Day 4 in Polyphasic Sleep ChallengeMarch 31, 2018 in Polyphasic Sleep Challenge tagged challenge / polyphasic sleep / sleep cycles by Armin Day four in Polyphasic Sleep ChallengeFourth day in Polyphasic Sleep Challenge. It was the most difficult morning so far. Watch the video and find out more 🙂 [adzbuzzer]Read more about the challenge itself.