Why such a long training time?
Batman can't really afford to lose. Losing means death—or at least not being able to be Batman anymore. But another benchmark is having enough skill and experience to defend himself without killing anyone. Because that's part of his credo. It would be much easier to fight somebody if you could incapacitate them with extreme force. Punching somebody in the throat could be a lethal blow. That's pretty easy to do.
But if you're thinking about something that doesn't result in lethal force, that's more tricky. It's really hard for people to get their heads around, I think. To be that good, to not actually lethally injure anyone, requires an extremely high level of skill that would take maybe 15 to 18 years to accumulate.
Where does that number of 15 to 18 years come from?
That comes from my own training in martial arts and seeing how long it takes people to respond to simple situations—let alone the complexities of smoke bombs going off and people having big Batsuits on. No matter how much training you have, when we're subjected to a lot of psychological stress, we make a bunch more mistakes. The police talk about this when they use things called reality-based training. It takes years and years and years and years to have the poise to be able to perform when somebody is attacking you for real.
What's a realistic training regimen?
I didn't give a training manual in my book, but he'd want to do specialized weight training to build up an ability to work at a really high rate for maybe 30 seconds to a minute (the maximum time period associated with his fights). One of the early comics shows him holding an enormous weight over his head. That's not the right kind of adaptation toward punching and kicking. He's got to make sure he's doing all the skill training at the same time so that he's actually using the (physical) adaptations he's slowly gaining. In conventional martial arts, when people take weapons training, you're doing a kind of power-strength training.
What effects would all that training have on Bruce Wayne's body?
I looked up what DC Comics and some other books said (about Batman's physique). I settled on the estimate that Bruce Wayne started off at about six-foot-two and 185 pounds. I gave him a body fat of 20 percent (slightly below average) and a body mass index of 26. Let's say after 10 or 15 years, after he's become the Batman, he's weighing about 210 pounds and has a body fat of 10 percent. He's probably gained 40 pounds of muscle. His bones will actually be more dense, kind of the opposite of osteoporosis.
Are we talking freakishly dense bones?
The percentage change is actually quite small—maybe 10 percent. In judo, where people do a lot of grappling and throwing, you're going to have more density in the long bones of the trunk. In karate and other martial arts where they're doing a lot of kicking, there's going to be a lot higher density in the legs. Muay Thai (kickboxing) is a great example. They're always doing these low shin kicks. They try to condition the body by kicking progressively harder objects and for longer.
What about his reaction speed?
There is evidence that experts in something like football or hockey have an improved ability to perceive movement in time. In the book I use the example of Steve Nash throwing the ball, even though he can't see where the receiver of the pass is going to be. Experts are able to extract more information faster than others. It's almost like their nervous systems become more efficient.