The streaming lifestyle, like that of some other stationary professions, “intuitively and medically seems such an unwise way to spend one’s years,” said Dr. James A. Levine, a professor of medicine at the Mayo Clinic who studies obesity and is the author of “Get Up! Why Your Chair Is Killing You and What You Can Do About It.” The upshot may be health problems including cardiovascular disease and diabetes, he said.

Twitch’s community guidelines bar destructive behavior, without directly addressing what some perceive as excessively long periods of playing. In an email, a Twitch spokesman said of Mr. Vigneault that “we are greatly saddened about the passing of one of the Twitch community.”

Wargaming, the company that makes World of Tanks, wrote in an email that it was “saddened to hear of the loss of streamer and tanker Brian Vigneault.”

Ben Bowman, 30, a professional Twitch streamer with more than 579,000 followers, published an article on the video game website Polygon in January about the pressure to stream constantly, which he said in an interview could lead to exhaustion, high cholesterol and heart problems. He said he had developed a herniated disk from sitting for hours each day with no breaks because he wanted to attract the biggest audience possible on Twitch.

“As a business thing, doing a 24-hour stream allows you to stretch the widest net,” Mr. Bowman said. “There’s a cultural understanding that you have to be on eight to 12 hours a day with no breaks. I used my channel like that and that took a really massive toll on me.”

Soon after Mr. Vigneault’s death, Joe Marino, 45, who has more than 40,000 followers on Twitch, wrote an article on Medium about the emergency heart surgery he had in 2015. In an interview, he said his relentless streaming schedule — at least seven or eight hours a day, seven days a week — led to the surgery, an experience from which he is still recovering.