fasted exercise

TaperPin

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I think it’s all interesting, although it’s all over my head. This thread reminds me of our oldest - one of the fittest humans I’ve ever known and who has the most scientific workouts known to man, that are also over my head. His metabolism is in overdrive all day - and he can eat 4,500 calories every day and not gain a lb.

However, he can’t pull a single weed or mow his lawn if it’s above 80 degrees or he’s covered in sweat and talks like he’s going to die, not to mention he walks around in a 35 year old body that’s as stiff as an 80 year old. A cold weather machine that gets out worked on warm days by his fat old pops. Lol
 

Marbles

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Heat adaptation must be forced. When I was stationed in San Antonio, to acclimate I set my air conditioner to 95 degrees and worked out in the middle of the day. After two weeks it did not bother me, I would also sweat like a pig just walking out the door (sweating before getting over heated is a beneficial adaptation).

Cold is similar, turn the heat down, refuse to wear more than pants and a T-shirt inside. It also comes with annoying things, like hands that get cold very fast as the body clamps down on peripheral circulation before the core gets cold.

I think climate controlled environments do a lot for preventing acclimation. Being a few marbles short also helps with getting some enjoyment from the misery.
 

Loo.wii

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I've read enough research to know it's a good thing (obviously not taken to an extreme) with numerous benefits- increased plasma volume, lower hear rate, increase in VO2 Max- the list goes on. Knowing this and seeing my own results of poor performance in the heat—I still can't get out there and do it.

Maybe I should get a summer job roofing, road flagger or a hot warehouse like you :D
Specifically not eating before you hit the trails has a positive impact on your vo2 max?

Does sucking down gu’s have a meaningful impact?
 
Joined
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Not heat training focused but on the fasted subject, as I get older, I have found I need to ensure I eat lots of protein to keep my fasted workouts from moving me backwards on muscle mass. I now get a protein shake onboard before I lift in the morning. It seems to be helping
 

180ls1

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Not heat training focused but on the fasted subject, as I get older, I have found I need to ensure I eat lots of protein to keep my fasted workouts from moving me backwards on muscle mass. I now get a protein shake onboard before I lift in the morning. It seems to be helping

The body becomes less efficient with protein as it ages so you're on the right track.

Also, workout output when fasted is also lower. While you may burn more fat in the interim, your total output will also be lower so you may actually benefit from exercising in a fed state. Its worth playing around with and seeing what works well for you.
 

P Carter

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I thought I had seen this, and turns out I'm not crazy. Some folks are moving away from advocating fasted workouts. Just posting for everyone's information and consideration. Basically, it looks like the consensus at Uphill Athlete is to move away from recommending fasted workouts, but Scott Johnston seems to still be advocating for it.


Excerpt:

Attention Uphill Athletes: The information in these articles provides outdated, incorrect, and potentially harmful information. Scientific knowledge evolves as new studies are done and we are on the forefront of tracking and keeping you updated on the current best practices. Since this article was published new scientific and experiential findings directly and definitively contradict the information provided in this article. Uphill Athlete’s long-time registered dietician, Rebecca Dent, is working on updating our community on the new best practices, including what the latest research and coaching experience indicates to be best practices, and why. In the meantime, we want you to fuel all of your training sessions appropriately, to make sure you have enough energy to train and recover ready for your next training session and so you can cope with the training load of the week. This will help to ensure you are eating enough energy day to day to support your health and enable you to reach your full fitness potential ultimately helping you achieve your goal of summit success or crossing that finish line. In the meantime, please make sure you adequately fuel your training with a source of carbohydrate.

Note on Scott Johnston. On another website, Mr Johnston, refutes this disclaimer by citing NOW DEBUNKED 10+ year-old studies in an ill-fated attempt to prove that his opinions, which very clearly at odds with modern coaching standards, are still relevant. His views are potentially very harmful. Mr Johnston is 1) Not acknowledging the new research and the evolving process that science is and 2) appears to be unable change his mind when new evidence arises.

Mr. Johnston himself has talked about the problems with overtraining in ultra running. But in the next breath recommends fasted training. Underfueling contributes to health issues related to overtraining. The rest of the coaching community has moved on from the psyeudo-science of fasted training. It is now understood that fasted training, and insufficient fueling in general, can be very harmful and promote under recovery and overtraining and create mulitiple health issues for athletes. Uphill Athlete coaching team and Registered Dieticians have unanimously and enthusiastically moved on from fasted training. We wish to promote healthy training practices based on the well understood principles of endurance training even when (especially when) our understanding of training and recovery evolve.

I also want to add here that I, Steve House, never practiced fasted training in my career as an athlete.
 

IBen

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I've read enough research to know it's a good thing (obviously not taken to an extreme) with numerous benefits- increased plasma volume, lower hear rate, increase in VO2 Max- the list goes on. Knowing this and seeing my own results of poor performance in the heat—I still can't get out there and do it.

Maybe I should get a summer job roofing, road flagger or a hot warehouse like you :D
Funny you mention roofing Thats what I did. Roofing has replaced my training this summer. hottest summer i can remember so far
IMG_3173.jpeg
IMG_4613.jpeg
 
OP
mtwarden

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My buddy had done a lot of roofing before becoming a game warden. When I needed a new roof he said I’ll help you do it and save a ton of $.

The next roof I paid someone to do it :ROFLMAO:
 

1jeds

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Joined
Dec 21, 2021
Messages
82
I thought I had seen this, and turns out I'm not crazy. Some folks are moving away from advocating fasted workouts. Just posting for everyone's information and consideration. Basically, it looks like the consensus at Uphill Athlete is to move away from recommending fasted workouts, but Scott Johnston seems to still be advocating for it.


Excerpt:

Attention Uphill Athletes: The information in these articles provides outdated, incorrect, and potentially harmful information. Scientific knowledge evolves as new studies are done and we are on the forefront of tracking and keeping you updated on the current best practices. Since this article was published new scientific and experiential findings directly and definitively contradict the information provided in this article. Uphill Athlete’s long-time registered dietician, Rebecca Dent, is working on updating our community on the new best practices, including what the latest research and coaching experience indicates to be best practices, and why. In the meantime, we want you to fuel all of your training sessions appropriately, to make sure you have enough energy to train and recover ready for your next training session and so you can cope with the training load of the week. This will help to ensure you are eating enough energy day to day to support your health and enable you to reach your full fitness potential ultimately helping you achieve your goal of summit success or crossing that finish line. In the meantime, please make sure you adequately fuel your training with a source of carbohydrate.

Note on Scott Johnston. On another website, Mr Johnston, refutes this disclaimer by citing NOW DEBUNKED 10+ year-old studies in an ill-fated attempt to prove that his opinions, which very clearly at odds with modern coaching standards, are still relevant. His views are potentially very harmful. Mr Johnston is 1) Not acknowledging the new research and the evolving process that science is and 2) appears to be unable change his mind when new evidence arises.

Mr. Johnston himself has talked about the problems with overtraining in ultra running. But in the next breath recommends fasted training. Underfueling contributes to health issues related to overtraining. The rest of the coaching community has moved on from the psyeudo-science of fasted training. It is now understood that fasted training, and insufficient fueling in general, can be very harmful and promote under recovery and overtraining and create mulitiple health issues for athletes. Uphill Athlete coaching team and Registered Dieticians have unanimously and enthusiastically moved on from fasted training. We wish to promote healthy training practices based on the well understood principles of endurance training even when (especially when) our understanding of training and recovery evolve.

I also want to add here that I, Steve House, never practiced fasted training in my career as an athlete.

Spot on. Our bodies are good at improving metabolic efficiency through exercise alone. Exercise regularly, fuel appropriately. Most people are great at #2 but not #1. There is a reason just about every elite endurance athlete has tremendous fat oxidation rates and still have a very high carb diet.
 
Joined
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Not heat training focused but on the fasted subject, as I get older, I have found I need to ensure I eat lots of protein to keep my fasted workouts from moving me backwards on muscle mass. I now get a protein shake onboard before I lift in the morning. It seems to be helping
This will loop in @P Carter post below, but if retention of muscle is the goal, the best thing to do would be to not workout fasted. In fact, we call carbs "muscle-sparing nutrients" because they literally protect and preserve the muscle from getting utilized as fuel. Whey protein is the fastest-digesting protein we know of, so it makes sense why you'd see better performance after one vs going at it fasted. In fact, we see similar blood sugar rises with a whey shake and white bread. That's not to condemn whey or praise white bread.

The body becomes less efficient with protein as it ages so you're on the right track.

Also, workout output when fasted is also lower. While you may burn more fat in the interim, your total output will also be lower so you may actually benefit from exercising in a fed state. Its worth playing around with and seeing what works well for you.
Great points made on #2!

We don't become less efficient with protein as we age. We do lose muscle at a fairly alarming rate (3-5% per decade after age 30). Adequate protein intake in conjunction with resistance training is the best way to retain muscle mass (in re: to @HighDesertHunter post). In fact, the general consensus seems to be to start as early as possible and then spend the next 30-40 years holding on to as much as you possibly can. We also see that it's never too late to start If you don't have the luxury of a owning a DeLorean or knowing Christopher Lloyd.

I thought I had seen this, and turns out I'm not crazy. Some folks are moving away from advocating fasted workouts. Just posting for everyone's information and consideration. Basically, it looks like the consensus at Uphill Athlete is to move away from recommending fasted workouts, but Scott Johnston seems to still be advocating for it.
The general thing we see in the literature with fasted training is this: you will improve the body's ability to burn fat when fasted, but it also becomes less efficient at utilizing carbohydrate for fuel. Which makes the typical approach of training fasted, but introducing carbs for competition such an irony amongst many "mountain athletes".

What we've found to work best is when mountain athletes train with carbs and slowly increase their capacity to handle MORE carbs in hard efforts. It doesn't just improve performance (it does), but it also spares the muscle to a higher degree...which makes sense since there is plenty of fuel to utilize instead of needing to tap into reserves. Try as hard as we might, the body will still use what's needed if there is insufficient fuel on board (i.e. muscle vs fat). Rate of burning fuel matters too. Fat can work, but it's an extremely slow process that happens from break down to viable fuel source.

Great article and post @P Carter .

@180ls1 nailed it: everyone should play with what works best for them. There's no one size...

There's alot of great conversions going on in the thread here. I love seeing so many folks looking at pieces like this and finding what works for them. We did an episode on fat burning and fasted cardio some time ago if you get curious to hear some other perspectives on it.
 

P Carter

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This will loop in @P Carter post below, but if retention of muscle is the goal, the best thing to do would be to not workout fasted. In fact, we call carbs "muscle-sparing nutrients" because they literally protect and preserve the muscle from getting utilized as fuel. Whey protein is the fastest-digesting protein we know of, so it makes sense why you'd see better performance after one vs going at it fasted. In fact, we see similar blood sugar rises with a whey shake and white bread. That's not to condemn whey or praise white bread.


Great points made on #2!

We don't become less efficient with protein as we age. We do lose muscle at a fairly alarming rate (3-5% per decade after age 30). Adequate protein intake in conjunction with resistance training is the best way to retain muscle mass (in re: to @HighDesertHunter post). In fact, the general consensus seems to be to start as early as possible and then spend the next 30-40 years holding on to as much as you possibly can. We also see that it's never too late to start If you don't have the luxury of a owning a DeLorean or knowing Christopher Lloyd.


The general thing we see in the literature with fasted training is this: you will improve the body's ability to burn fat when fasted, but it also becomes less efficient at utilizing carbohydrate for fuel. Which makes the typical approach of training fasted, but introducing carbs for competition such an irony amongst many "mountain athletes".

What we've found to work best is when mountain athletes train with carbs and slowly increase their capacity to handle MORE carbs in hard efforts. It doesn't just improve performance (it does), but it also spares the muscle to a higher degree...which makes sense since there is plenty of fuel to utilize instead of needing to tap into reserves. Try as hard as we might, the body will still use what's needed if there is insufficient fuel on board (i.e. muscle vs fat). Rate of burning fuel matters too. Fat can work, but it's an extremely slow process that happens from break down to viable fuel source.

Great article and post @P Carter .

@180ls1 nailed it: everyone should play with what works best for them. There's no one size...

There's alot of great conversions going on in the thread here. I love seeing so many folks looking at pieces like this and finding what works for them. We did an episode on fat burning and fasted cardio some time ago if you get curious to hear some other perspectives on it.
No to derail, but I've shifted drastically along these lines. I used to run without fuel for up to 18 miles and think about how much that had improved my ability to operate on fat. (And, of course, think about how "tough" I was.) But in races, I was cramming down swedish fish and gels like there's no tomorrow. So I swapped approaches - I now try to chow down 400 calories/hour on long runs. (Yes, ideally I'd focus on grams of carb per hour rather than calories, but for some reason I find that too annoying to track so I stick with calories. It also enables me to rifle through my kids snacks the night before and pull out the "fuel" for the next morning's long run.)

In all honesty, I'm so slow that I doubt there's any significant impacts on "performance." But after eating 400 cals/hour on long runs, recovery comes much, much faster. I can jump straight into playing with the kids and doing everything else that needs to be done on busy weekends, rather than needing a good period to rest and reset. Which makes consistent training much more achievable.

I'm glad to have done those longer fasted runs, but the opposite approach works much better for the phase of life I'm in.
 
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mtwarden

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My understanding of the best practices for "fasted exercise" was that it should always be in Zone 2 (relatively low output) AND should not exceed much more than two hours.

Soooo... I never thought of this as a race day formula; it isn't even an everyday thing (a person should be mixing in longer duration sessions, higher output sessions, etc). I also never thought about it in conjunction with strength training (which is generally a relatively high output session)—I personally like to be well fueled going into my strength workouts.

My "fasted exercise regime" is simply to get up early and beat the heat, nothing more :D. I'm doing it for two-ish hours tops, mostly in Zone 2 (with maybe a little Zone 3). This "regime" for me only lasts as long as the heat does, which sadly seems to be much longer than normal :(

Someone pointed out earlier in the thread that a good probability that I'm probably already a "fat burner" and not likely to see much of any benefit; but at the same time I'm thinking I'm not detracting from my fitness either :)
 

PVHunter

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This is an interesting thread. The majority of my strength and conditioning workouts are done fasted after water and coffee early in the morning. As with most things, it feels like your body adapts to it over time. If I'm planning to push particularly hard - a heavy leg day looking for a PB or a 2k row time trial - I shift the time of day when I'm working out rather than when I eat.
 

180ls1

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This will loop in @P Carter post below, but if retention of muscle is the goal, the best thing to do would be to not workout fasted. In fact, we call carbs "muscle-sparing nutrients" because they literally protect and preserve the muscle from getting utilized as fuel. Whey protein is the fastest-digesting protein we know of, so it makes sense why you'd see better performance after one vs going at it fasted. In fact, we see similar blood sugar rises with a whey shake and white bread. That's not to condemn whey or praise white bread.


Great points made on #2!

We don't become less efficient with protein as we age. We do lose muscle at a fairly alarming rate (3-5% per decade after age 30). Adequate protein intake in conjunction with resistance training is the best way to retain muscle mass (in re: to @HighDesertHunter post). In fact, the general consensus seems to be to start as early as possible and then spend the next 30-40 years holding on to as much as you possibly can. We also see that it's never too late to start If you don't have the luxury of a owning a DeLorean or knowing Christopher Lloyd.


The general thing we see in the literature with fasted training is this: you will improve the body's ability to burn fat when fasted, but it also becomes less efficient at utilizing carbohydrate for fuel. Which makes the typical approach of training fasted, but introducing carbs for competition such an irony amongst many "mountain athletes".

What we've found to work best is when mountain athletes train with carbs and slowly increase their capacity to handle MORE carbs in hard efforts. It doesn't just improve performance (it does), but it also spares the muscle to a higher degree...which makes sense since there is plenty of fuel to utilize instead of needing to tap into reserves. Try as hard as we might, the body will still use what's needed if there is insufficient fuel on board (i.e. muscle vs fat). Rate of burning fuel matters too. Fat can work, but it's an extremely slow process that happens from break down to viable fuel source.

Great article and post @P Carter .

@180ls1 nailed it: everyone should play with what works best for them. There's no one size...

There's alot of great conversions going on in the thread here. I love seeing so many folks looking at pieces like this and finding what works for them. We did an episode on fat burning and fasted cardio some time ago if you get curious to hear some other perspectives on it.

This is what I was referring to with the protein intake.


Elderly adults are less responsive to the anabolic stimulus of low doses of amino acid intake compared to younger adults [18]. However, this lack of responsiveness in elderly adults can be overcome with higher levels of protein consumption [18]. This is also reflected in studies comparing varying levels of protein intake [19]. This suggests that the lack of muscle responsiveness to lower doses of protein in older adults can be overcome with a higher level of protein intake. The requirement for a larger dose of protein to generate responses in elderly adults similar to the responses in younger adults provides the support for a beneficial effect of increased protein in elderly populations [8]. The consumption of dietary protein consistent with the upper end of the AMDRs (as much as 30%–35% of total caloric intake) may prove to be beneficial, although practical limitations may make this level of dietary protein intake difficult. The consumption of high-quality proteins that are easily digestible and contain a high proportion of EAAs lessens the urgency of consuming diets with an extremely high protein content.
 

Stickmark

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I have done some backpacking on lighter rations, like apples and avocados, and did alright. The body can adapt. Last summer, walked out of the GIla, along the river, only with coffee and a protein packet mixed w water; 9.5, 10 miles after a grueling backpack, and while certainly hungry at times, also certainly doable.
Weights is doable on a 12, 14, 18, 24hr fast, but I see an issue with performance after that 24hrs in the gym.
 
Joined
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Totally believeable. I suppose like anything it's ballpark information. Mine actually malfunctioned and the light intensity burned my wrist. It blistered before I took it off. Felt like a shock at first.

And here I am wearing one still.
I had the same thing happen and yes, I'm still wearing it. All involved should get a HRM chest strap setup as it is the most accurate. My watch was giving me info that said I wasn't working hard at all (low zone 2). Once I got the chest strap, it said I was exercising in zone 4. That's how off the watches can be.
 

Marbles

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I thought I had seen this, and turns out I'm not crazy. Some folks are moving away from advocating fasted workouts. Just posting for everyone's information and consideration. Basically, it looks like the consensus at Uphill Athlete is to move away from recommending fasted workouts, but Scott Johnston seems to still be advocating for it.


Excerpt:

Attention Uphill Athletes: The information in these articles provides outdated, incorrect, and potentially harmful information. Scientific knowledge evolves as new studies are done and we are on the forefront of tracking and keeping you updated on the current best practices. Since this article was published new scientific and experiential findings directly and definitively contradict the information provided in this article. Uphill Athlete’s long-time registered dietician, Rebecca Dent, is working on updating our community on the new best practices, including what the latest research and coaching experience indicates to be best practices, and why. In the meantime, we want you to fuel all of your training sessions appropriately, to make sure you have enough energy to train and recover ready for your next training session and so you can cope with the training load of the week. This will help to ensure you are eating enough energy day to day to support your health and enable you to reach your full fitness potential ultimately helping you achieve your goal of summit success or crossing that finish line. In the meantime, please make sure you adequately fuel your training with a source of carbohydrate.

Note on Scott Johnston. On another website, Mr Johnston, refutes this disclaimer by citing NOW DEBUNKED 10+ year-old studies in an ill-fated attempt to prove that his opinions, which very clearly at odds with modern coaching standards, are still relevant. His views are potentially very harmful. Mr Johnston is 1) Not acknowledging the new research and the evolving process that science is and 2) appears to be unable change his mind when new evidence arises.

Mr. Johnston himself has talked about the problems with overtraining in ultra running. But in the next breath recommends fasted training. Underfueling contributes to health issues related to overtraining. The rest of the coaching community has moved on from the psyeudo-science of fasted training. It is now understood that fasted training, and insufficient fueling in general, can be very harmful and promote under recovery and overtraining and create mulitiple health issues for athletes. Uphill Athlete coaching team and Registered Dieticians have unanimously and enthusiastically moved on from fasted training. We wish to promote healthy training practices based on the well understood principles of endurance training even when (especially when) our understanding of training and recovery evolve.

I also want to add here that I, Steve House, never practiced fasted training in my career as an athlete.
This is Scott's answer to that.

What he is saying makes sense, and modifies the definition I had of fasted training. By what he says, I have been doing it wrong. Without outcomes driven research, one must be humble about what they conclude from intermediate markers. Bodies are complex. That said, I'm going to pay more attention to food on long duration output sessions (and continue eating immediately after training).
 
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