But the No. 1 overall pick in this year's draft was limited as he continues to recover from surgery to repair a sports hernia.
Clowney, who had surgery on June 12, participated in the majority of the drills as Houston started camp with a 2 1/2-hour practice on Saturday morning. But he was held out of 11 on 11 drills late in the workout.
The first workout was open to the public and fans cheered as Clowney trotted onto the field for the start of practice.
Others squealed and yelled his name as he walked off of it and he flashed a big smile before first taking a second to pull his flowing dreadlocks, which were drenched in sweat from the workout, away from his face.
He said he's feeling better, but isn't 100 percent yet. Despite that Clowney didn't appear to be slowed by the injury and moved around well during practice. He said it's up to the trainers if he'll be able to take part in drills when the Texans move from shorts and shells to full pads in a few days.
''I'm just taking it one day at a time,'' Clowney said. ''I'm just letting the trainers take it one day at a time and try to come back and get back for the first game.''
The Texans open the preseason on Aug. 9 at Arizona.
Coach Bill O'Brien said he'll let the trainers decide how much Clowney will do and when.
''We've got the best when it comes to that,'' O'Brien said. ''We do that and these guys are edgy, they want to get going, but it's a long season. So we bring them back at their pace. When they're ready to go, they'll go.''
The 6-foot-5, 266-pound former South Carolina standout is moving from defensive end to outside linebacker in defensive coordinator Romeo Crennel's system and believes the transition is going well.
''I'm feeling very comfortable, but I've still got a lot of work to do,'' Clowney said. ''Just keep getting better and better each day.''
He'll pair with 2012 Defensive Player of the Year J.J. Watt to beef up Houston's already solid pass rush. Clowney had 130 tackles, 24 sacks, 47 tackles for losses and 20 quarterback pressures in a three-year career at South Carolina. He also caused a school-record nine fumbles and deflected seven passes. The 21-year-old also set a South Carolina record with 13 sacks in 2012.
Watt said he's eager to see how Clowney and the rest of Houston's rookies perform in camp.
''Training camp is a good time for rookies to get their feet wet,'' Watt said. ''Once we finally put the pads on, it will be a good opportunity to see how they perform in a situation like that. So it will be exciting.''
Clowney's still soaking in the fact that he now gets to play with people he watched over the past several years.
''It's very exciting,'' he said. ''It was exciting the first time I got out here with the guys I looked up to coming into the NFL - J.J. Watt, Johnathan Joseph, D.J. (Swearinger), guys like that on my team I just I looked up to before I got here. So now that I'm here with them, it's even better.''
Clowney missed Houston's three-day minicamp because of his surgery, but got going early by participating in Houston's offseason workouts leading up to that camp. He feels as if that helped him improve since he was drafted in May.
''I'm a lot better than where I was,'' he said. ''I've learned a lot of the playbook already. Coach already said that we look good out there, so we've just got to keep pushing.''
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