^ except all Spartans are injected with a special drug that you can only handle once your body is in a certain physical condition. This drug enhances you in every physical way. This includes increased muscle build in your legs, increasing running speed and jump height. And also, great muscle buildup in your arms, increasing bicep and tricep strength considerably. Hence why he can flip 3 times his weight. Which, honestly, isn't to much. I mean, I'm twelve, weighing in at nearly 130 pounds, and I can flip a 400 pound tire in my hockey fitness practices. So I dont see how a fully grown man, drugged to physically enhance himself, can't flip 3 times his weight. Besides. A tank is a LOT more than 3 times chief's weight.