Getting into shape really isn’t as mysterious as it seems.  An entire marketing industry has pushed the idea that you need expert advice and expensive diet plans to drop a few pounds, but the reality of the mechanism is really pretty simple: burn more calories than you take in, and the rounder parts of your body will eventually begin to square off.  Admittedly though, if your goals are more complex than simply losing weight, your methodology will have to grow a bit more complex to match.

If you played sports in high school or college, or have worked with a personal trainer at some point in your life, you’ve likely already heard about the difference between working to develop fast twitch muscle fiber versus slow twitch muscle fiber.  This simplistic breakdown of muscular training may not be the most biologically accurate depiction of how the process of getting stronger works, but it does serve as a great way to depict the paradoxical nature of functional fitness: the more you work to get better at one thing, the worse you’ll become at some others.

Fast twitch muscle fiber is the sort of muscle professional football players tend to pack on.  Big, powerful muscles that are good for unleashing explosive bouts of force, followed by a long recovery period, are perfect for a sport like football, where you work your ass off for 7-10 seconds at a time, then take a 40-second break.  People who develop a great deal of fast twitch muscle fiber without working to develop muscular and cardiovascular endurance, are often pretty intimidating, but have a tendency to run out of gas pretty quickly.

Those who devote their training to developing slow twitch muscle fiber, on the other hand, develop more of a lean, runner’s build.  These folks can keep moving for extended periods of time, while exerting limited amounts of force.  Slow twitch muscle fiber lends itself, above all else, to endurance, making it perfect for the guy or girl that’s got a lot of ground to cover on foot, but a poor choice for body builders.