Yes you can and you should!
Exercising improves your body’s functions and increases the effects of detoxification.
Although there is a decrease in caloric intake during the program, many of our detoxers report increased energy.
However, if you are an extreme athlete, marathon runner, etc., you may find that the detoxing process “takes a lot out of you.” That’s because your body’s focus WANTS to be the cleansing process.
Running 26 miles, for instance, while also in a heavy phase of detox (such as week 1) probably isn’t a very good idea. You may feel weaker, as your body sloughs off lots of toxicity in a short time.