Coaching Youth Middle Distance Runners: Training
Middle Distance Runners
Among the works written about the subject of training young middle distance runners, Loprinzi et al. (2012) summarize the subject well. From their conclusions:
We suggest that, when feasible, coaches individualize and employ periodization into their runner’s training regimen. Additionally, it may be beneficial to limit the intensity and frequency of training in the off-season and, to assess for overtraining, evaluate the runner's motivation and mood levels, as well as morning heart rate. To reduce the likelihood of injury, coaches should employ a systematic training regimen and runners are encouraged to develop their core strength and wear appropriate running shoes. (p. 35)
Most important among these tenets is the principle of individuality: "Training should be directed and tailored to the individual, taking into account the strengths and weaknesses and how these weaknesses can be addressed as development proceeds" (Kennedy et al., 2005, p. 42). Coaches should also be aware of the different responses to training that younger runners may have compared to more mature athletes. While children are trainable, they may not develop as an adult would in similar training conditions (Bar-Or, 2012; Lemura et al., 1999). Additionally, their bodies do not adjust to warmer temperatures as well as those of adults, and thus may need more time to acclimatize (Armstrong et al., 1996).
Intensity and VolumeEdit
A strong debate exists between the proponents of various training philosophies advocating either high-intensity, low-volume or high-volume, low-intensity training programs (Enoksen et al., 2011; Helgerud et al., 2007; Seiler & Tønnessen, 2009). In their review of the literature in this area, Nielsen et al. (2012) found no definite correlation between running-related injuries and the volume, duration, intensity, and frequency of training. That said, more training—either through increased intensity or volume—is not necessarily better. A study from Garcin et al. (2002) found that highly trained athletes' physiological characteristics did not improve after adopting a more difficult interval training regimen, and their rating of perceived exertion (RPE) for equivalent work loads actually increased over that time. Nor is long, slow distance necessarily advisable: "in order to prevent overloading of the metatarsals in adolescent runners, excessive mileage at jogging pace should be avoided" (Fourchet et al., 2012, p. 685). Coaches often strive to achieve a balance between the two approaches (Laursen, 2010), but the primary purpose of this work is to provide practical advice for coaches for the administration of young athletes' training programs, not to advocate specific training philosophies.
Tapering is the process by which an athlete reduces his or her training load for a period of time prior to an important competition in order to improve performance. A taper that reduces volume—but not intensity—is an effective tool for improving race performance (Mujika, 2010; Mujika & Padilla, 2003). In a meta-analysis of the literature regarding the tapering process for athletes, Bosquet et al. (2007) concluded that "a two-week taper during which training volume is exponentially reduced by 41–60% seems to be the most efficient strategy to maximize performance gains" (p. 1364). Even a three-week reduction in training has been shown to have no negative effect on endurance training adaptations (Houmard et al., 1990).
Although almost every coach mandates that his or her athletes perform a warm-up routine prior to practices and competition, few understand the scientific basis for such an activity. Warming up may help to avoid next-day soreness (Law & Herbert, 2007), but the literature regarding warm-ups and stretching does not indicate that they lead to a reduction in injuries (Thacker et al., 2004; van Mechelen et al., 1993). Static stretching, i.e. reaching down to touch the toes, is not an effective warm-up technique. In fact, static stretching prior to a race may actually increase the energy cost of running and thus hurt performance (Wilson et al., 2010). Although performing dynamic stretches, i.e. high knees, may not improve elite runners' race performance (Wunderlich, 2012; Zourdos et al., 2012), they are a much more effective warm-up protocol than static stretching for young athletes (Faigenbaum et al., 2005) and distance runners in general (Leon et al., 2012). Regarding stride-outs, i.e. short runs of increasing speed and intensity, performed as part of a warm-up routine, Ingham et al. (2013) showed that running two 50 m stride-outs followed by a 200 m run at race pace as a warm-up improved 800 m time trial performance more than running six 50 m stride-outs.
Middle distance running is a relatively inexpensive sport; however, there are many misconceptions regarding the few pieces of equipment required to participate. Products can be purchased as needed, but most will have little or no real impact on performance. Athletes may feel that they prefer a product even when it provides no real benefits. In a study comparing conventional socks to the fitted socks often sold at running specialty stores, Purvis and Tunstall (2004) found that the subjects preferred the specialty socks; however, they produced no physiological advantage and the runners still described the conventional sock as comfortable. Ali et al. (2010) found a similar "comfort only" effect with compression socks, made popular by professional athletes like Paula Radcliffe, although Kemmler et al. (2009) did find that they significantly improved running performance. Lower body compression garments may improve some physiological measurements, but have not been shown to improve performance (Dascombe et al., 2011). Manufacturers often advertise clothing made of synthetic material as some kind of aid for sweat evaporation, but there is no evidence to suggest that these garments aid thermoregulation or comfort during exercise (Gavin, 2003). Treadmills should only be used as a last resort for training. In their study, LaCaille, Masters, and Heath (2004) found that
the treadmill setting was rated as least satisfying, while resulting in the highest RPE and slowest performance time. Alternately, the outdoor route resulted in the highest levels of positive engagement, revitalization, tranquillity, and course satisfaction, while also yielding the lowest levels of physical exhaustion and RPE. (p. 461)
Training shoes can significantly alter adolescent runners' biomechanics (Mullen & Toby, 2013), but athletes are often misled by marketing approaches. Running shoes are often sold as a way to either increase comfort or avoid injury, yet there is no valid evidence to justify manufacturers' practice of focusing on pronation control or cushioning (Richards et al., 2009). Enke et al. (2009) found that almost three fourths of the adolescent cross country runners they surveyed claimed that arch type was most important factor when buying running shoes, but only a little more than one half knew their own arch type; this lack of self-knowledge holds true for recreational runners in general (Hohmann et al., 2012). Athletes should wear what feels comfortable for them, not what costs more. Clinghan et al. (2008) found that "low- and medium-cost running shoes in each of the three brands tested provided the same (if not better) cushioning of plantar pressure as high-cost running shoes" (p. 189). One notable exception to this rule may apply if similar styles are available as models for both children and adults. Forrest et al. (2012) found that these versions differed sharply in their composition and kinematic effects, even among the same size. They recommend using the adult version when available.
Although significantly different from true barefoot running (Bonacci et al., 2013), the use of so-called "minimalist" running shoes has attracted attention from some researchers, primarily because runners who prefer such footwear may be more likely to use a forefoot strike pattern—that is, they hit the ground with the ball of the foot first, followed by the heel (Goss & Gross, 2012). Some researchers have associated this pattern with a reduced risk of overuse injury (Daoud et al., 2012), but the use of minimalist footwear has not yet been shown to have a corrective effect on habitual rearfoot strikers (TenBroek et al., 2013), and can pose a risk for bone injury (Ridge et al., 2013). According to a review of the literature by Goble et al. (2013), "current evidence is insufficient to indicate that barefoot runners are faster, perform better, or are any less prone to injury than shod runners who prefer a heel‐striking gait" (p. 53). As suggested by Nigg and Enders (2013), "the important aspects of performance and/or injuries are more related to (a) individual preference and (b) individual running style, independent on whether the athlete runs in shoes or barefoot" (p. 6). In some cases, customized shoe orthoses may improve the comfort levels of athletes with chronic injuries (Hirschmüller et al., 2011).
Supplementary and Alternative TrainingEdit
Specificity is an important part of a training program: Cross-training programs involving activities such as biking or swimming, for example, are not as effective at improving performance as a specific running program (Foster et al., 1995). Middle distance runners may still benefit from other forms of training, however:
- Sport-specific resistance and strength training such as plyometric exercise can improve anaerobic performance without any significant negative effects on aerobic performance (Mikkola et al., 2006; Sedano et al., 2013; Yamamoto et al., 2008).
- The use of a periodized core training program can benefit runners (Fredericson & Moore, 2005).
- Balance training programs can significantly reduce the incidence of ankle sprains, a common running injury (McGuine & Keene, 2006).
As with all other aspects of the sport, differences exist between genders on the approach to and the effects of middle distance training. For example, females' kinematic responses to competition footwear, such as racing flats or spikes, differs significantly from males' (Logan et al., 2010). Most notably, younger female runners at are at a higher risk of overuse injury than males (Rauh et al., 2000). In terms of acute injuries, boys are more likely to suffer from pelvic issues, while girls are more likely to sustain ankle injuries (Reid et al., 2012). Stress fractures, one of the most common chronic issues affecting runners, are influenced by different factors for male and female runners:
Multivariate regression identified four independent risk factors for stress fractures in girls: prior fracture, BMI [Body Mass Index] <19, late menarche (age menarche ≥15 years), and previous participation in gymnastics or dance. For boys, prior fracture and increased number of seasons were associated with an increased rate of stress fractures, whereas prior participation in basketball was associated with a decreased risk of stress fractures. (Tenforde et al., 2013, p. 1843)
It is also important to note that contrary to popular belief, "intensive endurance training during childhood and adolescence does not influence size attained and rate of growth in stature and body mass" (Eisenmann & Malina, 2002, p. 168); importantly, this holds true for female runners as well (Baxter-Jones et al., 2002). Some female runners may perceive strength training in a negative light as a physique-changing activity—they want to avoid the "ripped" look—but it is important to note that
implementing a vigorous strength training program in previously untrained (strength) female distance runners may yield positive results in running economy. Upper and lower body strength improvements are evident and expected in a program of this type. Also, this improved strength is not associated with significant changes in body composition. The improvement in running economy would be significant for a competitive distance runner. It could shave vital seconds off her time and it is these seconds that determine a runner's placement in a race. (Johnson et al., 1997, p. 228)
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