Variance refers to the natural undulation in a training program with regard to duration of effort, movements, and loading. There are infinite levels that you could go to in playing around with variance:
- working out in the heat or the cold
- at altitude or at sea level
- listening to AC/DC or in dead silence
But the major factors that will influence intensity and ultimately fitness are not that complicated.
CrossFit says that “routine is the enemy”. Segmented training, or just doing one routine will produce segmented results. If you only go long and light, you will likely struggle with fast and heavy. If you only lift heavy, you will likely suffer in a 10k run. If you don’t try to combine some of those things together, you will be very surprised at how a little wrinkle in the program can completely defeat you.
Coach Greg Glassman, the owner and founder of CrossFit, once told the story of a state police officer who had earned the title of the “Fittest Officer in the State”. This officer had run a mile in 5 minutes and also had a 400lb bench press, two very impressive feats of fitness. So Glassman trained this fellow and made a deal with him to highlight where the gaps in his training might be. He said that he could use those 2 movements he excelled in, running and bench press. Yet instead of running a mile and then doing a max bench, he would make the officer only run 400 meters and only bench press 135lb for 21 reps (certainly nothing for a guy with a 400lb max). This workout would be 7 rounds for time.
The officer was shocked when he found himself walking in the workout and quit at round 5. So what happened to the “Fittest Officer in the State”?
Remember: Routine is the enemy.
If you are always doing the same thing, you are writing a road map to where you are going to fail, even if things only change a little. Diversity, adaptability, versatility across a broad spectrum of tasks creates real fitness not just specialty in a few choice things. As CrossFit says “Our specialty is not specializing”.