They are academic advisers and nurses and commercial real estate brokers. They teach math and guide quail hunts and run logging companies.

But about a decade ago, they played high school football in Florida, where they had the privilege of getting stiff-armed, trampled and outraced by Derrick Henry, who continued to treat tacklers as minor nuisances at the University of Alabama and with the Tennessee Titans.

As a teenager, Henry was only slightly smaller than his listed N.F.L. dimensions (6-foot-3, 247 pounds), and finished his playing days at Yulee High, north of Jacksonville, with 12,124 rushing yards, the national record. The game he broke it, against Taylor County, he ran for 482 yards and six touchdowns.

“You think you’ve done good — you’re the No. 1 tackler, have the most interceptions,” Davis Helm, a former Taylor County safety, said, “and then somebody shoots off fireworks with you dragging behind him. That’s hurt, man.”

Helm and many of Henry’s prep peers were eager to share stories of what it was like to play against the best, biggest, strongest and fastest player they have seen.

Henry, after missing nearly three months with a fractured foot, is likely to return Saturday for top-seeded Tennessee’s A.F.C. divisional-round playoff matchup with Cincinnati — and those peers will be watching. Here is what they said about him:

West Nassau quarterback Reagan Wright, a financial consultant, played football as a boy against Henry: At that age, you’d see a bunch of pudgy, 150-pound kids stepping off the bus. The moment we got to middle school and he stepped off, you’re like, “Who’s that guy?”

West Nassau cornerback Brett Woodle (5-9, 160), an academic adviser at the University of North Florida, also played against Henry in middle school: They pitched it to him and let him do his thing. He stiff-armed me into the dirt and my dad was like, “Maybe you should grow up a little bit.”

West Nassau linebacker Brandon Mattox (5-10, 210) teaches math there: He doesn’t have arms. He has legs that he calls arms.

Trinity Christian Academy linebacker Hughston Higdon (5-11, 190) is a hunting guide: He’d line up at tailback and be bigger than his linemen.

Mattox: Before the Yulee game, my girlfriend gets there early because she knows the stands are gonna be packed. I’m in the locker room getting my mind right and she knows better to call me before a game, but she calls me and says, “I need you to meet this N.F.L. player sitting in front of me. It’s going to boost you.” I get up to the stands and go, “Where is he?” I wanted a picture or an autograph. She points a few rows down, and I go, “That’s Derrick Henry, their running back.” She goes, “Oh my gosh.”

West Nassau defensive end/outside linebacker Dalton Delano (5-11, 175) is a nurse: When we played Yulee, it wasn’t a big study week. It was snap the ball to Derrick, he’d run right or run left, and can we stop him or not? And we definitely could not.

Taylor County right guard Blaine Brenner works at a building supply company: Our defensive coaches were telling our guys, “Do not, for whatever reason, hit this guy above the waist because he will turn you into a poster.” Those are the exact words.

The Bolles School defensive tackle Michael Cassidy (6-1, 265) is a commercial real estate broker: Our nose guard would pretty much jump into the legs of the center so a few guys would fall on top of him. That would take out one to three guys every play. If we were lucky enough to take out a center or a guard, that would leave some room for the tackles and linebackers. As long as you can take out his legs or trip him up a little bit and two other guys jump on his back, you were OK.

Helm (6-4, 180) works at a building supply company: When he stiff-armed me in the face mask, I had honestly never been hit that hard. All I saw was a flash. My earpiece came out and his arm didn’t even touch my skin and my eye swelled shut. I got up and I couldn’t see out of my right eye.

Woodle: As the backside corner, my job was to run that guy down because I’ve got an angle on him. By the time he had gotten to midfield, he was coasting, so I got within five yards of him, thinking, “I’m going to get this guy.” I’m not sure if he heard footsteps, but he turned and looked at me and then hit another gear that I’ve never seen before or since.

Interlachen linebacker Dijon Green (5-9, 185) is studying for his nursing boards: One of our safeties at the time got caught in the open field against him. He didn’t say this in the coaching room, but he definitely told us that he missed a tackle on purpose because he didn’t want to get run over. He was one of our hardest-hitting safeties, and he’s like, “I don’t want any of that guy.”

Mattox: We prepared by attacking the single leg instead of his hips — trying to attack the near thigh, the closest thigh — so when he tried to throw his stiff arm, you’d try to slap his wrist and make him miss your helmet or shoulder just enough to where you could attack his thigh. We did that for 15 minutes every day, Monday, Tuesday, Wednesday and Thursday.

Woodle: I went to try to tackle him one time and he stiff-armed me dead in my face. He had a hold of my face mask. I felt like I was getting punched by a boxer.

Taylor County free safety Will Tuten (6-2, 180) operates a family-run logging company: My senior year, I think he had 305 or 310, and he broke the single-season Florida record or something. I think I had three or four solo tackles. You know, I say tackles — I forced him out of bounds. Anyway, they announced it afterward on the PA system. I look up, my heart’s broken, and this dude’s taking off in a jog and doing back flips down the field in full pads.

Woodle: I see Derrick run to my side of the field, and the first thought that comes to my head was, “I’ve gotta go one on one with this dude.” I’m thinking he’s going to try and shake me. He just put his shoulder in my chest and ran me over. It knocked the breath out of me. I put that play on a highlight tape. I thought it would show colleges that I was tough enough to take a hit.

Helm: I was like, “I’m gonna put this dude out of the game.” I decided I was going to put my helmet right into his shin and try to break his leg. So I rolled into that pile and I hit him with the freaking crown of my helmet. He looked at me and said, “Don’t do that again.” I was like, “Uhh.”

Mattox: One play specifically, I thought I was hot crap. I had a solo tackle to tell my son about: In the backfield, it was a missed block. I thought really highly of myself until 10 minutes later. It was me and him at midfield. I read the play perfectly. I was in the hole. Next thing I know, my helmet’s in the dirt. His hand is on top of the helmet. By the time I look up, he’s walking into the end zone 60 yards later.

Brenner: He was probably the world’s best extra point blocker. He would just get a running start and time the snap up and be over the center’s head when he snapped the ball.

Helm: The way our coaches hyped us up was, “They’ve got fireworks over there. If he runs for over 300-something or 400 yards, they’re going to blow fireworks.” And we’re like, “We’re not going to let him. They’re gonna have to put the fireworks in the locker room.” And damn if he didn’t. They blew those fireworks, and they were bright.

Helm: My senior year, we went up there and they were going to go for 2 at the end to beat us. I was rolled up on what would be the weak side and he always ran to the strong side. He looked at my stringy [expletive] and nodded to the quarterback. I said, all right, he’s running this way. Dude, I ran out there in the flat, grabbed a hold of him and prayed that someone else was coming.

Tuten: When I wake up, I kind of think about him. I have a bunch of shoulder aches from football, and I’m sure he was the culprit.

Mattox: My junior year, we lost to Yulee by a point. That off-season going into my senior year, when I lifted weights, I would finish every set, no matter what the lift was, by doing extra sets at 240 pounds because that’s how much Derrick weighed.

Tuten: I had a great angle on him one time — I actually tackled him from behind — and I remember his foot catching me under the chin as I slid down his [expletive] tree trunk legs. It unbuckled my chin strap and knocked my top clip off.

Helm: If you hit him too high, he’d stiff arm you. If you hit him in the midsection, his legs and his hips, there’s no way to do it. You hit him too low, his legs hurt you. The only thing I could do — I was long, 6-4 and 180 pounds — was just jump on him and grab and hang on. Because you’re not going to knock him backward. My dad told me, “You’re going to think about this later on when he goes pro.” I’m like, “Neh.”

Cassidy: One of my old profile pictures on Facebook was me trying to wrap up his ankles. I’m pretty sure he got away.

Fernandina Beach linebacker Alex Vrancic (6-2, 190) is a captain in the United States Marine Corps: Maybe that’s the best way to remember that you played Derrick Henry and you made it out alive: You’re not on social media, you weren’t on “SportsCenter.” My claim to fame was staying off his highlight reel.

Mattox: My son, he’s 7, and he plays Madden with him. And every time he stiff-arms somebody, he says, “Daddy, is that what Derrick did to you?” I’m like, “Oh gosh, son. I’ve got to live with that the rest of my life.”