Started lifting weights at 15 for football, and never stopped, 40 is not old when it comes to staying in shape.
Older Guys Can Still Make Gains
University of Oklahoma researchers compared people of different ages who followed the exact same program for eight weeks. They found that guys between 35 and 50 years old built just as much muscle as those between 18 and 22 years old. DEXA (duel-energy x-ray absorptiometry) scans showed that the college-aged men gained around two pounds of muscle, while the middle-aged men put on 2.5 pounds of muscle. Moreover, strength gains in both the bench press (7 pounds for the college-aged men and 14 pounds for the middle-aged men) and leg press (55 pounds for the college-aged men and 40 pounds for the middle-aged men) were similar in both groups.
Seriously doubt a guy like Tom Brady thinks he needs any help from drugs.