I added crossfit on day 1 of P3! BUT not all may want to do this. If you do, it’s very likely you will not be able to stabilize in the 2 lb window – which is actually just fine/okay as long as you are mentally/emotionally ready for it. I discuss it all in detail here:
I have known a few to attempt to continue crossfit during Phase 2, during the weight loss portion of the diet, but typically how it goes is that they feel like crap doing it- happened to me as well- and can cause stalls. I’m not sure exactly the reason but my guess is that it just creates too many opposing demands on the body so then your body resists to preserve itself.
Crossfit is a “building” activity- you need more calories typically to fuel both the workouts and the muscle gains you can get from it. Whereas hCG is a “losing” activity – where you need less calories so that you can lose fat. They just don’t combine well in principle. I did attempt to continue crossfit my 4th round – I only made it through 2 days of crossfit at the start, I felt absolutely horrendous/fatigued/like-death-warmed-over afterwards, and then I had something occur that is really abnormal- a complete weight loss stall for 7-10 days (can’t remember exactly but it was LONG time) at the very beginning of my round! Stalls are normal, but they almost never occur from day 2 of the diet- that is always when you have the most weight loss. So I figured that was not the best idea so I’m passing it on.
I have a detailed blogpost about exercise during the hCG Diet here for ya.
I hope this helps!