Felipe Nasr has said he is prepared if a mid-season opportunity arises in Formula 1 and also expressed his concern about Brazil's legacy in the sport.
Nasr has been linked as a potential replacement for Jolyon Palmer at Renault, with the Brit under pressure after a poor start to the season.
And Nasr has revealed that he has been working hard in the gym in order to ensure that he his capable of driving the new, physically-demanding cars.
"I'm ready now if I have to jump in a Formula 1 car tomorrow," Nasr said via Autosport.
"I've gained nearly three kilos of lean muscle, as I was planning to do."
"My manager has been on top of this [potential return to Formula 1].
"He has been speaking to teams. It's just a question of time.
"There is a lot of commercial interest behind it and you have to put things together."
Nasr is also worried about Brazil's decline in Formula 1, with Rubens Barrichello the last Brazilian to win a Grand Prix in 2009.
"Of course it's a concern," he added.
"I'm also concerned for the younger generation because Brazil has such a part in the history of Formula 1.
"We just cannot let the legacy go. I'm pretty sure the country sees it that way.
"We shouldn't stop finding new drivers to come up."