Based on the reposts and Facebook comments, it seems that I'm not the only one who is impressed by Navy SEAL David Goggins, so here's some more. It's worth noting that while Mr. Goggins is clearly an impressive physical specimen, for me what sets him apart is his mental strength. In this video he says two things that really resonate with me. "If you can see yourself doing something you can do it. If you can't see yourself doing something, usually you can't achieve it" and "when you think that you are done, you're only 40% in to what your body is capable of doing. And thats just the limits that we put [on] ourselves."
While I spent a lot of time studying human physiology, it's worth noting that most of time when we think our body can't do more, it's actually our brain that holds us back. There are many examples in a lab setting. In one study, cyclists were asked to pedal at threshold until volitional exhaustion. When they said they were done, the researchers told them to sprint (above threshold pace) for a short time. And they did it. In other words, when they said they couldn't go on, they were actually able to not only maintain their pace, but they were able to accelerate.
And there are examples in real life as well of people doing "superhuman" things when faced with dangerous situations. Of course just as Mr. Goggins dealt with stress fractures, urinating blood, and other physical consequences of his endeavors, the woman who lifts her car because her baby is trapped under it usually rips her tendons off the bone, but what's noteworthy is that if you had asked her one minute before the emergency, she might have told you that she's weak and unable to lift her groceries, let alone her car.
The body is powerful, but the brain is even more powerful.