I’ve heard that fasted cardio (ie. Cardio performed first thing in the morning on an empty stomach) is better for losing fat than regular cardio in the gym.
My normal routine is to go to the gym at about 6pm and do about 45 minutes on the exercise bike. Would I lose more fat if, instead, I did that 45 minutes first thing in the morning on an empty stomach? Or does it not make any difference?
Cheers.
I’ve never heard of fasted cardio, but burning calories is burning calories no matter what time of day you do it. I vote for it doesn’t matter.
The problem is you don’t “burn calories” you burn parts of your body. One of the things that happens when you sleep is that your body moves to metabolic pathways that favor fat AND protein burning as opposed to the pathways that favor carbohydrate burning, so in the short run, you will TEND to burn more fat and protein if you do your cardio in the morning. If you’d like to also retain your muscle, eating protein immediately after your morning workout will help.
But this is all just worrying about the icing on the cake rather than focusing on the bigger picture.
What matters a million times more than when you exercise is HOW you exercise. If your 45 mins of cardio isn’t high intensity interval training, you’re getting far less benefit from your workouts than you could. The goal of your training shouldn’t be to burn calories at the gym, the goal of your training should be to ramp up your metabolism so you burn more calories all day long and high intensity interval training does just that.
Al this stuff about “low intensity exercise favors fat burning” is true, but it’s short sighted. Your body naturally shifts through different metabolic pathways in your 24 hr cycle and by using HIIT to ramp up your metabolism, you will burn more fat as you sleep and rest and since you spend way more time sleeping and resting than you do in the gym, it’s by far the best tradeoff.
I should have mentioned in my OP that for medical reasons that HIIT is out of the question for me. I can either do fasted low intensity cardio in the mornings or regular low intensity cardio after work as I’m doing at the moment. I take it from your post that fasted cardio is the better of the two options.
It doesn’t make any difference. From “Body composition changes associated with fasted versus non-fasted aerobic exercise” by Schoenfeld, et al, 2014 (cite)
DinoR nice cite.
That said I’d be cautious about generalizing from that one study of 20 young healthy females with an average BMI of 23 at the start divided into two groups of 10 to females who have more fat mass or males of any BMI.
Which isn’t to say anything one way or the other on answering the question.
It is established (see discussion in the intro of your link for a few of the cites) that aerobic exercising while fasted increases the ability to utilize fat for fuel during aerobic exercise (which does not necessarily mean total fat loss over the day but may be meaningful when training for an endurance event). Of course exercising while fasted also decreases the ability and tendency to exercise as hard or as long, which is probably more important.
I don’t think there is GQ level answer based on what is currently known. My guess is that it doesn’t matter much one way or the other.
I have always heard that excersizes that increase muscle mass are the most effective for weight loss because muscle increases the amount of calories we burn each day.
What works best is what you most enjoy. The small gains, if any, of working out first thing it the morning won’t matter if you’re so tired that you quit after a week. For me, morning workouts don’t happen because I’m too tired and they make me tired all day.
If you’re already at the gym, see if they have any spin classes. These are cycling classes that you do in a group setting under the guidance of an instructor. I find I’m much more motivated and work out harder in the class than if I just rode a bike on my own. On my own, after 15 minutes I’m looking for excuses to stop. But in the class, the hour goes by and I’ve hardly noticed it. You can easily lose 600-800 calories in the spin class.
For 45 minutes of exercise, it probably doesn’t make all that much difference. I’ve gotten out of bed and gone on a 3 hour bicycle rides without eating in a stupid attempt to ‘train my body to use fat’. Towards the end of the rides I’d be about 5 mph slower than normal and feeling like crap. I was closing in on what is known as ‘bonk’. I also felt bad the rest of the day and don’t feel much like riding the next day.
On the other hand if I eat or drink some sports drinks, I can ride much better, or even longer, plus feel much better the rest of the day. I probably burn a lot more calories, even more than than I consumed.
My early morning workouts are twice a week (I do after work fitness classes the other days.) I do Body Pump Friday mornings at 5:30a and Saturdays I do HIIT followed by Body Pump. I have found a few teaspoons of peanut butter before the morning work outs help me tremendously. One day I did HIIT/Body Pump, came home, ate a sandwich, and ran out to do errands. When I came home I was shaky and dizzy and had to lay down. Ivylad ran out to get me a Powerade, but I wasn’t 100% until the next morning.
Since that day, I’ve grabbed a smoothie at they gym after my Saturday workouts and I’ve had faster recovery.
Here’s one theory behind the idea:
X* hours after eating, the easily burned sugars in the your body are depleted and your liver starts digging into its reserves. Eventually fat is broken down and that starts getting burned.
By exercising at the end of your longest daily fast time (e.g., before breakfast) at this point your body is going to be burning off fat more quickly than at any other time.
Note that there is also the compounding idea that Y minutes into cardio exercise, the above also starts to happen. So a fasting routine, in theory, lowers your “Y” considerably. I.e., you might starting burning fat quite quickly in your routine.
So, the notion that calories are calories and it doesn’t matter when you exercise is quite obviously naive (and it’s sad that people have already posted this knee jerk reaction). OTOH, the above theory is not exactly proven and might in fact be wrong. Nonetheless, simple criticism of it isn’t worthwhile.
This thread inspired another question of my own. Which is better for weight loss-- a 20 min run on the elliptical or a 40 minute jog on the elliptical? I know the 20 min gets your heart rate up higher, but I see that i’ve burned more calories after the 40 minutes. Which will be better for me in the long run? Thanks.
How are you measuring the calories burned. Is it from the exercise equipment? I do not think that these are very accurate. They are just doing a very simple calculation using heart rate and possible weight to come up with the calories burned.
Burning calories is generally better for weight loss, so if you can spend a longer time at an activity you’ll lose more weight. There are benefits from higher intensity exercise, but weight loss isn’t a major benefit.
The higher intensity is better.
You want your body to change. You want your body to improve. What causes that? Adaptation to a stimulus. “Stimulus” in this case meaning “pushing the boundaries of what I’m currently capable of”. Doing the same thing every day will not improve your body at all. Doing something “easy” will not improve your body at all. The caloric deficit will help shrink your body, which is a good thing if you’re obese, but it will not improve your body’s capabilities.
Think of it this way: Doing the same routine every day is like putting your money in a shoebox. It’s good that you spend less than you earn, and accumulating money is a good thing. But what we’d ideally like is a positive rate of return. And money in a shoebox earns 0% interest. But the repeated application of big stimuli (heavy weights or high intensity cardio*) is an investment. Your body will improve, making it possible for the next stimulus to be larger (heavier weights or higher intensity). Which makes it possible for you to be more active, more capable, and ultimately healthier.
“Exercise” is what we call those easy, same-thing-every-day, calorie burning routines. The intelligent application of the stress-recovery-adaptation cycle is called “training”, which requires having a longer term plan than just “burn some calories every day”. The exerciser just wants to be active for an hour or so. The trainee knows what his goal is today, next week, and next month, and has a detailed plan to get there.
Training provides a positive feedback loop that is simply not possible with exercise by itself. This is the main reason people can lose 30, 40 pounds and then just hit a wall where they can’t lose any more. Their bodies have not improved, and the caloric deficit just isn’t possible anymore without having more strength, higher cardio-respiratory capacity, and more energy. Invest in training, it’s worth it.
*“Repeated application of stimulus” here means that intensity has to increase each time. You’ve already adapted to last week’s workout, now you need a larger stimulus to continue to drive the adaptation. (It’s more complicated than that, actually – you can increase intensity OR volume, and eventually you won’t be able to recover between workouts so you’ll have to include some non-stimulating “easy days” to help with recovery).
Thanks for all the responses, gazpacho and Telemark. DrCube, yours was very helpful, thank you very much for your input. I am inspired to get back to becoming the healthy person I was meant to be!
Dave