This adaptation can be both good and bad, and the good and bad aspects are flipsides of a coin. On the “good” side, your body will adapt to stress by becoming fitter, stronger, faster, etc. On the “bad” side, your body will adapt to weaknesses/injury by compensating around the problem; the normal biomechanical chain will be interrupted and circumvented in order to avoid stressing an area that is damaged. Of course, these two manifestations of physiological/neuromuscular adaptation both play a huge role in training. Fitness can easily mask a dysfunction, because you can indeed get fitter and faster while compensating. Conversely, a compensation pattern that taxes a smaller muscle may in fact overwhelm gains in fitness, either by limiting your ability to train or by pain which causes you to back off on intensity.
Both of these adaptations are really quite extraordinary, and it shows how versatile your body is. However, in order to get the most out of your body, you need to think about each one. The brain is a huge tool in overcoming compensation patterns, as it is what you need to use to fix bad technique or to retrain muscles to work appropriately. Cues, drills, and forced activities that require proper mechanics (swimming with paddles or the band, high cadence cycling, etc.) all require a massive neurological commitment. Training your brain in this sense is also important for racing, as becoming “stupid” during a race is one of the primary reasons for poor technique later in a race, assuming you are not running low on calories. My own feeling is that this is a major reason why caffeine is so helpful during races, because it stimulates your brain, which allows you to focus on technique.
Because fitness can serve as such a great cover (at least for a while) about how your body is compensating, that underscores the importance of getting “unfit” in the offseason. This can often magnify biomechanical problems when you return to training. You also have more time to “think” during lower volume training, which makes this time of year great for working on proprioceptive issues.
Finding the right people to help you is invaluable. With some proper guidance, I’ve finally started to resolve things I was simply resolved to endure. It’s a great feeling.