According to Dr. Rassman, who is a great HT authority and a HT pioneer, you can assume almost any type of exercise 3 days post op in case of FUE. Me too, I am a gymnast and started my handstand routine 7 days post op. I didn't have any issues, might have even improved the blood circulation in the head. Just be mindful not to hit your head against something... but 4 weeks post op you are totally fine.