Hi. Maybe she fells sleepy even on OMAD diet because of her exercise (running/jogging as she said). Maybe she push herself to her limit that is why she get tired and feels sleepy.I don't know how you can sleep during the day, if you eat the OMAD way. My experience with this diet is that when you are on it, you have more energy. Normally its hard for me to wake up in the morning. However I have realized that since I started this diet I have more energy,and get up instantly without my 4 alarm clocks having to go off. So I definitely can't sleep in the afternoon because I'm so full of energy and enthusiasm. However to each his own.
From what I have gathered regarding sleep during the day, it can range from a minimum of 10 to 20 minutes to a maximum of one hour. But sleeping for four to six hours within the day which is supposed to be part of our waking hours will probably disrupt our nightime sleeping hours. We all know that our bodies need at least seven to eight hours of sleep daily and sleeping it out the rest of day may be unhealthy. But this is on the assumption that we we did not lose sleep in the previous days and is just trying to make up for lost sleep like what nurses do when they have a long night shift because of their duties.