SANTEE, California (Feb. 22, 2016) -- Staff Sgt. John Nunn overcame the flu to win the 2016 U.S. Olympic Team Trials for the 50-kilometer Race Walk to earn his third Olympic berth with a personal-best time of 4 hours, 3 minutes and 21 seconds on Feb. 21.

Nunn said the day before the race his body temperature topped 100, coupled with body chills, aches and burning eyes.

"I remember lying in bed, tears were coming down," he said, "and I was thinking, 'I have worked so hard for this. I have devoted so much time and effort, and the Army has backed me. This can't end this way.'"

Having attained the 4:06:00 Olympic "A" standard when he won the 2015 U.S. 50K Race Walk National Championship with a 4:03:42 clocking in November, Nunn called USA Track & Field officials Saturday to see if he could start the race on Sunday morning, drop out, and still be named to the 2016 U.S. Olympic Team.

"They said 'You have to finish. This is not a question,'" Nunn recalled. "We're sorry you feel this way, but you have to finish.'"

Nunn was on the starting line Sunday for a 7:15 a.m. start to a 31-mile race in which one foot always must be in contact with the ground.

Nunn is a Soldier in the U.S. Army World Class Athlete Program, or WCAP, a detachment of the U.S. Army Installation Management Command's Family and Morale, Welfare and Recreation division. The program allows Soldiers - Active, Guard and Reserve - an opportunity to train full time in an Olympic sport, and participate in the Pan American Games, World Championships, Olympic and Paralympic games while maintaining a professional military career and promoting the U.S. Army to the world.

"It definitely was a race where knowing that I had the support of the Army was a huge factor that helped pull me through," Nunn said. "I was like, 'You know what? I know I'm sick, but we're going to go take care of this now.'"

Before the race began, Nunn explained to civilian training partner Nick Christie that he had the flu and would attempt to walk with him for 30 kilometers to help Christie obtain the Olympic qualifying standard, but then he likely would slow down and simply try to finish.

As it turned out, the race went exactly opposite.

Nunn, 38, and Christie, 24, walked side-by-side for the first 28 of 40 laps around the 1.25-kilometer circuit. They were both on pace to hit the Olympic standard. On Lap 29, Christie surged about five meters ahead of Nunn, but not for long. When Nunn retook the lead one lap later, Christie dropped off the pace and finished a distant second in 4:22:31 -- 16 minutes off the standard.

"The first 25K was so hard," Nunn said. "Everybody was saying that I looked so relaxed, but my stomach was hurting so bad."

By the 30K mark, Nunn said his body "went numb."

At that point, he and Christie had lapped the field three times, so he told himself "If you end up passing out, stop to throw up, or your body crashes, you can still pull second," Nunn recalled.

Christie, on the other hand, had nothing left.

"Everything looked good, and all of a sudden it's what happens in 50K and marathon: the body just gave out and I crashed badly," Christie said.

Nunn sensed finishing the 50K was within his reach, and decided no flu or stomach bug was going to stop him.

"I started pushing it," Nunn recalled. "And when Nick fell off of me, I felt really bad for him. I was hoping he would stay with me for another 10K or so and then let adrenaline take over for the last five laps and get the standard, but he fell off and I ended up lapping him."

Nunn lapped Christie a second time during the final 15 kilometers. By then, with victory and a third Olympic berth virtually in hand, the Soldier-athlete needed another source of inspiration.

It came from U.S. Army World Class Athlete Program Chief Willie Wilson, a retired command sergeant major who has supported Nunn throughout most of his Army career, cheering Nunn on from the sidelines.

"I heard him say something to the effect of 'the unit's behind you and the Army's proud of you,'" recalled Nunn, whose gait grew stronger as the race grew shorter. "He said Soldiers would be excited to know what was about to happen."

"It put things very much in perspective," Nunn said. "This is so much bigger than just me. I'm not out here racing for some [small-time] sponsor that I convinced them to let me do it. This is the United States Army and they believe in me enough that they've invested time and money and emotion and other people into this."

Wilson saw on Saturday that Nunn "was really struggling with stomach problems and temperature -- very flu-like symptoms."

"But he showed up on Sunday, still not feeling the best, but determined to give it his all by representing the Army, IMCOM and the World Class Athlete Program as a professional Soldier," Wilson said. "He had a phenomenal performance. He persevered and worked through struggling with cramps and pain. What an example of resiliency."

Wilson sensed that Nunn knew he was walking for something larger than himself.

"I think he took his situation and refocused off of the pain and problems that he was having and started focusing on (1) wanting to represent the Army and the United States at the Olympic Games in Rio, and (2) he realized that he was out there for something a little bigger than just Sergeant Nunn."

In the end, Nunn walked his fastest time ever.

"I remember rounding the back turn on the last lap," Nunn recalled. "I looked down at my watch and I was walking faster than what I had been going, and I was like 'Man, you can get a personal best -- just go get it.'

"Yeah, I freaked out Saturday," Nunn said. "But when the race started, it was 'Okay, it's time for business. I don't care how you feel or what's going on, you have to do everything that you can to make sure this goes right.'"