Dr Charles Czeisler advises golfers to get as much as nine hours of sleep, reports The New York Times.

“It’s amazing to me how many people kind of know how important sleep is for performance and still make choices that negatively impact their ability to get the proper amount,” Winter said.

He added: “In 10 years, people who do what I do will be a dime a dozen in sports. The reason it’s fun now is you can use it to your advantage because most people don’t even think about it. I like the idea of being able to ingrain in somebody starting out that you can get your sleep together and you’ll be able to beat people who are better than you.”