This past weekend I was lucky enough to witness two world class performances based on “residual fitness”. Even if one of the performances was from an athlete with less that 4 years of high-level training, and the other was from a veteran in the sport, both of them overcame less than perfect build-ups towards their race in order to perform well.
The term “residual fitness” can be a little misleading, since it might lead us to believe that even if your preparation was far from perfect, you still have a little something left in the tank. However, we should call it not-so-residual fitness, or just plain fitness.
Fitness is the weighted sum of all the training adaptations an athlete collected EVER. Of course that the catch is that time is the variable that weighs in the sum, and that whenever an athlete stops training, a relatively rapid loss of the acquired adaptations starts to occur. For example, half the increase in mitochondria from 5 weeks of training can be lost in one week of inactivity. Since the number of mitochondria is substantially related to the endurance capacity of an athlete, it is obvious that one week of inactivity will have a marked effect on endurance. It is required nearly 4 weeks of training in order to recover from one week of inactivity. However, coaching experience throughout the years have taught us that the rate of detraining of the endurance capacity depends on the time that has been spent in building up this capacity. Or in other words, the more time an athlete spends building up his fitness, the longer his fitness will be mantained, even if he/she drastically reduces training. Another consequence of the fact that fitness is a function of time is that the training an athlete does in the last 6-8 weeks is the most important do determine his/her current fitness. But all the training an athlete did before those last 6-8 weeks is of paramount importance, as it determines your fitness entering this period. And that is the residual fitness.
There are many practical implications of what was stated above. The first one underlines the importance that consistency has in the training process. Consistency over weeks, months and years is what brings your residual fitness up, guaranteeing long-term development. Even if your fitness peaks a few times a year, residual fitness determines the starting point from which racing fitness will rise. The second implication is that when approaching a race with a less than perfect final build-up, an (extra) effort to stay focused on the big picture should be made. As long as the training period preceding a period of inactivity due to injury, illness or life was continuous and long enough, there is no reason to panic. The athlete will be able to regain his/her level of fitness in a short time. Residual fitness will carry you on race day, as long as you gear your last weeks before race week to tap into it.