The Brazilian veteran sat out the Hungarian grand prix recently with an illness that caused dizziness.
But already last weekend, the 36-year-old posted on Instagram a photo of himself out running with his trainer.
And now, as Massa holidays in his native Sao Paulo, he has revealed he has been lapping at speed on the kart track at Interlagos.
“Great feeling getting back on track!” he said. “I feel good.”
Sure, yes. I’m really in good shape – Massa says about his F1 future
Formula 1 veteran, Massa is saying that he can continue in Formula 1 next season – states “no reason” to close his F1 career.
When asked if him staying on was dependent on there being a good opportunity, Massa told Motorsport.com: “Sure, yes. I’m really in good shape, the way I’m driving, the way I understand the car and everything.
“I have no reason not to stay in F1, but we’ll see what’s going to happen.