A recent Ball State alumnus and his boyfriend broke a Guinness World Record with 355 selfies in an hour.

Alumnus Mark E. Miller took approximately one selfie with a different stranger every 10 seconds for an hour May 3. Miller had help from Indiana University student Ethan Hethcote for the task completed as part of #MissionSmile.

#MissionSmile, a movement dedicated to making the nation smile, contacted Miller and Hethcote after noticing the couple’s popular lifestyle vlogs on YouTube.

Selfie World Record

355 selfies in an hour

Approximately one selfie per 10 seconds

Guinness World Records rules stated each photo had to be with a different stranger

“Ethan and I loved the idea of getting people to smile and do random acts of kindness and posting them to social media sites with the #MissionSmile,” Miller said.

To spread the word, #MissionSmile sent Miller and Hethcote to Miami’s South Beach to take more than 50 selfies with strangers, which was the previous record.

“I’d be lying if I said it was easy,” Miller said. “Fifteen minutes in, I was covered in sweat and nearly out of breath. The Miami heat didn’t help but overall, it was an unforgettable experience.”

Guinness World Records rules stated he couldn’t take more than one photo with the same person. Miller said to speed up the process, #MissionSmile crew members spoke to beachgoers to sign waivers before Miller approached them for a selfie.

“There were a few shocked beachgoers who wanted nothing to do with us,” he said.

At the end of the hour, they had 355 selfies to show.

“It’s rewarding to know so many people were behind Ethan and I and would love to participate in something like this again,” Miller said.

Earning a certificate for the record-breaking task meant Miller missed walking for a different piece of paper. The telecommunications graduate couldn’t make it to Spring Commencement.

“This was an opportunity that we couldn’t pass up,” he said. “Attempting to secure the Selfie World Record sounded silly, but the main reason we said yes was to spread the positive movement. ... [My family] understood this event would help gain exposure for our YouTube channels.”

Miller said he and Hethcote plan to continue documenting travels and their lives on YouTube because it makes them both happy.

“We would love to continue making videos and normalizing homosexuality for our generation and generations to come,” Miller said.

The couple chose a good city for breaking the record. Miami is the world’s third most selfie-obsessed city, according to a map by TIME. In the Florida city, there are about 155 selfie-takers per 100,000 people.

Indianapolis, which has a nearly tripled population than Miami, ranked 311 with eight selfie-takers per 100,000 people.

Raymond Garcia contributed to this article.