After all, the former Arkansas defensive tackle stands 6-foot and weighs 305 pounds. His body doesn't appear to be built for activities such as yoga.
But Jackson has gone to great lengths over the past month to prepare for this week's NFL Scouting Combine in Indianapolis. That includes doing yoga twice a week for 90 minutes to improve his flexibility and show he doesn't have "stiff hips."
"It was awkward. I thought yoga was just for women," Jackson said, laughing. "It got me a lot more flexible."
Over the next four days, Jackson and four other former Razorbacks will go through a battery of tests and interviews -- all with the hopes of performing well enough to improve their status in April's NFL Draft.
Former Arkansas defensive end Jamaal Anderson, cornerback Chris Houston, offensive tackle Tony Ugoh and linebacker Sam Olajubutu will be among those who will be measured, weighed, interrogated, timed and put to the test at the combine.
A good showing by a player like Houston could mean the difference between being a first-round pick or falling to a later round. For players like Jackson and Olajubutu, they hope to simply prove that they're not too short or too "stiff" to play in the NFL.
"It's really important," said Olajubutu, who has spent the past few weeks working out with Jackson in Philadelphia to prepare for the NFL combine. "I just want to show them what I can do, that I have all the tools to play at the next level."
In 2005, former Arkansas quarterback Matt Jones used the combine to impress NFL teams and solidify his place as a first-round pick by posting a 4.3 time in the 40-yard dash. Every year, there are other "workout wonders" who improve their draft status with impressive numbers at the combine.
But NFL scouts, coaches and general managers will have to wait until Arkansas' Pro Day in early March to get a good look at Anderson, a likely top 10 draft pick.
Anderson said Wednesday that, while he'll go to the combine, he won't take part in any of the running drills because he tweaked a hamstring while working out a month ago in Los Angeles.
"It's a little nagging," said Anderson, who still intends to go through the weightlifting drills and interviews at the combine. He'll run the much-scrutinized 40-yard dash at Arkansas.
But for the other former Razorbacks, this is a big weekend.
One of the knocks against Olajubutu is that he's undersized to play in the NFL. But he has been working out twice a day, five days a week, to trim his weight, increase his speed and add more strength to his 5-foot-9, 224-pound frame.
The NFL combine will be Olajubutu's chance to show if all the work he and Jackson have done together since the end of the season was worth it.
"It's not like preparing for a game. It's different," Olajubutu said. "You want to prepare to run and show yourself off a little bit."
Houston has a good chance to do that. While at Arkansas, he was considered a "numbers guy" because of his ability to post a fast time in the 40-yard dash, as well as bench-press more than 400 pounds. The NFL combine is especially important for him.
"I think he'll help himself big time," Arkansas coach Houston Nutt said of the cornerback. "I think he'll shoot over the charts because his 40 time is going to be great, his bench press is going to be phenomenal, his vertical jump is going to be awesome, his 5-10-5 is going to be something.
"This is where 'Batman' (Ahmad Carroll) helped himself, so I expect the same formula for Chris Houston."
NFL Scouting Combine
Where: Indiana Convention Center, Indianapolis
Schedule: Today (Offensive linemen, kickers, punters, long snappers, tight ends); Friday (Quarterbacks, running backs, wide receivers); Saturday (Defensive linemen, linebackers); Sunday, (Defensive backs)
Name Pos. Camp Jersey No.
Jamaal Anderson DE 06
Chris Houston CB 21
Keith Jackson Jr. DT 25
Sam Olajubutu LB 24
Tony Ugoh OT 46
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