Smith, who missed the final game of the 2014 season after having lacerated his spleen the previous week, has been cleared to play.
"A few weeks after our season, that was kind of the timeline they had given me that I would be fine," Smith said Monday as the Chiefs began their organized offseason conditioning workouts. "At that point, really the only things I couldn't do was heavy contact, sports.
"When the season was over ... it really didn't restrict me. Really it was kind of normal life. I could work out, I could run, I could do everything I needed to do. I just kind of went about my business. At this point, it's felt great for quite a while."
Smith was able to throw to Chiefs receivers on Monday. He worked with Jeremy Maclin, the Chiefs' big free-agent signing, for the first time.
"Smooth," Smith said of Maclin. "Great body language -- easy to throw to."