What should be the gap between our detox juice and any kind of physical activity such as yoga, exercise, running, etc?

After exercise: It is best to have juice 5-10 minutes after any exercise to allow the body to come to its normal functioning. 

Before any physical activity: In case you're having juice before doing your exercise, it is best to keep a gap of 15-30 minutes gap between juice and exercise (this would depend on the intensity of your exercise. If you're doing light exercise, it's alright to keep lesser gap. If you're doing rigorous exercise, it is best to keep at least 30 minutes of gap).