Kane has had several layoffs in the past due to his ankle problems but has been injury-free this season. He also suffered a hamstring injury while playing for Tottenham Hotspur in 2020 that kept him on the sidelines for two months.
The striker said he has been working with the physiotherapist for three years and that he is in a "totally different place" now.
"I was struggling to play consistently throughout a season," Kane told reporters on Thursday.
"Especially when you come up to major tournaments, it's great to know your body is in a good place.
"You can get injured at any moment, whether it's a tackle or a bad movement, but I think when you're free in your mind and you've been playing consistently for a while, it definitely helps with your mindset.
"I kept getting ankle injuries and that led to a bigger hamstring injury. As I've got older and more mature, you learn more about your body. When you can push and when you should not push too hard. That's helped me to consistently play at the level I have."
England, who have two losses and two draws from their four Nations League group matches so far, play Italy in Milan later on Friday and host Germany at Wembley on September 26.
