Those students don’t remember the almost deafening silence or the looks of horror as fellow Americans watched from their televisions when one hijacked plane crashed into the World Trade Center — and then another.

But through the stories of others and facts they learn in class or surfing the internet, they understand and respect the sacrifices of first responders on that fateful day. First responders, who in the face of danger, continued to move forward in an effort to save the lives of others. New York firefighters and police officers who climbed the stairs of the World Trade Center as others were coming down — climbing, knowing they may not come back down alive.

“They didn’t experience it, but they can tell you the facts of the day,” said Iowa Central Fire Science Coordinator Lenny Sanders of his students. “They don’t know the emotion but they know the facts.”

On Friday morning, on the anniversary of 9/11, students paid tribute to those sacrifices by participating in physically demanding challenges.

-Messenger photo by Chad Thompson

Andy Midtling, a Fort Dodge firefighter, takes a breather after completing several burpees Friday morning at the Iowa Central Community College recreation center. Midtling added a 20-pound vest to increase the difficulty of the challenge, which was a tribute to the first responders who lost their lives on 9/11.

Jack Powers, of Garner; Max Stoaks, of Clive; and Weston Johnson, of Spencer, all sophomores at Iowa Central, climbed the stairs at a fire training facility on Avenue O Friday. They climbed a single flight of stairs 110 times — representing the New York fire crews, some of whom climbed as high as 110 stories of the World Trade Center.

At about 8:30 a.m., Powers was nearly halfway to completing the 110 stories.

He was ready for a break.

“I could feel it at 20 (stories),” he said.

At 8:59 a.m., an alarm on Sanders’ phone sounded.

-Messenger photo by Chad Thompson

Iowa Central Community College fire science students work on completing 343 burpees on Friday. The number 343 represents the number of firefighters who died responding to the terrorist attack on the World Trade Center on Sept. 11, 2001.

“The south tower just collapsed,” Sanders said.

Sanders, the former assistant fire chief for the Fort Dodge Fire Department, set his phone to go off at each major event from the morning of 9/11.

Meanwhile, at the Iowa Central recreation center, about 15 fire science students were busy pushing themselves off the ground and into the air in an exercise called a burpee. They were tasked with doing 343 burpees — one for each firefighter who died responding to the attack on the World Trade Center.

Andy Midtling, an instructor and Fort Dodge firefighter, added a 20-pound vest for his workout.

Elijah Valle, of West Palm Beach, Florida, was one of the first to finish. It took him about 30 minutes to get all the burpees in.

-Messenger photo by Chad Thompson

Elijah Valle, a student in the Iowa Central Community College fire science program, performs a burpee exercise at the college’s recreation center on Friday. Fire science students completed physical challenges to memorialize first responders who lost their lives on 9/11.

“At the moment I was feeling it but once I got done felt like I could do more,” he said. “I could push a little harder. It’s a mental thing.”

Valle said he spent time living in New Jersey as a child. He feels a connection to what happened on 9/11.

“My mom was there during 9/11,” he said. “I just feel really bad for all the firefighters and people in that building. Nobody deserves to have that happen. I put them in my prayers.”

Gus Sokol, a sophomore from West Linn, Oregon, was on number 270.

“I’ve been working out on the rugby team so I’m in good shape,” Sokol said. “But each rep you have to honor it.”

Seven of Sanders’ students are on the college rugby team. Two play basketball, three are bowlers, two are sport shooters, one is involved in rodeo and another runs track.

Sanders said sports translate to being a firefighter.

“Firefighting is a team sport so it does relate well to the program,” he said. “They (rugby) are a pretty tight program. They look out for each other. Even though I’ve only had them for five weeks, they are coming together as a cohesive team. Honestly, I have a group of beasts.”

Matt Newton, an instructor and Fort Dodge firefighter, said 9/11 is a chance to help students understand the courage of first responders.

“Now, so many people getting into it were born after it happened,” Newton said. “They see pictures. This is our chance to bring attention to it and familiarize them with it and the sacrifices that came before them. These guys went out and just did it. For a lot of them, it wasn’t even their day to work.”

And while Sanders certainly honors those who perished on 9/11, he said there are people still physically suffering from the aftermath.

“One of the things we forget is there are thousands dying from the air quality issues,” Sanders said. “Respiratory illnesses and cancers from working at Ground Zero. It doesn’t get a lot of attention but it really should. Sometimes they aren’t considered line of duty but they absolutely are.”