Intermittent Fasting and Morning Workouts?

Triathlon Forum
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I am trying intermittent fasting for the offseason. No reason other than something to test since I am borderline mental about nutrition/calories.

I am trying the 16:8 fasting schedule. Been doing it for 5 days and it is working pretty good. But, I am getting exhausted in my morning swims. Luckily, I have always ran in a fasted state when training. I just always ran before breakfast.

But now, I am eating at 7pm, then not working out until 8am and I just dont have the energy. No way I could do a two hour bike ride.

For those of you who do 16:8 and workout in the morning, how do you get through your workouts?

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folowing
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Are you allowing yourself coffee before your morning workout? I know there is some research to suggest coffee can kick you out of a fasted state but not sure if you are taking it to that extreme. I ask because I train almost exclusively in a fasted state and find a good cup of coffee does the trick. I bring the coffee pool side and sip during rest periods.

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I did it for a long time before I started training, and always felt great. It was also a pretty easy way to get very lean.

There’s no way I could do it while training, though, and neither do I particularly see the point of doing it.

If you feel good and strong training fasted and it doesn’t impact you recover, great. But if not, what’s the point? At least for me, triathlon is about performance and not aesthetics. Lots of easier ways to diet than endurance training on limited calories (at least for me).

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I am trying intermittent fasting for the offseason. No reason other than something to test since I am borderline mental about nutrition/calories.

I am trying the 16:8 fasting schedule. Been doing it for 5 days and it is working pretty good. But, I am getting exhausted in my morning swims. Luckily, I have always ran in a fasted state when training. I just always ran before breakfast.

But now, I am eating at 7pm, then not working out until 8am and I just dont have the energy. No way I could do a two hour bike ride.

For those of you who do 16:8 and workout in the morning, how do you get through your workouts?

Most I do is 16 hours fasted once a week .

I have no trouble getting thorugh the first workout of the day, but if I bike fasted, then eat, and try to swim at lunch, I’m wasted. I’m pretty much ready to concede that I’ll only be working out once the day I come off the fast. I don’t think there is any way I could do 16:8 daily.

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I have been doing the 8/16 IF for a couple months now. for me, it got easier over time and realized I was over eating carbs by quite a bit before. but I just have coffee with some mct oil powder before I ride and amino acid mix in my water bottle on the bike and can go for a couple hours without thinking about eating.

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I do a 10 hour eating window each day. Took me two solid weeks to get used to hard trainer rides but you eventually are able to do it.

One thing to point out is that you only need to do it 5 days per week to get all the benefits. Caffeine / anything that affects your metabolism kicks you out of fasted state. Also, the goal is a reduced eating window, not reduced eating, so make sure you still have the same number of calories each day, just consumed in a shorter period of time.

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I do a 10 hour eating window each day. Took me two solid weeks to get used to hard trainer rides but you eventually are able to do it.

One thing to point out is that you only need to do it 5 days per week to get all the benefits. Caffeine / anything that affects your metabolism kicks you out of fasted state. Also, the goal is a reduced eating window, not reduced eating, so make sure you still have the same number of calories each day, just consumed in a shorter period of time.

Everything I have watched and read says black coffee is ok. I sip one a 16 oz coffee all through out the first half of the day.

My runs are fine fasted, although I have not tried speedwork or intervals. But my swim time is down from 2:04/100yds to 2:07/100yds over a 2500yard set. I went from horribly slow to even more horribly slow.

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Dr. Rhonda Patrick cites studies showing that caffeine will kick you out of fasting.

https://youtu.be/uxM_CLsvieE?t=2h34m32s

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I am trying intermittent fasting for the offseason. No reason other than something to test since I am borderline mental about nutrition/calories.

I am trying the 16:8 fasting schedule. Been doing it for 5 days and it is working pretty good. But, I am getting exhausted in my morning swims. Luckily, I have always ran in a fasted state when training. I just always ran before breakfast.

But now, I am eating at 7pm, then not working out until 8am and I just dont have the energy. No way I could do a two hour bike ride.

For those of you who do 16:8 and workout in the morning, how do you get through your workouts?

I do 16:8, 3 or 4 days a week. I just plan my high intensity training around the unrestricted eating days when I can.

Over all though I would say you just get used to it. I do tend to eat a much higher % of fat in my diet and I’m not very hungry outside of the feeding window. I do have coffee in the AM with heavy cream.

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Dr. Rhonda Patrick cites studies showing that caffeine will kick you out of fasting.

https://youtu.be/uxM_CLsvieE?t=2h34m32s

Neither watched the video nor a nutrition expert so I‘m happy to be corrected:
From my understanding our human body constantly metabolises fat out of our adipose tissue during a fasted state (fasted state can also be ca. 2 hours(?) after a meal until your next). The caffeine triggers/increases the effect of lipids breakdown (wikipedia:
Caffeine is metabolized in the liver by the cytochrome P450 oxidase enzyme system, in particular, by the CYP1A2 isozyme, into three dimethylxanthines, each of which has its own effects on the body:

Paraxanthine (84%): Increases lipolysis, leading to elevated glycerol and free fatty acid levels in blood plasma.

Lipolysis /lɪˈpɒlɪsɪs/ is the breakdown of lipids and involves hydrolysis of triglycerides into glycerol and free fatty acids. Predominantly occurring in adipose tissue, lipolysis is used to mobilize stored energy during fasting or exercise. )

The delta between normal fat metabolism during fasted states vs. caffeine induced fat metabolism during fasted state could be defined as a break of fasting?

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The delta between normal fat metabolism during fasted states vs. caffeine induced fat metabolism during fasted state could be defined as a break of fasting? ///

Glad to see this older thread, as I missed it the first time. And apparently since there there have been many other threads on this topic, even in the lavender room!! I’m coming up on 5 months of 18 to 23 hours a day of IF, only on black coffee, and I train every day fasted for up to 1 hour 45. I don’t know what the effect of the coffee has, but to me it is essential to just have something while the whole family eats around me, and I just love coffee. I have seen people say both things, it breaks the fast, it does not break the fast, so not sure anyone knows for sure, but one side is right.

But really, I’m not trying to get to ketosis or anything like that, but to lose some weight, burn fat better and more efficiently, and overall health. SO far I have hit all those goals, and before and after blood tests confirm that just a couple months made significant changes. This week I hit a 20 year low on weight, just chipping a couple tenths here and there, but trend has been down since I started. Guessing that it is body fat being lost too, take pains not to be dehydrated, and take salt caps in the morning to get through my workouts…

And as to workouts, I did a super hard hour swim yesterday, and felt great at the end and could have kept going. Once of these days when I have ridden more, it would be a fun experiment to see if I could ride 2 to 3 hours and still feel great. I have done 2 races in this time and broke the fast, but honestly I did not feel as good in them as I do daily in my workouts, but just too afraid to go race fasted. But I’m leaning towards that experiment one day…

Good stuff folks, seems like most are having very positive experiences. I have 3 friends who also started this, and all love it too. Now thinking about SH’s multi day fast over the the LR, that could be the next big experiment…

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I found that with 16:8 it really worked for my body composition

However my appetite decreased as well (perhaps stomach shrinking?)

Great for fat loss but I wasn’t eating enough during my eating window and my morning workouts would suffer. Once I realized this and ate more (carbs particularly) everything was better and I maintained my weight

So my suggestion would be, don’t change anything and eat more during your eating period

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I intermittent fast everyday, it’s called sleeping.

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**I intermittent fast everyday, it’s called sleeping. **

SO we can put you down for a 14 hour eating window, thanks for that input, very helpful…

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I’m in the same boat as several people here and agree with some of the comments (have been fasting 16 hours, give or take, several days a week, early morning workouts with some intensity are not a problem, I rarely go over an hour in the morning though).

What I wanted to comment on is racing in a fasted state. I haven’t done it. But over the last month or so I’ve done two races (a sprint tri and a 5K - staple distances that I do often). In both, I ate less than my usual breakfast in the past - I only had some coffee and a light granola bar. This wasn’t so much intentional as it was because I was in a rush.

In both I felt awful and was slower than usual. For the 5K I was able to do a proper warm up, but not for the tri. I thought initially that the warm up was the culprit, or maybe I’m losing fitness with age (just turned 48). But I’m also wondering if lack of calories at beginning of race were a factor. I have some other races in the next few weeks and I’ll make it a point to have a proper breakfast and see how it goes.

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I tired this for a few months. 16:8. it just didn’t work for me. I lost some weight but my workouts suffered. I ended up going back to eating when I wanted and with the improved performance in my workouts I found that made up for the hours I lost not eating while fasting and lost weight more rapidly without the fast. I will say if you follow what I would call is my normal eating hours I really do not eat breakfast till around 10AM and I try to not eat after 9. which is an 11 hour eating window. I just do not see the significance for myself of restraining from eating an additional three hours when it caused my workouts to suffer. The fasting itself was not difficult mostly the motivation for and during workouts suffered in my experience.

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But I’m also wondering if lack of calories at beginning of race were a factor. I have some other races in the next few weeks and I’ll make it a point to have a proper breakfast and see how it goes. //

That is how I felt in my races too, but I had the opposite thought that it was not calories, but that I was interrupting my routine by eating. I feel so great virtually everyday in training, so I’m not sure more calories is my answer. Of course my longest race was about an hour, so a time I do everyday fasted without incident. For sure if I were to go 1 1/2 to 2+ I would eat. Let me know how it goes for you, maybe what I eat or when is also the problem, or like you say, just being an old man without the fitness to go as fast as my brain wants to!!!

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I have tried 16/8 and found it quite effective. However, i have started training in the morning (mostly running) before work and, while doing 16/8, I only ate during a 13:00 to 21:00 window. Would it be detrimental if i ran in the morning and didn’t break my fast till 13:00? I do not really want to lose any muscle mass and have always read that you should refuel as quickly as possible after a workout.

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But really, I’m not trying to get to ketosis or anything like that, but to lose some weight, burn fat better and more efficiently, and overall health. SO far I have hit all those goals, and before and after blood tests confirm that just a couple months made significant changes.

Same boat here. I don‘t want to get into ketosis nor do I do some relegious definitoon on fasting. Just would liketo use the off season to get my fat metabolism improved, shed some body fat while focusing on strength training before I go back to structured triathlon training.

I‘m on 18/6 with an eating window between noon and 6 pm. In the 18 hours I like to have my body storages to contribute to my energy expenditure.