I ask because I wonder about the effects of extended fasts on muscle loss/retention, a big problem cutting weight for some people is that they get rid of some muscle mass along with the calories they wanted to eliminate.
About a year ago, I increased my activity level significantly (distance running, hiking, strength training, cycling) and quickly found that:
a) I wasn't recovering quickly enough
b) It was extremely difficult to take in enough calories for a day in a single meal
c) I had very low energy when in ketosis
Eventually I gave up and just started eating on a typical 3-4 meal a day schedule. My RMR steadily increased back to baseline, I got a lot more explosive energy, my body began responding much more rapidly to training, and my recovery speed improved significantly.
Personally I think that intermittent fasting is not a good idea if you are very physically active. That's just my opinion from my own experience.
Did you experiment with any other patterns?
Don't be thrown off by the title. Yes, one group received testosterone, but even the placebo group that did not receive anabolic steroids, lost nearly 10 pounds of fat without losing any appreciable amount of lean body mass.
Dr. Peter Attia wrote about it in his newsletter this past week. [1]
Between my anecdotal experience of not feeling like I lose much lean body mass while fasting, this study above, and recent evidence from studies shown that "muscle memory", where a muscle can quickly regain any lost size it has had, is in fact real...I don't lose much sleep over losing muscle while fasting.
[0] https://www.sciencedirect.com/science/article/pii/S235239641... [1] https://peterattiamd.com/can-you-preserve-lean-body-mass-dur...
Nope.
I stopped counting macros and started eating just whatever again at the beginning of the summer and I'm slowly gaining the fat back. Unfortunately, there are no shortcuts (at least for me).
If you're focused on BF%, lifting is even more appealing since you'll be building muscle/reducing bf% even at a constant weight.
It sucked, it was hard (especially on a caloric deficit), but it worked.
So what happens? You lose muscle and fat in the same ratio? Or do you keep the fat?
There are people that literally just start skipping breakfast while keeping lunch/dinner/snacking the same. This is both technically intermittent fasting but also a reduction in overall caloric consumption. These people sometimes attribute their newfound weightloss to IF, when really they just started skipping a calorically dense meal every day.
For the past year, as an experiment, I've eaten carbs "normally" while doing 4x week gym. Few things I've noticed. My gut doesn't feel as good as it did while keto/IF, when you are in Keto and eat a cup of oatmeal ~45min before gym and start lifting you have this insane focus for the heavy 1-3 reps, I can seem to tolerate more better quality volume now compared to while doing keto/IF. But the overall feeling I have outside of the gym while not being in Keto/IF is a bit "sad", so most likely I'll start doing Keto/IF again to feel better. It's funny how insanely sweet strawberries taste while in Keto, and I kinda miss that feeling.
I personally found very hard already to progress on weightlifting during diet cycles, as I need to cut on volume significantly; can't imagine to do that while fasting, unless fasting would "flip a switch" in how the (my) body works, which I doubt.
Allow me to step right up.
First, as you might expect, aerobic and endurance exercise benefits greatly from being in a fasted (16-24 hr) state. You're light, quick and your body is devoting zero blood flow (and other resources) to digestion. I suspect you're not surprised by this.
Second, I do a 1.5 hour heavy leg workout which includes squats, deadlifts and other assorted "big" movements with weight that is significant, compared to my body weight. No issues at all. I wouldn't do this on a 24 hour fast, but it is my regular habit to do this workout while in a 16-18 hour fasted state and in general I have very slightly better results than if I had eaten recently. Again, the issue is the amount of blood flow (and other resources) your body is putting into digestion.
Finally, while it is easy and enjoyable to do my BJJ workouts in a fasted state, I cannot, then, do several rounds of sparring at the end without more recent calories. Or rather, I can but I after round one or two I am running out of gas.
YMMV. You should just try it. It costs nothing.
If that's true, why isn't it a universal practice in amateur and professional athletic competition?
(Or, for that matter, why isn't it banned?)
When you are right at the edge of your abilities being just a couple pounds lighter can feel like a world of difference (people hone down their rack to precisely what they need for a route, nothing more), especially on sport and boulder problems. My anecdata points to it being great for the project/performative aspects of the sport but as a tool for consistent progression/improvement, I am less confident in stating anything.
I'd say it depends greatly on the effort and the individual. Long, slow distance for someone who is accustomed to training fasted? Fat stores will suffice as an energy source.
But add in some intensity and that's gonna be rough without much glycogen in the tank - which will be the case if you've been fasting for the past 16-24 hours.
First, fasting does not require that your overall calorie intake is reduced. If your cut-goal is 2000kcal per day, you can fast in the morning and eat all 2000kcal in the afternoon. Ultimately, I find this is actually an easier and less hunger-inducing way to each your cutting goals.
Second, you're right. Doing weightlifting while fasted is hard. It's better to coordinate your gym schedule with your eating schedule so that you can eat -- I like a simple protein shake -- before and after the gym.
Third, I'm seeing a lot of folks talking about intermittent fasting ("IF") and day-long fasting in the same breath. I think IF is great for weightlifters on a cut diet. But I think day-long or multi-day fasts are different and should only be done occasionally (weekly being the most frequent) if you are trying to progress with weightlifting. YMMV.
The studies may not have been conducted among athletes so, testing your own body's response (by measuring lean body mass before and after a fast) seems like the best way forward.
I have read that people on keto diets or fasting have less "explosive" energy for workouts. I am not concerned that my body is going to cannibalise my biceps if I don't eat for a day or two. There is a lot more energy kicking around that is less important.
For me, it's worth it for the HGH boost: https://www.dietdoctor.com/fasting-and-growth-hormone
Gist of it is you still cut significant calories only eating like 500-800 a day in mostly low fat protien rich foods. Targeting only enough protien to avoid muscle wasting.
While I'm no doctor or nutritionist, my understanding is that it's for that case, you want some of the benefits of fasting like going into ketosis while maintaining lean mass.
Unfortunately I'm on my phone only this week so I can't try and find any studies about it, but I came across it first in connection with type 2 Diabetes. So you might have some luck googling those topics for more info.
I am inside all day and get no sun - Vitamin D
I do not eat wild caught fish - Omega 3s
I am vegan - B12
I do not eat greens daily - Multivitamin + Magnesium Theronate/Glycinate
I have done some fasting recently (water, some water/apple cider vinegar in the morning; coffee, green tea, Ooolong tea), and have a similar vitamin intake (B complex; calcium/D combo; Magnesium; Zinc; Iron; Fish Oil).
During the fasting I don't take the Fish Oil, I haven't read anything about it specifically, but just assumed Fish Oil was fat that would break the fast. Do you have an opinion on that? I'm Guessing the caloric intake (if any, I am not even sure) is not enough to trigger metabolic response, and as a fat wouldn't trigger insulin response.
I literally cannot get enough Vitamin D in the winter: The days are short here in Norway and the sun isn't enough. Theoretically, I might be able to get it in the summer, but I really need to wear strong sunscreen since a medicine increases my skin cancer risk. The neurologist doesn't really want me to not take the supplements anyway.
My diet isn't bad. Mostly vegetarian, though I try to eat fish once a week and not otherwise completely devoid of animal products (dairy, for example). The rest of my bloodwork turns out OK.
Anecdotally, I can tell you that historically I used to get sick 2-3 times a year minimum, and since I began taking vitamins 5 years ago I got sick 1 time.
But I do generally agree with you about vitamins and minerals coming from diet over supplements, but I also say if you can get all your vitamins and minerals from food, your just not running enough (thats a joke).
A fish oil pill has around 14 calories and most of the times will break your fast -> Take it after your first meal.
Vitamin D is a fat soluble vitamin and you should take it only after a meal containing some fat. Taking it while fasting will just not be absorbed.
I settled on this pattern years ago before I heard anything about it. It just seems right and natural for my body. I've never been into snacking and breakfast would make me feel ill most days (coffee gets a pass) so that naturally means I don't eat before lunch.
Though I wonder how much of that is our modern lifestyle. If I go to the gym early or do something physical, then I'll get hungry and actually want food. Usually I try to go to the gym around 10am or later, which I do without any food in my system and I feel fine. I'm not trying to gain mass though.
As an aside, a meal consisting of just this isn't very balanced. There is effectively 0 fats in it. Egg yolks are actually quite healthy and would have rounded this meal off nicely
[1] https://www.womenshealthmag.com/uk/food/healthy-eating/a7053...
Do you have a citation for the "starvation mode" ? If it's the 1940's study from MN, that was only when the subjects where well into single digit fat %.
So, for example, you don't click from building muscle to consuming muscle. What happens is that catabolism has a higher flow than anabolism, so the net balance is negative.
As the body becomes leaner in starvation conditions, processes that recover energy from gluconeogenesis or from lipolysis cannot produce "enough" energy. So feedback loops that suppress the breakdown of organ tissue weaken and eventually that loop shifts.
* "independent processes" is better described as "interdependent, oftentimes antagonistic processes".
* In describing net balance, the key is that both processes remain active throughout, even if only the net balance of flow can be observed. Or more likely, the integration of the net flow over time (the stock).
* I say "that loop shifts", more accurately the loop dominance shifts. This is a term from system dynamics for describing how the behaviour of the overall system can suddenly change due to a change in flow of one or more loops that are working antagonistically.
Most people are not "fat adapted" meaning their body/brain primarily run off of glucose.
When you fast and your body runs off of glucose, it still goes into ketosis and burns fat, but the brain still needs glucose because that its accustomed primary fuel source (think of marathon runners hitting the wall, that is their body conserving remaining glucose in the body for the brain to function). When their is no dietary glucose the body breaks down protein (muscle and organs) to convert into glucose to keep the brain working (gluconeogenesis).
This will still occur but to a far lesser degree to people who are fat adapted and primarily use fat for energy.
When doing bodybuilding (or sports in general), one can very easily measure their own bodyfat, and losing more muscle than fat is the enemy #1 during diet cycles (whose objective in fact is to minimize muscle loss and maximize fat loss).
Of course, "plenty of adipose stores" is relative. I guess that if one is 30% BF and never does any activity, as soon as they start to lift some weights, they'll put muscles and lose fat quickly for some time, independently of the calories deficit.
The other exception is when one takes anabolic steroids.
In healthier rats, protein turnover (cannibalizing muscles / organs) was faster than in obese rats. I had some human studies bookmarked, I'll try to find them again. There were a few ketosis studies that discussed "starvation mode" so maybe try searching for that.
Please do. Rat studies are helpful, but not definitive-- close but not exact. That's why it takes so long for medicines and therapies that are shown to absolutely work on rats still take forever to reach humans.
I welcome any opportunity to point to almond butter as an extremely dense, and healthy, source of calories.
Easy to add to a smoothie.
Speaking more broadly, I would have a hard time with IF, etc., were it not for shifting about 20-30% of my calorie input to nuts, generally. Mostly raw in form.
I wouldn't do that. Nuts contain tons of metals that you don't want to overdose on.
Perhaps you are speaking of conventional (non organic) nuts and seeds ? I would not consider consuming those.
[1] https://www.cabdirect.org/cabdirect/abstract/20183271188
Your link is broken btw.
https://www.researchgate.net/publication/325951651_Determina...
- Fasting > 24 hrs paradoxically gives you an extreme boost of energy and mental focus. I especially love how my olfactory sense is extremely heightened. It's pretty cool and even after all these years doesn't get old.
- Fasting is not a panacea. Depriving yourself of nutrients or eating garbage is still a bad idea even if you fast or do IF. Unfortunately, eating healthy is hard and kinda' sucks. Egg whites and chicken + broccoli gets old pretty fast.
- Fasting >7 days is a bad idea unless you know what you're doing. This is when your muscles and vital organs start contributing as an energy source (e.g. they also start breaking down).
- Your body is clever, so extended fasts will start putting you into "starvation mode" and you'll lose some of the benefits.
- There have been NO STUDIES on long-term fasting (e.g. over the course of an adult lifetime). This is a big warning sign to just be careful and not overdo it. Different people have different tolerances. Talk to your doctor.
- Even on fast days, make sure you take vitamins (I take Fish Oil, Zinc, a Multivitamin and Magnesium)