INDIANAPOLIS – Given the encyclopedia of knowledge Andrew Luck has on a plethora of topics, not just an NFL playbook, it should be no surprise to hear the quarterback explain the reasoning for his off-season surgery.

On Monday, the Colts gathered for the first day of their offseason program.

Luck was present, participating as much as he could, and also met the media for the first time since his right shoulder went under the knife back in January.

When the 2016 season came to a close for Luck, one in which he played in 15 of 16 games but missed half of the team's practices due to injuries, it was time to decide if surgery was necessary.

"Absolutely my decision," Luck said of the surgery that has made for an abnormal offseason. "The team gave me all the resources I felt like I needed to make the best decision. This was not an off the cuff thing. I put a lot of thought and effort and time into figuring out the plan moving forward after the season. We sat down after the year, with our guys in this building and talked. Then went out and got a lot of really good opinions from a lot of really good doctors around the country.

"I made this decision with what I felt like was the best information that we could all find. I have no regrets about going to get surgery."

January surgery in California came for Luck and he's now three months into rehab.

Offering any hard timeline for Luck to return to work was not coming from No. 12's mouth on Monday.

Luck did stress that being ready for Training Camp is a goal. And the expectation for Luck remains to definitely be full-go for the entire 2017 season.

One thing Luck did reveal on Monday was exactly when his shoulder issues began.

A September 2015 road comeback victory over the Titans had its repercussions for the Colts.

That Sunday afternoon was when Luck said the shoulder started giving him trouble. Despite finishing the fourth quarter 11-of-13 for 144 yards and two touchdowns in that Week Three win, Luck was seen grimacing on the sideline after a congratulatory pat from then backup Matt Hasselbeck.

After the win in Nashville, Luck said the game "certainly was physical." The quarterback was limited at practice the following week for the first time in his NFL career. He missed the next two games before returning to play in four straight.

A month and a half after the original discomfort injury in Tennessee, a kidney injury ended Luck's 2015 season.

But the shoulder was still top of mind when that 8-8 season came to a close.

"When we sat down after (the 2015 season), we thought rehab (one Luck called "very intense") was the way to go," Luck explained on Monday. "I thought that was the absolute right decision.

"This year happened and as it transpired through this year, we sat down and felt it was maybe to do surgery on it. Certain things happen in games that you cannot control, (like) re-aggravations. We thought at the end of this (past) year, with all the information that we compiled, that (surgery) was the best way moving forward."

Luck said he has no regrets with the rehab route chosen after the 2015 season, and now the surgery move earlier this year.

The non-surgical path Luck decided on last year didn't seem to directly impact his play on Sunday's. Luck ended 2016 with easily the second best individual season of his career.

But getting to Sunday's each week was no easy task.

"There were a couple of times during the year where I would get hit in an awkward position, in an awkward way and it wouldn't feel great," Luck said on Monday.

"It would be a taxing effort to get ready for the next week and the next week. And I didn't feel like I could go through that and be productive."

Hence the reason for surgery in January.

The sling on Luck's right arm has been removed and he took part in some weight-room activity on Monday.

Once Luck was done with the media on Monday he was headed for his second treatment session of the day.

"There's a plan that involves rehab, lifting and running," Luck said, keeping any rehab specifics to himself. "There's certain things I can do with the group and certain things I cannot. And I do the best I can within that plan. Certainly, I might not be able to throw yet. I might not be able to take snaps with the guys and run handoffs and do all that jazz.

"Obviously, there's always the uncertainty (of a surgery), like anything, but I fully trust when the doctors say I'll be 100 percent, I'll be 100 percent."

The analysis from those producing content on Colts.com does not necessarily represent the thoughts of the Indianapolis Colts organization. Any conjecture, analysis or opinions formed by Colts.com content creators is not based on inside knowledge gained from team officials, players or staff.