Ah yes, water fasts go hand in hand with deliberate rest. The most experience doctors and coaches in that field advise strongly that space is made in life to accommodate a full water fast and that means only light physical exertion and lots of rest. It's been a while but I think I got up to 2.5 - 3 weeks on a water fast, with a common limit being around 4 weeks when people do it in a fasting clinic to heal specific illness.

There's a great book on the topic that's mostly online for free from nearly 100 years ago (Herbert Shelton ) - but it's still considered a classic in the field - I recommend checking it out. I linked to it in [my post on fasting from a few months ago](https://steemit.com/health/@ura-soul/fasting-as-a-therapy-for-increased-health-and-vitality-lose-fat-strengthen-immunity-heal-and-look-feel-better).