I'm with canadianhitman on the sugar/caffeine before a workout. I don't find the fat makes me sluggish at all while I"m in the gym. In fact, I rather enjoy sitting down with my double/double and a banana nut muffin at the table that's in my gym (there's an area with a big-screen tv, two couches, and a table) about 20 min before I intend to start lifting. It's so funny to watch all the keto dieters damn near cry when they walk by and see what I'm having.