21 days would probably be too long for me, are you very fit or carrying extra weight?
Trying to understand why you would go that long 🤔
Discussion
Not like marathon fit but walking 15-20 miles a week, occasional 4 mile run and gardening chores which can be a workout digging, moving mulch, compost etc. My weight was upper 150s @ 5'9" not really "overweight" but not ideal either. My motive was the challenge/discipline of it along with a deeper cleansing than I could get in 7 days.