I just finished a 21 day Master-Cleanse a week or more ago and was able to exercise like a champ. I would start every morning (after the SWF (Salt-Water-Flush) was out of my system) with a 4 mile power walk carrying 2 lb weights in a VERY hilly area. I would also go on about a 6 mile strenuous hike about 2 times each week, rollerblade for 7 miles about 4 times each week and 45 minutes of crunches and 5 lb weight lifting about 4 days each week. Seriously...i was exercising at least 2 times everyday. A couple of times I did get wobbly rollerblading when it was too hot but I found that if I brought along a small bottle of the lemonade it REALLY helped me power through everything. I get crazy energy when I'm cleansing. And since finishing I am completely maintaining the workout regime with just as intense an energy level. Good luck to you!!