The up-and-down nature of Doug Martin's NFL trek – two massively successful Pro Bowl campaigns, several others marred by injury – has made each year of his career seem like its own self-contained story. Usually, that story began in the spring, when the Tampa Bay Buccaneers would begin preparing for the upcoming season.

In 2015, for instance, there were immediate indications that Martin, after two injury-plagued and unsatisfying seasons, was at the top of his game in May OTAs. That momentum carried over into training camp and then into the regular season, in which he ran for 1,402 yards to finish second in the NFL.

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Martin's 2017 is different, however. This time, his story began in January. By the time the Buccaneers' OTAs rolled around, the sixth-year running back had already been on an important journey of his own, and he had come out a stronger man at the end.

"It was a journey these past few months with the statement and having to go get help," said Martin. "It was a good journey of self-development and I learned a lot about myself and I got stronger. I've had the support of my family, friends and fans and my teammates all around and I'm happy to be back here."

Martin's statement last December came in the wake of a four-game NFL suspension for violating the league's drug policy. As he notes in that statement, he subsequently entered a treatment facility to deal with the personal issue, for which he has chosen not to reveal the specifics. Martin also chose not to speak about the length of his treatment – "long enough," he said – nor offer any additional details. However, he did say that the treatment was a success.

"It's behind me," said Martin. "It is definitely behind me."

Martin was relaxed and upbeat on Thursday after the Buccaneers' most recent OTA as he spoke about his journey for the first time. In addition, he has drawn strong reviews for his practice work so far this spring, just as he did in 2015. Martin clearly feels as if the help he sought after last season has put him back in position to succeed once again in his chosen profession.

"It was definitely worth it," said Martin. "I definitely turned a negative into a positive and I'm out here and I'm definitely a stronger person because of it. I was [in treatment] to the point where I'm strong now, mentally strong and physically strong.

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"I am a stronger person individually, mentally and physically, better on and off the field."

Martin says he has had little trouble working back into the mix inside team headquarters or out on the practice field. That process was eased, of course, by the help and acceptance offered by his teammates. Martin specifically mentioned teammates Jameis Winston and Gerald McCoy as well as General Manager Jason Licht and Head Coach Dirk Koetter, thanking them and the rest of the team for remaining behind him and providing support. Taking handoffs again has been the easy part.

"I was fine because when I went through treatment, they prepared me for everything that I'm dealing with right now and it's a piece of cake right now," said Martin.

Martin also said he's past the hamstring troubles that cost him a lot of playing time in 2017, and that has been evident on the practice field. And if he happens to look just as sharp now as he did before his big 2015 campaign, there are people at One Buccaneer Place taking that as a good sign. Martin will still miss the first three games of the season on that aforementioned suspension, and it's fair to say the Buccaneers are still working out their plan for the backfield as a whole, but these spring weeks on the practice field have certainly been encouraging, for more than one reason.

"I think just from my own experience, when Doug is practicing like this – when he's finishing plays, when he's got that burst, got that pep in his step – it's carried over to the field," said Koetter. "We have a ways to go, we've got to get through preseason. We've got to get through preseason games healthy, Doug has got to stay healthy. There's more things that have to happen. Again, time is on our side. I know everyone wants to know, they're anxious to know. There's just nothing to know right now, we've just got to wait this out."