KEY LARGO, Florida (AP) — A university professor broke a record for the longest time living underwater without depressurisation this weekend at a Florida Keys lodge for scuba divers.

Joseph Dituri’s 74th day residing in Jules’ Undersea Lodge, situated at the bottom of a 30-foot-deep lagoon in Key Largo, wasn’t much different than his previous days there since he submerged March 1.

Dituri, who also goes by the moniker “Dr Deep Sea,” ate a protein-heavy meal of eggs and salmon prepared using a microwave, exercised with resistance bands, did his daily pushups and took an hour-long nap. Unlike a submarine, the lodge does not use technology to adjust for the increased underwater pressure.

The previous record of 73 days, two hours and 34 minutes was set by two Tennessee professors — Bruce Cantrell and Jessica Fain — at the same location in 2014.

But Dituri isn’t just settling for the record and resurfacing: He plans to stay at the lodge until June 9, when he reaches 100 days and completes an underwater mission dubbed Project Neptune 100.

The mission combines medical and ocean research along with educational outreach and was organised by the Marine Resources Development Foundation, owner of the habitat.

“The record is a small bump and I really appreciate it,” said Dituri, a University of South Florida educator who holds a doctorate in biomedical engineering and is a retired US Naval officer. “I’m honoured to have it, but we still have more science to do.”

His research includes daily experiments in physiology to monitor how the human body responds to long-term exposure to extreme pressure.

“The idea here is to populate the world’s oceans, to take care of them by living in them and really treating them well,” Dituri said.

The outreach portion of Dituri’s mission includes conducting online classes and broadcast interviews from his digital studio beneath the sea. During the past 74 days, he has reached over 2,500 students through online classes in marine science and more with his regular biomedical engineering courses at the University of South Florida.

While he says he loves living under the ocean, there is one thing he really misses.

“The thing that I miss the most about being on the surface is literally the sun,” Dituri said. “The sun has been a major factor in my life – I usually go to the gym at five and then I come back out and watch the sunrise.”