Is IF gonna sabotage the process of muscle building if the eating window would include the workout so that there are meals both before and after workout?
If you are trying to build muscle, you are probably in a caloric surplus, correct? In which case the fasting should not negatively affect muscle building at all. If you are dieting and trying to retain muscle, it will really depend on the fasting protocol you chosen. The data seem to show that longer fasting periods are worse for lean mass retention. So alternate day or 5/2 fasting is probably worse than the typical 16/8. That is probably somewhat individual and lean mass is not the same as pure muscle tissue, but it’s a good proxy. For the shorter fasting periods, any negative effects seem to be entirely overcome if the workout is within the eating window.
I don’t k ow if you’ll find many good studies on building muscle using IF, as typically IF is used for calorie restriction not intentional over feeding, but here are a couple of good studies where you can draw some outside conclusions:
https://translational-medicine.biomedcentral.com/articles/10.1186/s12967-018-1748-4
https://pubmed.ncbi.nlm.nih.gov/35531785/
https://pubmed.ncbi.nlm.nih.gov/34135111/
https://pubmed.ncbi.nlm.nih.gov/35470974/
https://pubmed.ncbi.nlm.nih.gov/35443107/
As a side note, there have been at least a few proponents of fasting recently say, and probably accurately I think, that regardless of the benefits you experience from IF you’re body will adapt to that pattern of eating and it may be beneficial to have some other eating strategies in your tool box to aid you in reaching your goals. Similar to the way you will probably run multiple training programs with in a year.
Nutritional Practitioner here. Three things. First, we would have to define gains, but I’m assuming you mean putting on muscle mass. Second, what reason are you looking into IF. Third, what is your fasting/feeding window?
If you’re doing a traditional 16/8 fast and eating 2 meals (+snacks) it doesn’t really matter when you eat, as long as your getting your calories in. In general, you require a calorie surplus to put on muscle mass.
The consideration with IF is that you have less opportunity to eat, so you may have to plan your meals to ensure you’re getting adequate calories and protein.
Tldr; if you’re eating enough calories and protein throughout your feeding window, IF should be fine.
I doubt IF in general would severely limit your potential muscular gianz. Studies have shown it can result in just as much fat loss as eating those same cals/protein over several meals throughout the day.
AFAIK there have been no long term studies on comparing muscle built from IF and eating “normally”. I do know that MPS (muscle protein synthesis) can be stimulated maximally up to around 4-5x/day with roughly .25g/lb protein per meal. There’s a ceiling effect to MPS, so taking in more at a given time won’t necessarily be more beneficial. However, while theoretically you may build less muscle on IF, I don’t think it’s been proven. Unless there’s money on the line or whatever then it’s not worth worrying about
No.
Preworkout carbs improve exercise performance.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4042570/
Pre/post workout protein improves quite a few things https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5214805/
All the benefits of IF come from caloric restriction.
So if you are in a bulk IF has no benefit. And if you are in a cut it’s only beneficial if it is easier for you to eat less calories.
I checked out what athletes in weight division sports do to lose weight and maintain muscle mass. This is what I learned:
Insulin antagonizes muscle catabolism by activating the PI3K/Akt/mTOR pathway. Your body secret insulin following a meal. So it’s not just the nutrients but also the endocrine response to a meal that protects muscles. So IF would be a handicap.
Resistance training while waiting for a caloric restriction is one of the best things you can do to protect your muscles. So if you IF, lifting weights is even more NB than cardio.