The drowning of two university basketball players in the Philippines has raised concerns about the extreme training conditions and pressures surrounding student athletes in the country’s highly commercialised collegiate sports industry.

Incoming rookie player Rene Baterbonia, 19, and Nigerian student-athlete Divine Adili, 21, died on Monday during a school-sanctioned “team-building activity” in Dipaculao, Aurora, on the east coast of Luzon island.

Both played for the Blue Eagles of Ateneo de Manila University, one of the country’s most prestigious private schools and a powerhouse in the University Athletic Association of the Philippines (UAAP), the nation’s premier collegiate league.

The tragedy exposed how young players could be pushed into risky training environments as universities competed for prestige, alumni support and sporting success, former athletes, sports safety advocates and collegiate sports insiders said.

Police said on Monday that initial findings showed Baterbonia and Adili had been “carried by a strong current” while swimming in the open sea. A day later, they said there was no indication of foul play and described the deaths as a “natural accident”.

But as questions and speculation grew, Ateneo issued a fuller account three days after the drownings, saying the team had been “engaged in a conditioning exercise in knee-deep water near the shoreline when they were suddenly engulfed by massive waves and a powerful rip current”.

“While most of the players managed to fight their way back to safety, Rene and Divine were pulled away,” the university said, disputing rumours that ankle weights had been placed on the athletes during training.