He's spent decades in operating rooms, standing over patients as he repaired their hearts.

At a time when 63-year-old Dr. Tyrone Krause could be winding down his career and mapping out the best beaches to enjoy a drink, he's instead brushing up on push-ups as he prepares to leave for the Navy's Officer Candidate School.

“Sometimes I wonder what the hell I got myself into,” Krause said, chuckling. Krause obtained a waiver to commission into the U.S. Navy Reserve in July. He was inspired to join after his daughter, Ensign Laura Krause, earned her Navy commission in 2015.

Krause, the first in his family to graduate from college, works as the head of the Department of Thoracic & Cardiac Surgery at Jersey City Medical Center. He performs about 250 open-heart surgeries every year.

His expertise attracted the attention of the Navy during his daughter's commissioning ceremony. So, with his daughter at his side - and after receiving a waiver for his age - Krause was sworn in as a commander onboard the USS Ramage in Norfolk, Va., on July 13.

Although Krause knows he may have to work in austere environments while earning less money than a civilian cardiothoracic surgeon, he had been looking for a fulfilling way to spend his time. With his daughter's service as an example, he decided to go through with a military commissioning - and hopes others in his situation will follow.

As his story spreads, he has fielded questions from other physicians about military commissioning.

“People do look at it and say this is an abnormal thing,” Krause said. “It's not for the money. You have to be dedicated people.”

In October, Krause will attend OCS in Rhode Island. He'll be doing drill weekends in Sandy Hook, N.J., and traveling wherever the Navy needs him.

His role will include teaching advanced trauma skills to corpsmen, he said.

He may be the top doc in his operating rooms, but Krause said he is just like everyone else when he drives through the gate on base. He's ready to work his way up and give back, he said.

“Nothing rewarding is pain-free,” he said. “Most good things in life that are ultimately worth anything require some pain along the way.”

Amanda Dolasinski is MOAA's staff writer. She can be reached at amandad@moaa.org. Follow her on Twitter @AmandaMOAA.