Fasted training?

emmab0902

I have read a lot about intermittent fasting and strength training but keen to know if it's compatible with endurance exercise. I do about an 18:6 daily approach and usually break my fast after my post work workout. Have been doing this for about 2 years and love it!!!

I have just taken up running while laid off swimming with shoulder issues and am three weeks into a half marathon training plan and so far have done all my runs including my long run (up to 16km) fasted with no ill effects. But wondered if there are drawbacks to training fasted. Or if anyone has seen good results or know the possible benefits of doing long distance running in a fasted state??

sjohnny

I run fasted and don't have any problems. If I eat within a few hours of running I'll cramp up and get pukey. My longest run has been 16 miles. Long runs are usually first thing in the morning and I don't eat anything after getting up. As far as continuing to fast after running this probably won't be an issue for shorter runs but there is some research indicating that glycogen replenishment is most effective within a short period of time following the long run (like runs over two hours so you probably aren't at a point where it makes much difference yet). Last year when I was training for my first two half marathons I never ran more than 11 miles or so (maybe 12 I can't remember) and I would be done running by 9:00 and usually not eat until after noon. I did fine. I feel like I'm recovering better from 14+ mile runs now by eating a little something when I get home.

This is the answer for me that I've learned through trying it different ways.

ATT949

I have read a lot about intermittent fasting and strength training but keen to know if it's compatible with endurance exercise. I do about an 18:6 daily approach and usually break my fast after my post work workout. Have been doing this for about 2 years and love it!!!

I have just taken up running while laid off swimming with shoulder issues and am three weeks into a half marathon training plan and so far have done all my runs including my long run (up to 16km) fasted with no ill effects. But wondered if there are drawbacks to training fasted. Or if anyone has seen good results or know the possible benefits of doing long distance running in a fasted state??

"fasted" = not eating before a run or does "fasted" mean that you avoid food for hours or days before the run?

We perform best when we are supplying 60 gm/hr of carbs to the body. If it's in the body (liver or muscle glycogen) or if it's ingested during exercise, the body doesn't care.

If you're fasting rather than "in a fasted state" (meaning no breakfast) or if you run long enough to deplete your reserves of CHO (> 20 miles +/-) you may "bonk" and, if you do, you'll definitely know it. It's not harmful but you will definitely slow down.

I would not fast after a strenuous run. We improve because we overstress the body and then allow it to recover. The stress doesn't make us stronger/faster/able to jump higher, it's the recovery that does that. If we're doing slow running for a short period of time, we're not stressing the body very much but if we're doing extended runs or hard activity, recovery becomes very important. And taking in carbs and protein (4 to 1 ratio) within an hour of exercise (some writers claim within 30 minutes) is important for the recovery process. It's not harmful to the body to continue to fast after a strenuous run but it will delay recovery and will tend to reduce the training benefit.