Some people have black hair, some have blonde hair, and some have no hair. Some are tall, some are short. Some have dark skin, some have light skin. Some are bow-legged, others are knock-kneed. While the hardware may look different, the operating software (OS) is quite similar among us. The human body has built-in survival programs—it’s programmed to move, breathe, take in food for energy, and gain or lose fat depending on the circumstances.
The Sprint for Survival
Imagine being chased by a lion, a bear, or any other predator that could rip you apart at will. You’d run like hell to save your life. In 30 seconds or less, your fate would be decided. If you survived, your body would register the experience and adjust its OS accordingly. The new program would read something like this: Get lean and fast so that next time you can escape.
Our ancestors encoded that data long ago. That’s why, when you engage in short bursts of all-out effort—like sprinting or high-intensity interval training (HIIT)—your body taps into that ancient survival program and responds accordingly: Get lean and fast!
The Endurance Trade-Off
There’s another survival program at play as well. Historically, humans were nomadic, traveling long distances in search of better living conditions. To make these long treks easier, the body adapted by shedding excess muscle (which is metabolically expensive to maintain) and storing more fat (which serves as a long-term energy reserve). The updated OS for these conditions reads: Store less muscle and more fat.
So, if you engage in slow, steady-state cardio at low to moderate intensity for prolonged periods, your body runs that old endurance program. The result? Get small and fat!
Adapt or Crash
The body is a highly adaptable organism—our survival depends on it. But if you repeatedly try to override its programming with ineffective methods, eventually the system will crash.
Take-Home Message
If you’ve been doing endless aerobic exercise in the so-called “fat-burning zone” but can’t seem to lose body fat, it’s time to load a different program. Try high-intensity interval training and see how your body responds. If you survive, it just might be the key to getting lean and fast!
