Jozy Altidore appears to have spent some time in the gym. After scoring a great goal versus Costa Rica, Altidore ripped off his jersey to celebrate and showed just how strong he's become. I don't recall Altidore being that big and strong.
Jozy's celebration could be called, "do you even lift bro". However, in the modern game of soccer, it's the skinny soccer player who is usually the best player on the field, whether that's Neymar or Iniesta. But for forward's like Jozy or say Manchester United's Romelu Lukaku, being big and strong helps you as a hold up forward keep possession and fight of defenders.
Yes, Altidore was never skinny, but it seems Jozy has been doing some curls and bench press or some kind of weight lifting routine. He's now like the Incredible Hulk, accept not green and just scores big goals.