The program is designed to take someone from sitting on the couch to being able to complete a 5k (3.1-mile run) by using interval runs and is quite effective. It's one of the tools I used to go from sitting on the couch to completing three Tough Mudders, extreme endurance 12-mile (20k) long muddy obstacle runs.
The thing I love about this technique is that you can use it to get good at virtually anything.
What is an Interval Run
In case you aren't a serious runner, I should probably define what an interval run is. An interval run is where you alternate running and walking for specified periods. For example, the first interval run on the C25K program lasts for 30 minutes. You warm-up with a five-minute walk, alternate 60 seconds of jogging and 90 seconds of walking for twenty minutes, then cool down with another five-minute walk.
Why It's Effective
The beauty of interval runs is that when you use them consistently, they will create muscle, which allows you to run longer and faster. Even Olympic level athletes use these, as not only can you run longer, but you can push yourself much harder when you're only running a short period
Done right, you're gasping by the end of each short run, or if you're my dog interval running with me while I try to impress my wife, you're puking (oops, sorry Marbles).
It's the equivalent of lifting heavy weights a handful of times before you exhaust yourself rather than grabbing a lighter weight and lifting it fifty times in a row.
How it Applies Outside of Running
You can use this same technique outside of running. Think back to times your finances did exceptionally well, for example. You likely got intense for a brief period, then lapsed. If you were more intentional about that, you could build up to being a financial superstar by saying something like this month I'm going to save and invest 50% of my income. You can do anything for 30 days, right? Repeat that enough times, and it'll become more natural.
If you want to be a writer, try writing every day for thirty days. Or maybe write for an extended period of time at least four times a week. If you wish to be a better painter, try painting every day for thirty days.
I think you get the idea. Get intense for a while; give yourself a break, then do it again. Do that enough times, and you will get good at nearly anything you put your mind to.