I regularly do 20 hour fasts and in the past have done twice weekly 36 hour fasts for weeks on end. I also tried a few longer fasts.
Since starting keto style eating in April I haven’t done fasts above 20 hours.
I find if I want to do any activity, I do much better not eating until after the activity.
The most active thing I do is Agility with my dog. I don’t run, but the concentration and the little bit of adrenalin can leave me a bit wobbly on finishing (I have a bucket chair at the finish) That wobbliness is much reduced since combining keto eating with on-the-day fasting. I had thought I might have to give this all up (again) in March this year, but keto, combined with fasting til after I’ve competed has allowed me to continue with what I love.
This is an competition round from the weekend past.
PS This lovely judge complimented my Finn, by telling me I had a “remote control dog”. I was so proud - most people run to every single obstacle with their dogs, so we are a bit different.
PPS I have been quite ill with ME in the past - for 3 years I walked no further than the bathroom and back daily. The big step up I had was after taking an anti-retro viral drug for a year. The fasting and keto is just fine tuning. They did not produce such a big improvement as the drug.