ATHENS, Ga. — Some mornings, Dana Vollmer wakes up tired and just does not want to go to practice. The swimmer, a five-time Olympic gold medalist, juggles numerous practices per week with raising two sons under 4. The strongest force pulling the 30-year-old out of bed and toward the pool comes from the college-aged swimmers at her alma mater, the University of California Berkeley.

They text Vollmer to tell her how much they love having her at practice.

“To know that they still value me being with them, and training with them and smiling at the end of the lane, meant a lot to me,” Vollmer said.

Most 30-somethings don’t spend time with the current students at their alma mater. But among U.S. Olympic swimmers, more of whom are competing into their 30s, it is a growing trend.

The 2016 U.S. Olympic roster in Rio de Janeiro featured five swimmers who were at least 30. In the previous four Olympics combined, only four American swimmers 30 or older made the team.

“I don’t know where I would go if I wasn’t allowed to train with the college team,” Vollmer said.

Katie Ledecky, who grew up in Bethesda, turned pro in late March, forgoing her final two years of eligibility at Stanford. Still, she will train at Stanford in preparation for the 2020 Olympics in Tokyo. Staying at Stanford will help her “continue to keep my focus on what it’s always been, which is on my studies and my swimming,” Ledecky said during a recent appearance at the National Press Club.

Similarly, Missy Franklin, who made her Olympic debut as a 17-year-old in London in 2012, recently relocated to the University of Georgia to train with the Bulldogs and finish college.

Swimmers are not the only Olympic athletes who continue to train at a college even after they graduate. Track and field athletes, for example, usually train wherever their coaches are. For some, that’s on a college campus.

But the trend seems more prominent in swimming: Every swimmer on the 2016 U.S. Olympic roster trained at a college at some point.

“There are really no other places to train in the U.S. other than post-grad teams [affiliated with] college teams,” said Franklin, who swam for Cal before turning pro in 2015.

Many swimmers find a college team environment is better than training individually.

“Being able to get competitive with some guys every day is really key,” said three-time Olympic gold medalist Ryan Murphy, who also trains at Cal, his alma mater. “I don’t think I’d be able to go as fast as I do without that.”

The NCAA allows swimmers who no longer are eligible to compete for a college team to train alongside one “on an occasional basis,” said Steve Flippen, Georgia’s director of compliance.

“The NCAA likes to throw in ‘occasional,’ but they don’t define it,” Flippen said. “It’s one of those things that’s on a case-by-case basis.”

The transition from juggling classes and training to solely focusing on swimming can be a challenge.

“I think it’s probably not talked about enough how hard the transition is, going from a collegiate athlete to a professional athlete,” Franklin said. “After college, you really do miss that sense of team and camaraderie.”

The swimmers at Georgia recognize the importance of staying close. On Wednesday nights, they play pool at a downtown bar.

“It’s nice because it keeps us normal,” said Olivia Smoliga, a 2016 Olympic relay gold medalist. “We’re professional athletes, which is really cool, but at the end of the day . . . I still feel like a college kid.”

For Vollmer, getting back into training after the birth of her second son was not easy. She finished last in sets and missed pace times. What helped was hearing from Cal swimmers Amy Bilquist and Abbey Weitzeil, as well as fellow professional Farida Osman.

Osman would text Vollmer the weekly schedule for workouts. “She’ll call me out and be like: ‘You better be there. It’s just me and you. Don’t leave me there,’ ” Vollmer said.

When she was nine months pregnant with her first son, who was born in March 2015, Vollmer asked Cal Coach Teri McKeever whether she could come back and train with her leading up to the 2016 Olympics. In Rio, she became the first American mother to win a swimming gold medal, in the 4x100 medley relay.

“If Teri were to leave, I would follow her, most likely,” Vollmer said. “It is finding a coach that works well with you and that you know how to communicate with.”

Thanks to the record-setting success of Michael Phelps and Ledecky, swimming has become a more viable profession. In addition to sponsorships, swimmers can earn stipends from USA Swimming of up to $3,000 per month, said national team managing director Lindsay Mintenko.

“Looking to the future, USA Swimming, with the help of current and past swimmers, can really create a better plan,” Franklin said, “and give some more options to those professional athletes who want to keep training after college.”

Georgia Coach Jack Bauerle, who helps direct the second-largest group of 2016 U.S. Olympian postgraduates training alongside college swimmers (Cal’s group being the largest), said balancing two sets of training regimens isn’t easy. He described “long nights” of creating workouts for the pros during critical parts of the college season. But Bauerle sees the benefit of having Olympic medalists in the water with his college swimmers — as do the pros themselves.

“There are little things here and there that I can do or say to help them along their journey,” five-time Olympic medalist Nathan Adrian said of the college swimmers with whom he trains at Cal. “On the flip side of that, I think they offer camaraderie and friendship to me in this journey, where swimming can be pretty lonesome and boring if you’re just doing it alone.”

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