Many parents know the thrill and the agony of watching their children compete in sporting events. Parents of 10-year-old soccer players roam the sidelines, shouting praise. Some fathers (and mothers, too) make fools of themselves at community league games. Parents of high school players sit in the stands, aching when their child makes a mistake, glowing when he or she excels.  A relative few watch their offspring perform on television, praying they don’t get hurt.

As long as your child competes, those feelings persist. Recently I sat in front of a computer to track my daughter’s progress in an Ironman triathlon. I couldn’t see her, but I “watched” for 15 hours, experiencing all the emotions that sweep over parents who actually witness their children’s efforts.

My daughter, Kathleen, was competing in Ironman Florida, held in Panama City, where she would have to swim 2.4 miles, bicycle 112 miles and then run a 26-mile marathon — all in 17 hours or less.

Kathleen is 49. She has been competing in triathlons for almost five years. The Florida event was her second Ironman. She finished Ironman Arizona last year in 16 hours and 17 minutes. She trained hard for Florida nd expected to do better.

Participants in these events may rent a GPS device they attach to their clothing. It sends a signal that becomes an icon on a website. As fathers (and others) watch, the icon moves with agonizing slowness along a map of the bike and marathon routes.  A legend provides essential data about time, distance and pace.

THUS I FOUND myself on a recent Saturday morning watching a tiny pyramid on two wheels labeled “Kathleen Kellams” move away from the start of the bicycle portion of the race.

I could see that my daughter was not doing well.

She was already behind her Arizona time for the swim, which shocked me, because it had taken her 20 minutes in Arizona to recover from the frigid lake waters. Now, in Florida, she had lost precious minutes.

What I didn’t know was that she had suffered seasickness in the choppy waters of the Gulf of Mexico, swallowed lots of salt water and spent long periods clinging to a bobbing kayak as she dry heaved and retched into the waves. (Rules permit contestants to use a kayak for support, as long as the kayak doesn’t move.)

Leaving the kayak, she floated for a while on her back, staring at the sky to take her mind off the sickening sight of the buoys rising and falling in the swell. Three times more she felt so sick she had to stop and hold onto a kayak or surfboard.

Had I known that, and been there, what would I have said? Give up? Tough it out?

Kathleen reached shore after two hours in the ocean.

Now dehydrated and nauseous, she began her bike ride. This was her best event, and I thought she could make up some of the time lost in the water. I watched her icon creep in millimeters along the course. She was averaging more than 17 miles per hour, better than her Arizona pace. My hopes rose.

AT HER PACE, a 112-mile ride was going to take more than six hours. It gave me time to reflect on how she had come to be an Ironman.

She was not a gifted athlete as a child, but was always exposed to sports and physical activity. I taught her to swim when she was very young. When she was older she loved doing flips on a trampoline.

In third grade, she was assigned to play first base in softball. She enjoyed this position because it gave her the opportunity to gossip with the base runners. At that age, if a batter could hit the ball, she was assured of getting to first base safely, and Kathleen welcomed all visitors.

In high school, she refused to remove her earrings when she played goalie in field hockey, but in one game she held her opponents scoreless and her teammates carried her off the field on their shoulders.

As a camp counselor, she served as lifeguard and swimming instructor, an experience that helped her land a job as waterfront director at a Club Med resort.

As a social services worker in Florida, she coached a softball team composed of people with Down syndrome.

She was a good skier, but didn’t like the cold.

Later, living in Colorado, she battled against weight gain by working out almost daily, taking spinning classes or group weight training. She also forced herself to run for miles, even though she was very slow.

In 2008, she received an invitation to enter a sprint triathlon, which requires a swim of just under a half mile, a bike ride of 12 miles and a run of 5.1 miles. Intrigued, she decided to enter.

To prepare, she joined a women’s training group. Here she found a community of friends and supporters. As the months passed, she entered more races, competing with her pals. She liked being part of the group.

Gradually, the challenges increased. She tried Olympic triathlons, then half-Ironmans. She went on 100-mile bike rides, ran in half marathons. She trained all year long.

Then, three years into her triathlon career, she made the big leap to Ironman Arizona.

MEANWHILE, back in Florida, Kathleen’s pace on the bike was slowing. I watched as her average speed dropped back to the Arizona standard, then fell below it. I urged her mentally to kick it up a notch.

But she only went slower. Although I didn’t know it, she was suffering in the 83-degree heat and high humidity. A steady headwind off the ocean didn’t help. She had to stop at every aid station to try to rehydrate and cool off. She gulped water, poured quarts of it over her head and then got back on her bike.

When she completed the bike portion she was 45 minutes off her Arizona standard. I thought she could not finish the race under the 17-hour deadline. She would have to complete the marathon faster than she did in Arizona, and running was by far her weakest event.

If she couldn’t finish the swim and bike sections faster than a year earlier, I thought, how could she possibly do it in the run?

I figured she would have to set a pace of less than 16 minutes per mile to make it, and she had averaged 16.3 mpm in Arizona.

Out on the course, Kathleen made the same calculation. She also found that she could not run at all. Her plan had been to mix walking with running, but as she started to jog she became nauseous.

“I realized I was going to have to walk the entire course,” she told me later, “And I was going to have to speed walk.”

AS I WATCHED on the computer, now caught up in the ordeal and almost certain she wouldn’t make it, I saw that her average pace was slowing from an encouraging 14.3 minutes per mile to a still satisfactory 15.1 mpm.

I began to calculate her possible finishing time, and saw that she could make it with a little time to spare — if she could maintain the pace I thought she was achieving by running part of the way.

But she was only walking, as fast as she could, and the pace slowed even more, to about 15.4 mpm. And there it stayed, mile after mile after mile.

It was now night in Florida. She wore a light strapped to her head to illuminate the route. She had begun the day with pre-race preparations at 5:00 a.m. The swim started at first light, 7:00 a.m.

It was often lonely on the walk. Once she took a wrong turn, but someone shouted at her and she retraced her steps and got back on course.

She occasionally chatted with fellow stragglers. “If I stop, I’ll collapse,” a man told her when she asked how he was doing. She felt like quitting. Mentally, she cursed the ocean, her bike, the very street beneath her feet.

Kathleen pressed on. Her legs were growing stiff and painful, and she could feel a blister developing on the sole of her right foot. To compensate, she changed her stride, landing on her heels. She went on.

WHEN SHE HAD less than a mile to go and only about 30 minutes before the deadline, I switched to another website that provided a live video stream from the finish line.

I watched as the late finishers straggled home to the cheers of the crowd. The announcer greeted all finishers, male and female alike, by shouting out their names and proclaiming, “You ARE an Ironman.” The crowd cheered each one.

But there was no sign of Kathleen. She wouldn’t give up now, I knew that, but I feared she might have fallen, twisted her ankle or been overcome with nausea.

As the big clock above the finish line ticked away toward midnight, I began to panic. Where was she? I switched back to the tracking website. It said she was three-tenths of a mile from the finish line.

I switched back to the live video. Where was she? A man in advanced middle age finished. Then came two women running as a pair. Another woman jogged across and appeared to collapse. I tried to peer down the course as far as the floodlights permitted.

I saw nothing. Then I heard the announcer, “And here she comes, from Highlands Ranch, Colorado ...” With that, I started yelling, “Way to go, Kath! Way to go! You did it!”

I kept yelling at the computer screen as she emerged from the dark, jogged across the finish line and threw up her arms in the winner’s pose. She looked terrible.

She had been on the course for 16 hours, 47 minutes and 4 seconds, and was sick most of the time. She was among the last to finish in a field of 2,430 racers. But she was an Ironman, twice an Ironman actually, and I was one happy dad.

“I will never swim in the ocean again,” vowed Kathleen after the race.

A few days later, I asked her how she felt about her performance. She said that although her times were slower than Arizona, she was prouder of her Florida effort.

“It showed I was pretty tough,” she said.

EDITOR'S NOTE: Dan Kellams is a graduate of Marion High School and the author of “A Coach’s Life: Les Hipple and the Marion Indians.” He lives in Connecticut.