Most of the newer periodization systemsthose introduced since 1980are nonlinear. One example is the so-called multipace training method developed by David Martin and Peter Coe. In their book Better Training for Distance Runners, Martin and Coe write: One sensible method for injury-free performance progress over the course of a macrocycle involves harmonious interdevelopment of strength, speed, stamina, and endurance all during the year, never eliminating any of these from the overall training plan.
We tend to disagree with coaches who prescribe large volumes of solely longer-distance running over an initial period of weeks, followed by a similarly concentrated bolus of solely higher-intensity speed sessions over succeeding weeks. There are three major criticisms of linear periodization systems, two of which are alluded to in this quotation.
First, many coaches and athletes with experience of such systems believe that the sudden introduction of high-intensity running after a strictly low-intensity base phase carries a high risk of injury. Second, the various important aspects of running fitness are not developed harmoniously. Why devote several weeks to developing strength only to let this attribute slide again by replacing strength workouts with speed work? Third, linear periodization systems require months of buildup for a rather brief opportunity to race at the very end.