On my walk early this morning, I noticed that I was breathing a little more deeply as I walked up the hill behind the chapel. It made me realize how incredibly intricate our bodies are. My muscles have to work harder when I’m climbing, so they need more oxygen. My lungs and hearts respond immediately without my even thinking about it. My breathing becomes deeper and the air exchange in my lungs goes up more than tenfold. My heart also begins beating faster and more vigorously, increasing the blood flow to my lungs and muscles over tenfold. The net result is that I’m extracting ten times as much oxygen per minute from the air, and my circulatory system quickly delivers this much-needed oxygen to my hard-working leg muscles. It also picks up the excess carbon-dioxide being generated in the muscles and off-loads this into the lungs which promptly exhales it into the air. All this simultaneous and synchronous activity not only takes marvelous care of the body’s needs, but it also keeps the body’s delicate acid-base system in perfect balance. We are indeed fearfully and wonderfully made!
