The video game "Counter-Strike" plays out on their monitors as they communicate over headsets, engaged in a fierce competition at Moscow's IgroMir Expo, Russia's largest computer and video game convention.

But this is not your average group of gamers. The slogan on their black jackets reads "We've got time to kill."

With an average age of 67, the Silver Snipers from Stockholm, Sweden, are the oldest esports team in the world.

"We want to win, so we have to train a lot," said team member Inger Grotteblad, 66, nicknamed "Trigger Finger." But she doesn't mind. "The team is so close to each other. We know each other very well."

Sponsored by tech company Lenovo, the five Silver Snipers travel across Europe for "Counter-Strike" tournaments, playing against teams from around the globe. They train in Stockholm with their coach, 38-year-old Tommy "Potti" Ingemarsson, a 10-time "Counter-Strike" world champion.

Last fall's world tour, their first, also included stops in Paris and Finland. Grotteblad hopes the team can score invitations to upcoming competitions in South America.

Esports is "a lovely community to be in," Grotteblad said, adding that before she started playing, she thought it was young guys sitting at home, playing games all night long.

But she and the team found something unexpected: a welcoming community and a loyal legion of fans to cheer them on.

"It's very lovely ... because you could be treated like 'go away,' " she said. "Instead, they are opening their arms for us and saying, 'Oh, you're so cool!' My grandsons say, 'You are the coolest grandmother in the world!' "

The esports community is just one benefit for these senior gamers. The social engagement with each other is good for their health, too. Grotteblad's has formed a close friendship with teammate Monica Idenfors, 62, nicknamed "Teen Slayer."

It might sound simple, but happiness and fun are proven to have measurable impacts on our health and longevity. One study found that older people were up to 35% less likely to die during the five-year research period if they reported feeling happy, excited and content on a typical day.

On top of that, concentrating on the game keeps their minds active. The brain forms new neural connections, an ability known as neuroplasticity, that could help slow some of the mental effects of aging.

"The brain can improve itself by being challenged," said Dr. Adam Gazzaley, a neuroscientist at the University of California, San Francisco, where his team explores the way our brains interact with video games, even building games that are designed to target certain areas of the brain.

"The basic idea is to use a video game that engages a player in an immersive way, which we think is critical, and challenging them appropriately to their ability," he said. Then, using an algorithm designed by his team, "we can activate selective brain networks through this experience and because the brain is plastic, including the brain of seniors, improve the function over time."

The Silver Snipers prepare to compete in Russia.

When it comes to the older population in his gaming studies, Gazzaley has noticed a heightened level of enthusiasm. "In our experience, it makes them excited and optimistic that they can engage in technology -- and get good at it."

With the Silver Snipers, Grotteblad has noticed a personal change, too.

"I keep my brain alert," she said. "It's a big difference. I keep my hands very, very alert too, because you have to be rapid in your movements with your hands. You have to coordinate what you're doing without thinking what you're doing."

Still, moderation is important when it comes to video games.

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"These [games] are designed to be really enjoyable and sticky," Gazzaley said. "Human nature, in many ways, is to find something you enjoy and just keep doing it, but I do believe you have to fight against those habit-forming activities and find diversity. Moderation is the main thing."

For the Silver Snipers, it's all about creating a balance while improving focus, keeping their brains active, being social and having fun; in many ways, they are gaming their way to longer lives.

"When I look in the mirror, I see all the wrinkles," Grotteblad said, "but I don't feel old. I feel like I've always been. Sometimes, I can feel like I'm 25 when I'm laughing too much!"