"This is the first time I've been part of the race," the Hagerstown man said. "It's cold. But I felt a need to be out here."
Rosette was among dozens of volunteers who offered supplies and shouts of encouragement to participants in this year's ultramarathon.
Like Rosette, many people had a special reason for lending a hand, including 10 people from Greencastle, Pa., who worked the Donnie Oberholzer Memorial Water Spot in Downsville.
"Donnie was an avid runner who raced in the JFK," Rich Secrest said. "He passed away several years ago, so we thought this would be a nice way of remembering him."
Secrest is head coach of the cross country team at Greencastle-Antrim High School and director of the Greencastle Flyers, a road running, cross country and track and field club for area youths.
"I didn't know Donnie personally, but I know about his special dedication to fitness and young people," he said. "This is a small way of saluting that commitment."
Secrest was joined by members of his high school cross country team and Flyers club.
This is the third year that the group has volunteered for the JFK ultramarathon, he said.
"We really enjoy it. You meet people from all walks of life," he said. "It's also so neat to see how much the runners appreciate us being out here."
Of all of the things a teenager could be doing on a Saturday morning, standing in freezing temperatures along the towpath would be pretty far down the list.
But on Saturday, 14-year-old Jordan Jensen was doing just that - and enjoying every moment.
Jordan was among a group of volunteers from Young Life Washington County, a youth ministry organization from Clear Spring.
"I wasn't feeling very well this morning, but I didn't want to miss it," Jordan said. "I've done this before and really enjoy it."
Jordan said it's a good feeling volunteering for the race.
"The runners are so thankful for what we do," she said.
The Young Life group was responsible for the mile 42 aid station on Dam 4 Road along the towpath.
"We have about 20 young people who volunteered," said Kimberly Jensen, whose husband, Brian, is director of Young Life.
The Cumberland Valley Athletic Club provides most of the supplies, she said, "but we added some extra items, including peanut butter and jelly sandwiches."
Young Life has participated in the JFK 50 Mile ultramarathon for the past several years, Kimberly Jensen said.
"It's fun because we're stationed at the end of the towpath and we can give them encouragement with only about eight more miles to go to the finish line," she said.
Among those waiting at the finish line at Springfield Middle School was Eric Seifarth of Hagerstown, who came to cheer on several friends who were runners.
In past years, Seifarth said he has raced in the JFK, but this year he was an observer.
"It's a tough course, and guys like me have to be sensible," he said. "I have to go to work on Monday."
Still, Seifarth said he missed being a participant this year.
"It's different standing and watching," he said. "Plus, I've never been at the finish line with daylight. Usually, it's getting dark."