[8] At the 2004 Junior European Championships, he won the bronze medal on the rings and placed fourth with the French team.

[9] Then at the 2006 Junior European Championships, he won the gold medal on the rings, and he placed eighth with the French team.

[13] Aït Saïd won the silver medal on the vault at the 2011 European Championships behind his teammate Thomas Bouhail.

[16] Aït Saïd fractured his right tibia in three places at the 2012 European Championships during the team final, and he could not compete at the 2012 Summer Olympics.

[7][18] At the 2013 European Championships, Aït Saïd tied for the gold medal on rings with Ukraine's Igor Radivilov.

[23] He helped the French team win a 2014 friendly meet against Belgium and Spain with the highest scores on rings and vault.

[25] Aït Saïd won the silver medal on the rings at the 2015 Ljubljana World Challenge Cup.

[27] At the 2015 World Championships, he helped the French team finish 10th,[28] and he placed fourth in the rings final.

[33] In the qualification round of the Olympic Games, Aït Saïd suffered a double compound fracture in his left leg while landing badly on the vault.

[36] Aït Saïd returned to competition thirteen months later at the 2017 Paris World Challenge Cup and won the silver medal on the rings.

[42] At the 2019 Paris World Challenge Cup, he tied for the gold medal on the rings with Egypt's Ali Zahran.