This is an excerpt from Developing Endurance by NSCA -National Strength & Conditioning Association & Ben Reuter.
For endurance athletes, the normal progression of fitness begins by developing a good aerobic base (see figure 3.1). Overdistance (OV) and endurance (EN) training are used to build the base of the aerobic system. This is followed by more high-aerobic and tempo work (moving up the pyramid). Then lactate threshold and maximal effort sessions (top of the pyramid) are added when the body has built up a strong foundation of aerobic fitness and strength.
A normal distribution outlining the volume, intensity, and percentage of each type of training during each progression can be seen in table 3.1. As noted, aerobic conditioning (indicated as overdistance and endurance) is a major portion of training year-round. Speed work (indicated as lactate threshold and V?O2max) is a smaller but very important component of training that helps athletes improve their performance. The information in table 3.1 can be used as a guide for planning the volume, intensity, and relative contributions of each area shown in figure 3.1.
Two types of periodization are commonly used by endurance athletes: traditional and inverse. Both types can be implemented using a standard or reverse method. In traditional periodization, the athlete progresses through the typical cycles of preparatory (base), precompetition (build or intensity), competition (race), and transition (off-season). For athletes who compete in events, a short tapering phase is generally used before competition. (See Tapering and Peaking later in this chapter.)
Figure 3.2 presents an example of the standard method of building volume and intensity within a traditional plan. The example depicts a 3-week build that should be followed by a 1-week recovery cycle. This strategy is usually best for novice and intermediate endurance athletes who have less than 7 years experience in the sport. The athlete is able to slowly build volume and intensity over 3 weeks. Note that a standard 3:1 build-to-recover progression is merely an example of the many ways to periodize a training program. This method could lead to high fatigue during the third week if the athlete is not ready for the load or if the athlete has a lot of outside stressors that influence recovery.
The reverse method, as its name implies, begins with a higher load and gradually decreases through the cycle (as shown in figure 3.3 on page 50). Athletes who have 7 or more years of experience in the sport can typically handle this type of progression. Because the training load is highest in the first week of training, this strategy is more demanding and should only be used by advanced athletes. This method can provide great benefits because the athlete engages in the highest training load after a recovery week, so the body is more rested. The athlete can more easily attain a higher volume and intensity of training because the accumulated fatigue is not as great as it is when using the standard method of progression.
The second popular type of periodization, inverse, begins the training year with an emphasis on strength and technique. The athlete then progresses to focusing on speed and strength, followed by aerobic power and economy. Finally, before the competitive season, the athlete shifts to focusing on aerobic capacity. The two methods of progression—standard and reverse—still apply. Because of the higher speed and the strength training component in the beginning of the training year, athletes should be experienced in their sport and have well-established cardiovascular fitness before beginning this method. This method of progression improves the athlete's strength and speed earlier in the year and allows the aerobic component to be shortened and implemented just before the race season.
As mentioned previously, a periodization mesocycle can be planned in many ways. The traditional 3:1 build-to-recover cycle is popular but is not recommended for all athletes (as explained earlier). Other potential build-to-recover models—such as 2 weeks to 1 week, 16 days to 5 days, or 23 days to 5 days—can be implemented with great success. The 2:1 cycle is especially good for novice endurance athletes because it allows for good recovery in the beginning of a training program. Keep in mind that any single approach to training may not work throughout the entire season. For an athlete to continue progressing toward optimal performance, various training methods may need to be used throughout the athlete's training year. Once the athlete's body begins to develop and the athlete's performance begins to level off, it may be time to change the periodization method or look at the recovery program in more detail.
Learn more about Developing Endurance.