On Robb Wolf's podcast a couple weeks ago they answered a question of mine about whether it made sense to take BCAAs before and after fasted training if your goal is fat loss. Rob said that BCAAs will definitely help because the last thing you want when trying to lose fat is to lose lean muscle mass. It seems like this would apply to your situation as well. Believe me, you won't bulk up doing weight training if you are in a calorie deficit, but you do want to be careful not to lose the muscle you have by starving it after a workout.

For normal people with a health & longevity outlook: eat paleo and exercise. As to all the details of exactly how often you eat, postworkout nutrition, etc: irrelevant. Just get a system going that works in the context of your life, and enjoy. You're doing great!

Even in the realm of exercise, Robb's first principle is "do what you love".

What you're doing is very good for you - you're starting autophagy, which will extend your life, you're also resetting any insulin resistance, which is also a very good thing.

I don't know if you have to wait 4-5 hours, but certainly 1-2 hours is more than enough for the effects above.

You won't start catabolizing muscle until after something like 16-20 hours. As trjones mentioned, BCAAs are also good for preventing muscle loss. So obviously make sure that during your eating window, you eat enough, and on rest days that you actually rest.

Congrats on the fat loss. :)

There have been some good answers here already, with sources.

I'd like to offer just my personal experience..

I IF with a 4-hour feeding window, and the rest is water fasting. Initially I lost quite a bit of muscle, but after a couple months I was able to eat more, and my body became more adapted to fasting, and I started gaining muscle again.

I encountered a similar issue when I started doing high intensity cardio, sometimes as early as 9:30am and not eating till as late as 8pm. But once again my body adapted and my weight returned.

Currently I do as much or as little activity as I like each day (including hypertrophy inducing exercises) and muscle can still be gained simply by eating more, despite doing a training session and not consuming any calories till 8, or so, hours later.

In my experience PWO meals are beneficial, but by no means required. This is just my experience though.

This study ... http://www.ncbi.nlm.nih.gov/pubmed/17095924 ... compared protein/carb supplementation 1 hour before and after resistance training with the same supplement 5 hours before and after training.

I have access to excerpts from the full text. They measured strength gains in three different lifts. In one lift the timing didn't make any difference. In the two other lifts (squat, bench-press) the one-hour protocol had some benefit. After 10 weeks of training, for example, the 1-hour protocol was worth an extra 6 pounds in the 1RM for the bench-press.

You can draw your own conclusions.

I'm starting a little IF experiment myself and am looking to follow an 8-16 plan (8 hr feeding window, 16 hr fasting) along with a 5/3/1 lifting program.

I asked for some feedback on the Paleo Reddit group and you might find some of the responses interesting... http://www.reddit.com/r/Paleo/comments/u5a9b/if_intermittent_fasting_results_and_experiences/

I've only been following the IF plan for about 5 days now and so far I'm feeling subjectively good. I am also tracking weight, body fat, measurements, etc. so I will be able to watch any changes that manifest along with performance metrics like numbers for bench, squat, etc.

It makes sense to me to pick up BCAA supplements for pre-workout in order to spare lean tissue during intense exercise, so I will be starting those when I begin the lifting program this Friday.

It's ok .