Bosio said it's the toughest thing he's ever done -- and admits it won't speed up his deliberate walk to the mound -- yet he's also quick to admit the pain and discomfort are nothing compared to what anyone diagnosed with cancer has to endure.
Bosio, 49, knows only too well about cancer. His mother died two years ago at Christmas after a long fight with Hodgkin's lymphoma.
"She battled it her whole life," he said. "I was the eldest son and had to take care of my brother and sister while my dad was working two jobs to make ends meet. I lost my brother to lung cancer. My dad had kidney cancer. My mother-in-law and father-in-law have had cancer. My wife's had cancer.
"It's something I've dealt with when I was a pitching coach with the Tampa Bay Rays. We all have people we know and loved ones affected by it. It's something near and dear to my heart."
Which is why he created the Bosio Foundation 16 years ago to raise money for cancer and leukemia patients. The Cubs joined him in his efforts, and last spring, the team made a $20,000 donation through Cubs Charities to Bosio's Foundation.
"It's a great gift," Bosio said. "It's another way the Cubs organization and the Ricketts' family works."
The Cubs and Bosio are hoping fans can help, too. Starting Tuesday via MLB Online Auctions, you can bid on items from several Chicago players as well as autographed baseballs by recently crowned National League Most Valuable Player Buster Posey, Chipper Jones, Prince Fielder, Tim Lincecum and Barry Zito, and an autographed Bo Jackson jersey. Other items include an autographed jersey by Chicago Bears linebacker Brian Urlacher and souvenirs from the Blackhawks.
The auction will be live until Dec. 9 at 8 p.m. CT, and all items are guaranteed to ship by Dec. 14, so if you're looking for a holiday gift, check it out. All proceeds will go to Bosio's foundation.
"That money we raise from the auction is going to help families who come into the Chicago area for cancer and leukemia treatments and need financial assistance," Bosio said Saturday. "A lot of families use their vacation time to get the treatments. The money we generate will go into that fund, and the hospitals can dictate where that money goes.
"A lot of times, the little things get overlooked. They're cancer patients, and some of them don't have great insurance, and they've been paying for treatments for a long time. I was one of those kids growing up, and remember that. It's something I can relate to personally."
Bosio was the Rays' pitching coach in 2003 but left after that season to move to Appleton, Wis., to take care of his wife's family. The holidays are a little tough because of all the memories. Two years ago, Bosio said they flew to California to celebrate Christmas, but when they landed, he got word that his mother had died.
"Instead of a Christmas celebration, it was a celebration of life with all our family and friends," he said.
His wife, Suzanne, lost her father last year around the Thanksgiving holiday.
"We all have somebody in our family and know somebody or a neighbor or a really good friend who has gone through this," Bosio said. "This is easy for me to do, because I know how hard it was for my mom and brother to go through stuff."
It wasn't an easy decision to get both of his knees replaced.
"It was tough," Bosio said, adding a few more adjectives that won't make this story. "The one thing I kept thinking was, this is nothing compared to what people with cancer have to deal with. It puts things in perspective."
But why do both knees at once?
"I guess I'm a glutton for pain and punishment," he said, laughing. "I just wanted to get it over with."
Besides rehabbing five days a week, Bosio is busy helping 300 kids train at XLR8 Sports Training in Appleton, and providing baseball instruction as well as guidance regarding strength and conditioning work. The pupils are hoping to get an edge for the next baseball season -- and possibly a scholarship or a scout's attention. One of his clients gave him a lounge chair to sit in.
"For the first couple of weeks, I'll be sitting in a chair and directing and barking orders," Bosio said. "A lot of the stuff we do, we do [with the Cubs], and I try to tell my clients, 'We're training you as professionals. That's where you guys have to get your edge and be able to separate yourself from other kids.'"
Bosio isn't alone in his battle against cancer. Cubs first baseman Anthony Rizzo, a cancer survivor himself, will host his first "Walk Off for Cancer" event on Dec. 9 in Parkland, Fla. Outfielder David DeJesus and his wife, Kim, who have tried to raise awareness regarding ALS, are planning a fashion show with Cubs players and their wives in January before the Cubs Convention.
At Thanksgiving, it's a good time to take a moment and give thanks to those making the extra effort for others in need.
"Hopefully, at some point, we can find a cure and help even more people," Bosio said. "It seems we have a lot of guys who have one thing in common and that's helping other people. That's what makes me most proud."
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.