Background: Starting weight 188 lbs., 5'9", body fat around 10%. In pretty good shape already and have been strict paleo/low-carb (~50-100g/day) for about 2 years. Work out about 5 days a week with mixed resistance, HIIT/Tabata and traditional cardio. I have been plateaued at this weight for about 12 months and wanted to try this to spark some additional fat loss. Goal weight is 172. Week 1 - Started with a 24h fast on Sunday. Since then fasting from 8p to 12p (16h) and eating between noon and 8p. Allowing myself one protein shake during the fast. The first day was rough. Since then it's been getting easier. Had some trouble sleeping the first few nights. I actually seem to be more alert in the mornings without breakfast, but I definitely slow down after my first meal, probably because it is much bigger than I am used to. I have been more irritable in the mornings as well but I feel mentally sharper. Initially workouts were a drag fasting, but now seem to be getting back to normal. I seem to be losing some size in the arms but definition is improving. The biggest problem is keeping my calories up (never thought I'd have that problem). Shooting for about 2,000KCal/day, probably getting 1500 at most. After that first "break-fast" meal I don't have any appetite for the rest of the day and have to force myself to eat. Weight has dropped from 188 to 186 (actually hit 184 earlier in the week) - not bad for one week. Week 2 - Starting out Sunday with another 24h fast. Wt. now 185. The second full day fast was much easier than the first. Training during fasting is now a breeze. Seems like I can do cardio forever without getting tired. The weight seems to be coming off - 6 pack is now clearly visible. On a side note, the grocery bill is also dropping.