I do my full weight lifting program on a similar fast with no problems. Once the body switches to fat for energy I feel better in my workouts. After a couple days I do feel sluggish at the beginning but after and warm and going I feel really good. My workouts are every-other day, full body with free weights, cables, and machines, and they run 90-120 minutes. I go to work about 1-2 hours later that has a lot of walking and as long as I stay active I’m feeling good.