or go on the elliptical. ride a bike if you want but I could never do it without burning my quads up.


First of all, I wouldn't start out by doing FMC everyday.

If you jump right in with 45-60 minutes a day every day where do you go from there when things stall?

I would recommend starting with 30 minutes of low intensity SS cardio 3 days a week or so and then gradually increase the duration or add extra days when fat loss slows down.


Ok cool, thanks guys. So HIIT is out of out the question for what i wana do.

@Greg i was thinking about what u said before u said it actually.

But on the otherhand does it not just cone down to cals in vs cals out?


Nope, it's not that simple if you're talking about body composition.

HIIT- runs off of glycogen, so you don't want to perform it on an empty stomach, or when you're not in a well fed state (not if you wanna keep your muscle).

SS- while the whole empty stomach being more beneficial aspect is still open to debate, a good number of coaches feel it may improve your insulin sensitivity throughout the rest of the day (why I do it despite not actually buying into the whole 'fat as fuel' notion). Also, it's not as taxing, which is why you can make use of it in an unfed (or BCAA/Mag10 fed) state.



If you used some BCAAs before doing fasted HIIT, could you prevent losing muscle?


Long duration and not interval. Interval on off days after food.

Add it slowly. there was an article about incline treadmill walking or just walking in general. Even has progressions for you. No need to even think if you dont want to. Dont start with so much as others have said. You have no where to go but up when your weight stall. Same with calorie lowering. Do it gradual and alternate adding cardio and lowering cals


Sure, but the possibility of losing muscle is still there, and your workouts will also suffer if you do HIIT too often. You don't want your gym performance to drop off drastically... that's a sure-fire way to lose muscle. The long-term approach, i.e. morning cardio/walking or post-workout cardio/walking, is the better bet to make sure you retain as much muscle mass as possible.


What worked great for me was taking 5grams of glutamine and 10 grams of BCAA and a cup of coffee 1/2 hour before the gym. Like many have said IMO 2-3x a week of FMC is more then enough and you should not go beyond that! It did speed up fatloss for me but i never did HIIT only 45 minute sessions where i never went over 65% of maximum heart rate!


Even during strenuous activities (ie. weight training), when the body does use SOME BCAAs in addition to glycogen for meeting its energy needs, it only amounts to about 15%. Would you risk losing the muscle knowing you've only covered 15% of your energy needs?



Thanks, HIIT is off the cards for now,

Im guna start with 30 mins 4 times a week, for maybe 2 weeks and see how it goes then up it to 40.. 50 until i hit an hour.

Then when then stops add in a 5th day. Before i jump on the bike im taking BCAA's as well.

I currently following a low car diet as well, not keto but probably around 150g of carbs a day.

Will this affect anything?


Mods took the link down when I posted it so I guess i can cut/paste the article instead....

Cardio For Fat Loss: High Intensity Interval Training Cardio Vs Low Intensity Steady State Cardio

Why is it that cardio is always the hot topic of fitness discussion and seems to be the fix all solution to burning fat?

As we have all learned and I have written about in the past that cardio is not the fix all solution when it comes to body compositional changes anymore. New times have rolled in and we have tons of research studies proving that weight lifting is far more superior for fat loss and body compositional changes. But, even though we have these new findings, people still don?t get it and people still want to sit on the bikes reading magazines about Kim Kardashian?s divorce for hours and hours. Do as you please, but I know I?m one of those types of people that want to get the most bang for their buck when it comes to training. This leads me to write about what is the right type of cardio for you?

I will be doing a comparison on HIIT cardio vs LISS cardio, since these two forms of cardio are used the most. By the end of this article you will have a really good idea of what kind of cardio is right for you and how to effectively use it.

What in the world do these crazy acronyms HIIT and LISS mean?

HIIT stands for High intensity interval training, which consists of short sprint intervals coupled with low-moderate intensity work. An example of this would be a 30 second sprint followed by a 4 minute steady pace walk to cool down and bring your heart rate back to normal and then repeating it. LISS stands for Low intensity steady state cardio, which consists of purely low-moderate intensity work. An example of this would be walking on the treadmill or riding the bike and being able to hold a conversation (we tend to see a lot of this at gyms).

Now that you have a basic understanding of the two forms, let?s dive into some more detailed stuff.


Why testing the lactate threshold (LT) and anaerobic threshold (AT) is a good idea? The AT and LT are extremely powerful predictors of performance in aerobic exercise (cardio). There are 2 ways that muscle can burn glucose (blood sugars) and that is through aerobic work (with air) and anaerobic work (without air). For example, long bouts of LISS cardio is considered aerobic work and weight training or HIIT cardio can be classified as anaerobic work. The AT and LT are a great test for HIIT and LIIS cardio because it gives a great predictor of which type of work produces ATP (Adenosine Triphosphate). ATP is a quick burst of energy that we get in our muscles when we contract them (Ex: every time you do a bicep curl, you are getting a quick burst of ATP). HIIT produces better changes in exercise capacity as opposed to LISS cardio. High intensity training will hit the AT and LT, that?s what causes the body to make metabolic changes. When you are doing LISS, you are considered below the AT and LT.

A simple test is being able to hold a conversation while doing cardio. When doing HIIT you are above the AT and LT and when you are above the AT and LT you push for greater improvement in metabolism which thus leads to better fat loss over time.

How can you change your metabolism?

(1) If you want to change your metabolism, you have to increase muscle mass and increase your muscle?s oxidative capacity. Your muscles have these energy producing units called ?mitochondria? and this is where ATP are made and fats are burned.

The more mitochondria you have and the more active they are the greater oxidative capacity you will have for fat loss. HIIT increases mitochondrial capacity and you actually increase the amount of mitochondria you produce. Studies show that you get greater fat loss through high intensity training because of the increase in oxidative capacity. Whereas with LISS you?re only burning calories at that precise moment, there?s no 24 hour energy expenditure (boost in metabolism) and it hurts you down the line because your body adjusts to it and you end up needing more to lose fat. With HIIT your burning calories at the moment but you actually change the muscles metabolism and it boosts your metabolism because you increase the mitochondria density of your muscle, so you increase the muscles oxidative capacity and you really do burn more calories. What most people don?t realize is you have to put your body in an uncomfortable mode and use the max energy expenditure.

It?s supposed to hurt when you?re doing HIIT and if it?s hurting, you?re in an uncomfortable mode and that means you?re doing it right.

The body is very adaptive

(2)We tend to see a lot of people doing hours and hours a week of LISS and according to calculations they should be losing pounds, but they can?t lose anything because your metabolism adjusts to low intensity exercise. It just doesn?t cut it because it?s just a calorie burn at that time, not 24 hour energy expenditure. If you do LISS all the time, you?re basically trading calories in and calories out and you can cut these same calories through diet and still get the same effects.

Ex: You burn 200 calories over 30 min of LISS, you can cut out 200 calories through carbs or fat and get the same effect as opposed to getting a 24 hour energy expenditure through HIIT cardio.


(3) A study conducted by Wilson et al. From the University of Tampa, FL, shows when you add in LISS you get a temporary boost in weight loss. Subjects lost a couple of pounds the first week and after that they lost nothing. This happened because their metabolism completely adjusted to that and that became their new set point to what they had to do just to maintain. LISS with a low calorie diet is terrible for fat loss and could cause muscle loss. During a low calorie diet, LISS cardio is more catabolic (muscle wasting) towards muscle as opposed to HIIT cardio being much more muscle sparing.

The reason being that your metabolism gets so adjusted to LISS and you constantly have to do more and more and people don?t understand when you are on a low calorie diet, it usually ends up being low carb, so once you are glycogen depleted (stored carbs in muscle), your body is going to look for energy to rely on and guess what it goes after? Protein! Once it goes after protein, then you start to see catabolism (muscle wasting).


Now I know a lot of you have gotten the hint as to why HIIT cardio is more advantageous to LISS cardio for muscle retention and fat loss and it seems as if I totally bashed LISS cardio to the ground.

But, keep in mind that this doesn?t mean that LISS is useless. I?m a big believer in doing both HIIT and LISS combined. Here are the following reasons why:

You can?t do HIIT 5-6 days a week because eventually it will have a negative impact on your weight training and interfere with growth
Many people have legitimate orthopedic, cardiac, and even psychological reasons to avoid HIIT, so LISS is their only option
HIIT could be dangerous if not used right and could lead to injury
HIIT and LISS on either a combined, cyclical, or rotational basis seems to be the best formula in my opinion

So to sit there and say that HIIT is hands down more superior than LISS for improvement in body composition is as bad as saying that 6 reps per set is better than 20. I?m a firm believer that both HIIT and LISS cardio have unique benefits unto themselves. I feel they both should be incorporated into your routines since each have specifically different effects.

The Bottom Line

Do the type of cardio that you have a personal preference for. Whichever one fires you up the most because you?ll most likely work harder at it. HIIT is quicker, proves to be more effective for fat loss, creates metabolic changes, and helps with muscle retention but not everybody can do HIIT. LISS is safer, but takes twice as long to accomplish similar things and it still has its place for fat loss in moderate amounts, from a pure calorie burning standpoint (meaning only to burn calories & not make changes to your metabolism). My intentions weren?t to favor one form of cardio and bash the other, even though it sounded like that. My intent was to educate and notify you that times have changed and science is proving some good stuff with HIIT cardio. But at the end of the day it?s up to you on what kind of cardio suits you best.

Hopefully, after reading this article you should have a really good idea of what kind of cardio is right for you and how to effectively use it.




Thanks for the responses, guys.


Instead of say doing cardio and burning 200 cals you could just eat less instead and save yourself hours a week. Then if you get to a point where you dont want to drop your food lower then add it in. Unless ofcourse your at that point already then go with what you think will do the best.

I personally like HIT cardio more because you can be a lot more creative and ofcourse of the nutrient repartitionning benefits which Stu has talked about before


A damn good plan...



This is interesting. My opinion about cardio and a lot of its "muscle-wasting" properties has kind of been altered over the last few years.

I think a lot of it's hype, really.

For instance, right now I'm moving closer to the end of a diet. I've lost about 35 pounds now, and a few days a week I really dive-bomb the fuck out of cardio. Where it has definitely affected how well my legs recover, I'm not really sold on any of my mass really being sacrificed because of it.

I do know that when I do my post-lifting cardio, it's done in a fairly fasted state. I go into the workout MOSTLY fasted (no eating 4-6 hours prior,) and only have a 2 scoop HumaPro shake right before going in. I will go ahead and throw some BCAAs back before I end up doing 20-30 minutes of semi-intense cardio, but IDK.

I am probably thoroughly wrong and will get schooled on this but I feel like this has turned in to one of those "things I can't prove, but believe."


Kind of agree with you about the muscle wasting theory.

I mean a lot of pros advocate fasted steady state while prepping and i bet they don't drop muscle, AAS aside.

If anyone follows Jay cutler on twitter he pretty much does 45 mins on the stair mill everyday.


I am pretty sure walking for 40min or going easy on the elyptical or step mill will not be muscle wasting. It will be good for your health and it will improve recovery. If gaining you need to obviously account for the extra activity and if losing well great more calories you dont have to cut out. But you need that extra 40min to do that.

Personally i get so bored at work I combine my morning break and lunch break and go the gym and just walk for 30-40min and watch some espn. Then do my normal weight session after work. I am positive the walking/low intensity cardio is doing nothing but good things (obviously its not packing on muscle) but it keeps fat down a bit allows for more food...blah blah blah


I think cardio is just used to describe a lot of different things. I bet most people when you say cardio they think of treadmills or just running. I think this led to the whole "cardio will strip all your muscles off!" school of thought. I don't think it would be wise to do repetitive pounding like that throughout the week if your goal was to get truly big. Bit easy walking or elliptical work in a fastest state shouldn't make you go completely catabolic.

I definitely get what you mean by "things I can't prove but believe" statement though.