The Brazilian striker's first season England was plagued by injury, but he has been fully fit for the start of this summer's preseason.
“I’m feeling very good, very strong, very different to how I felt last year," said the 24-year-old to the Bees website. "I’ve never felt better.
“I've probably had to do a little bit more work than the other players over the summer but I’ve also wanted to relax my head and not focus just on football.
“My goals are very specific and personal to me, but the main thing is that I want to be in the best possible form, the best possible shape to do what Brentford hired me to do – and that’s score goals.
"I want to be in the best possible form, the best possible shape to do what Brentford hired me to do – and that’s score goals"
On new manager Keith Andrews, Thiago is upbeat.
He added, "It’s a different mentality and a different way to work. It’s good because we can learn different ways of thinking and different ways of playing.
“The main difference has been the work with the ball. Instead of just focusing on the running, we’ve been working with the ball and on the more technical side of things."