[1] Almeida made his official debut at the 2008 Summer Olympics in Beijing, where he competed in the men's 200 m breaststroke.

[5][6] Almeida blasted a 2:15 barrier and a new Portuguese record of 2:13.34 to top the second heat, but he finished only in thirty-second overall from the preliminaries.

[7] At the 2012 Summer Olympics in London, Almeida qualified for the men's 100 m breaststroke by establishing a Portuguese record and achieving a FINA B-standard entry time of 1:01.19 from the European Championships in Debrecen, Hungary.

[8][9] He challenged seven other swimmers on the third heat, including fellow two-time Olympian Martin Liivamägi of Estonia.

Almeida also became the first swimmer in school's history to claim a title at the NCAA Division I Championships in Federal Way, Washington.