Why Workouts Work for Humans, Not Pickups
Space Daily began an article on space medicine with a thought-provoking comparison:
Most machines don’t improve with use. Old pickup trucks don’t gradually become Ferraris just by driving them fast, and a pocket calculator won’t change into a supercomputer by crunching lots of numbers. The human body is different. As weightlifters know, the more that people use their muscles, the stronger they become. And unused muscles do not remain preserved; neglect causes them to waste away, or atrophy.
It’s a remarkable response, one that scientists don’t fully understand. Somehow, muscle cells “sense” how they’re being used and then remodel themselves to better fit the task. How does this happen? And what exactly is it about exercise that triggers the changes?
The rest of the article, written by Patrick L. Barry, delves into how space physiologists are working to improve the exercise programs used by astronauts. They are striving to understand muscle response at the genetic and molecular level.
Muscles respond to stress by growing stronger because of programming. Our genes have billions of lines of code, and each cell is equipped with exquisite environmental sensors and molecular machines that carry out the instructions for repair and growth (read about just one example, among thousands, on EurekAlert).
In addition, the genetic code is programmed to regulate itself and produce more (or less) machinery and construction material depending on the signals received from the environment: the food and oxygen coming in, the temperature, the stress and much more. Pumping that bicep with a dumbbell sets off a cascade of signals and cellular activity that each respond to internal instructions, resulting in a better-prepared muscle for next time. The fact that this doesn’t happen with pickup trucks, pocket calculators and rocks should remind us all of the power of intelligent design to overcome the otherwise degenerative nature of the second law of thermodynamics, at least locally and temporarily. Why not illustrate this comparison by driving to the gym or a hiking trail today? Have a good workout, and remember, “no pain, no gain” applies to your body, not your car.