SPEAKER_02 33:18–35:51
Some of this is going to be theoretical, so it might be interesting to some of you. And then the rest of you, you just turn it off. It's okay. I'm only expecting about five or six views on this one. So we're going to dig into some theoretical first. And this comes from Ryan. Ryan says, You said that the ability to expand and compress and expand again is a universal principle. Can you give a handful of examples in the human body outside of gait or shoulder and hip range motion? And also, can you name some examples in the natural world and the universe? I warned you. Okay. This is actually a fun question for me because I do like to kind of talk about some of this stuff. But Ryan, one of the things you have to recognize is that everything about you is a compression and expansion. So let's just look at your heart. And I think everybody has a representation in their head when they're looking at a heart beating. They understand that blood flows into the heart, it expands, it compresses, and then the blood flows out. And by the way, the heart doesn't pump it out. That's a different story. But everything inside of you is going to be based on compression expansion. So the peristalsis that moves the lunch through your gut is compression expansion. If we look at something local, like muscular contraction so if I concentrically oriented muscle there's actually a higher pressure within that muscle so the intra muscular pressure is higher as we reduce the concentric orientation we have a reduction in in pressure there as well so again we always have compression expansion taking place somewhere at some time. We're also going to see this as global strategies. So every movement that you have is going to have some peak moment of force output, which will be representative of the compressive strategy to what degree is then dependent on what you're doing. If you're drinking a glass of water, it's not going to be your maximum peak force that you could produce, but there is going to be a peak in that moment in time. If I'm doing a vertical job, it's a little bit easier to see that representation of that peak moment. So again, so every sporting movement is going to have this expansion to compression, to expansion representation. If we're talking about a high jump, the moment that the high jumper plants his foot into the ground, there's gonna be a peak resultant, and then as he leaves the ground, he's gonna re-expand. Sprinter, same thing, hitting the ground, compression to expansion. If I'm throwing a baseball, there's a moment in time where everything squeezes tight. Time stops and I produce this maximum output of force. It's just very, very brief and so we don't see these things because our eyes just can't stop time to recognize that. But we can see these things. We can measure these things in force plates and we can watch it on video and such. So Ryan, everything becomes this compression to expansion to compression. If we look at the universal principles, if you will, we can get really off the deep end here. And we can say that, okay, spacetime has a very specific shape that looks like that. And that's called a light cone because light behaves the same way, time behaves the same way, space, the influence of gravity, et cetera, all play into this sort of expansion, compression, expansion. If you were, if you're theoretically near a black hole, you would probably recognize this shape as well. So again, this is all theoretical physics stuff, which is way above my pay grade. But anyway, it makes us a nice representation when we talk about our external rotation and internal rotation representations of how we move.
compression-expansion principleintra-muscular pressureforce production mechanicstheoretical physics in movement