Exercising while fasting?

emilyjanexvi

Does it have any benefits? Because I find it very difficult to run while fasting because I have so little energy.
I only fast one day a week, so should I use that as my rest day?

Cherimoose

I'd rest. Muscle is burned as fuel when exercising in a fasted state. Not an optimal state to be in.

Personally i'd fast whenever i felt i needed it, not on an arbitrary schedule, and definitely not weekly. I'm too active for that.

Elise4270

Agreed. I wouldn't do any exercise when fasting.

ninerbuff

Not necessarily. We all have stored glycogen. Say someone eats 30 minutes before training. Do you actually think that that food you ate converted to glycogen in 30 minutes?
I've trained fasted for quite a few years now. Makes it easier not to feel nauseous or bloated while contracting my core on heavy lifts. Most training for the average person doesn't usually exceed an hour, and that shouldn't deplete glycogen storage down to zero even with good intensity.

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Camo_xxx

The benefit would be not chucking up a meal. Some people can exercise after eating others don't tolerate it as well.

I start off on 2-3 hour bike rides from a fasted state and then eat 30 grams of carb every 30 minutes.

Sounds like you need to try eating first or some variant of it. Getting the right foods will help.

snarlingcoyote

I've always fasted on alternating days from my runs until recently. Now I eat a light lunch and that starts my fast. That evening, I go for a nice long run. I feel great during those runs and great after. I was scared of doing it until I tried. Now I'm hooked.

Cherimoose

ninerbuff wrote: »

Most training for the average person doesn't usually exceed an hour, and that shouldn't deplete glycogen storage down to zero even with good intensity.

Problems can happen well before glycogen gets to zero, as the OP noted with their difficulty running due to "so little energy". In a fasted state, blood glucose is maintained with the help of gluconeogenesis, and that increases with exercise.. which is a sign of muscle break-down. That's why i don't think an all-day fast is an optimal state to train in.

auddii

Do what works for you. If you have problems maintaining enough energy for cardio while fasting either do a lower intensity cardio or use it as a rest day.