Rescuers were continuing to search for a missing sailor, identified as boat safety officer Roger Stone.
The search started after the 38-foot Cynthia Woods missed a radio check Saturday morning. The crew included four college students and two safety officers.
A helicopter crew from Air Station Houston pulled the five men from the water 23 miles south of Freeport, Texas, Petty Officer Renee C. Aiello said Sunday. They had drifted about five miles northwest of their capsized boat.
They were taken to the University of Texas Medical Branch in Galveston, where all five were listed in good condition. They were suffering from sunburn and dehydration, said R. Bowen Loftin, CEO of Texas A&M at Galveston.
"I've talked to all of them and they're all doing fine," he said. "They were extremely happy to be alive."
Three of the students - Steven Guy, Joe Savana and Travis Wright - attend Texas A&M at Galveston, the school said in a news release. The fourth, Ross James Buzbee, attends Texas A&M in College Station, the school said.
The other safety officer was identified as Steve Conway of Texas A&M at Galveston.
The boat, which lost communication around midnight Friday, was competing in the Regata de Amigos. The race, which covers 610 nautical miles from Galveston to Veracruz, Mexico, started Friday and continues into next week.
Coast Guard officials said the keel of the overturned vessel was ripped off, indicating the sailboat may have hit something in the water, according to the school. Race director Kevin Box said the loss of the keel can cause a boat to overturn in seconds.
The five who were rescued stayed afloat with four life vests in 4 to 6-foot seas, Loftin said. A few were below deck when the boat capsized. They said Stone was not among them when they went into the water, Loftin said.
It was Conway who kept the group together in the water and used a flashlight to signal Coast Guard searchers, Loftin said.
The boat went missing 11 miles south of Matagorda, which is about 110 miles down the coast from Galveston.