A Christian Guide to Body Stewardship, Diet and Exercise

Chapter 5: Training for Endurance 104 individuals (Peterson & Rittenhouse, 2019). Some of the factors that influence exercise economy include neuromuscular coordination, muscle fiber type, joint stability, and flexibility (Training 4 Endurance, 2017). Recommendations for improving exercise economy include regular participation in drills aimed at improving overall run technique (e.g., skipping, bounding, double and single-leg hops, sprinting). Other recommendations include lower body resistance and plyometric training, especially single-leg exercises (e.g., Bulgarian split squats, lunges), as well as exercises aimed at strengthening the torso (e.g., plank, side plank, back hyperextensions). Muscle fiber type is another, albeit small, factor that can influence endurance performance. Individuals with higher percentages of slow-twitch (type I) muscle fibers tend to perform better at slower, longer endurance events (e.g., 5-km, 10-km, ½ marathon, marathon); whereas individuals with higher percentages of fast-twitch (type II) muscle fibers tend to perform better at faster, shorter endurance events (e.g., 100-m, 200-m, 400-m, 800-m). Although the majority of slow-twitch muscle fibers seem to be set at birth, a small percentage of fast-twitch fibers can become more aerobic in nature with chronic endurance training (a process called fiber type transition). Figure 5.2 depicts the differences in muscle fiber type percentages for long, middle, and short distance endurance athletes. The red cells represent slow-twitch (type I) muscle fibers; whereas, the white cells represent fast-twitch (type II) muscle fibers. Figure 5.2. Fiber Type Differences between Endurance Athletes