I did IF for a long while and really didn't notice much of a difference. It's definitely not good for bulking because it's difficult to eat and digest enough protein in an 8 hour window and you want to have enough glycogen in your muscles to support growth. You could do a 14/10 window instead, that a 10 hour feeding window would give enough time for a meal every 2 hours or so.
For cutting, I also don't see the benefit. Cutting happens because of a negative CICO balance. Furthermore, you want to consume extra protein while cutting to prevent the loss of lean muscle.
I found eating carbs not to be a problem while doing IF at all. By default I eat almost all complex carbs though. I don't fuck with candy or white bread and shit like that.
Personally, I think there are other health reasons to do IF. However, fat loss or body composition don't seem to be primary benefits to it. It appears the fat loss outcome for IF is simply because people struggle to eat as much calories in an 8 hour window as they do in a non-restricted eating window.
I am aware IF upregulates various metabolic pathways in the body. I know there are benefits, I just don't know that it is the best way to get results in bodybuilding and certainly not in powerlifting.
Fasting of any kind offers no benefit over a caloric restricted diet. You lost weight because you ate less not some kind of “hack”
Some research suggests that for the same deficit under normal eating window vs an IF schedule, subjects will see greater fat loss with the same deficit+IF. I don't think this is really determined to be true or not yet, the research is still out. Take it with a grain or two of salt.
I will say, I believe this depends on the individual undergoing the intervention. If someone is obese, has diabetes, fatty liver disease, or some other health issues, then fasting
does seem to have the capacity to help the subject, sometimes well beyond that of just calorie restriction/weight loss. The upregulation of AMPK and "cellular cleanup" mechanisms is a HUGE benefit to anyone who is overweight.
My personal approach is to "cycle" fasting. Like I said, I used to do daily 16-8. Honestly, I liked it while I was doing it. I did not notice any drastic benefits, but then again I am already lean. The problem was then I was trying to cram 3000+ calories and 200-250 grams of protein into 8 measly hours. It just wasn't realistic. I might be able to do that now that I work from home, but when I was in an office I couldn't just whip out 5 eggs, spinach, tomatoes, and quinoa and eat in front of everyone LOL.
What really annoys me though is "how hot" IF is right now. It causes all this fucking horrible misinformation to be spread about, basically entirely via social media. People making bullshit videos and blog posts and crap about the benefits of fasting that are based off of someone else's blog post which is based off of someone else's instagram post which is very, very, very loosely based off of like a single study that they interpreted incorrectly and drew incorrect/"reaching" conclusions from. Or someone read a cooky guy's blog like Ben Greenfield and decided to rip off his content and make their own video or podcast episode for clicks and proft. The same goes for the fucking Keto diet, veganism, paleo/ancestral diet, etc., etc..it is just the same bullshit circulating over and over, and the scientifically and health-illiterate public believes it all. /end mini rant
Regardless, I plan to do IF again during this summer. I am in better shape now than the last time I tried it. Probably about 15 lbs more muscle and 8 lbs less fat, so a drastic difference. I'll only do it while doing maintenance diets--not cutting or bulking for the reasons I listed above.
