Lester already noticing positive effects of parathyroid removal

Though he didn't quite know it at the time, Jon Lester does know he wasn't feeling right at least a year ago.

The veteran left-hander, who has built a legacy as one of baseball's true workhorses, noticed he didn't have as much energy as he used to. He would take the mound at Wrigley Field at times last season and feel way more fatigued than should've been at that stage of a game.

"There would be times where I would run out in the fifth, sixth, seventh inning and feel like I hit a brick wall," he said today during a Zoom session with reporters. "There were times last year where I would come out of the bullpen and be like: 'God, did I pitch the game already?' "

Lester, 36 at the time, initially chalked it up to his advanced age and the mileage that comes with a long career. He figured the answer was to work out more, lift more weights, run a bit longer. But as he spoke to other veteran pitchers and asked how they felt as they got older, none shared a similar story.

It was only after several rounds of medical tests and routine bloodwork that Lester finally had an answer: He wasn't fatigued because of his age. He was fatigued because he had hyperparathyroidism: a condition in which one of his parathyroids, four small glands in the neck that surround the larger thyroid and are responsible for regulating calcium levels in the body, was producing too much hormone.

He scheduled an appointment with an endocrinologist in New York last week, had an approximately one-hour parathyroidectomy (surgery to remove a parathyroid gland) Friday and now is back in West Palm Beach, Fla., feeling invigorated and hoping this could help him become the pitcher he had always been throughout a long and successful career with the Red Sox and Cubs.

"I feel, already less than a week (since surgery), I feel a lot better just energy-wise," he said. "Doing my workouts and stuff like that, I feel better. I think that's the main goal: to feel better physically. And now I've got the peace of mind that this thing is done."

Lester described his condition and the subsequent treatment as "very minor." Because doctors removed only one parathyroid and the other three (in addition to the thyroid gland itself) are functioning well, he won't need to take any medication and there won't be any long-term effects.

Given Lester's medical history - he underwent chemotherapy for lymphoma in 2006 - many wondered if this condition could be related in any way. He was confident throughout the process that was not the case.

"The cancer stuff really never crossed my mind, thankfully," he said. "A lot of the kind of signs of that, I wasn't going through. So I knew that this was something different. ... The cancer stuff, no, thank God that stuff hasn't really crossed my mind for a long time."

Lester is now sporting an incision scar across the base of his neck, and he'll need to be careful over the next few days to make sure it doesn't open up. But he's already played catch with no problems and plans to ramp up his throwing in the coming days, first pitching off the bullpen mound, then facing live hitters before ultimately pitching in a Grapefruit League game.

Lester and the Nationals believe he can still open the season in a rotation anchored by Max Scherzer, Stephen Strasburg and Patrick Corbin, and likely rounded out by Joe Ross. But given the excess of talent and experience the club already has in those first three slots, not to mention several off-days in the early April schedule, he knows it wouldn't be too damaging if his 2021 debut is pushed back just a bit.

"As far as my arm and body, I feel like I can ramp right back up and be right there," he said. "I may be a tick behind, but I think we can kind of catch up on the backside of that rotation."

Whether the parathyroid removal has a positive effect on his pitching performance remains to be seen. But it's worth noting that from 2008-16, Lester averaged 6.4 innings per start, a number that dropped to 5.6 innings from 2017-20 and bottomed out at 5.1 innings last summer.

"I think because of what was going on in my body, I wasn't able to recover," he said. "I wasn't able to hold the electrolytes. I wasn't able to hold the water and my body would just fatigue. And when you don't know what to look for and all this stuff, I think you just think: 'I'm just not in shape. I'm not prepared to pitch.' And that's a hard pill for me to swallow. That's what led me to start asking these questions."