Coaches recognize that intense training and exercising of any kind can have certain inherent risks along with the desired benefits. In general, muscles are stressed and damaged with training but are rebuilt more strongly as a result of that training (5). Injuries typically occur when athletes push beyond their physical limitations. Distance runners train intensely, often with large volumes of work, and assume these risks on a daily basis as they continually work to maintain a solid endurance base. The coaches of these runners realize that to minimize risks, preactivity warm-up and postactivity stretching is essential. A good coach must weigh the costs and benefits of training and exercise regimens to make informed decisions about the best approach for each athlete.
Research-suggested preactivity and postactivity stretching trends have changed throughout the years as new and different techniques are continually tested and evaluated (3,4,17,38). The preactivity stretching and warm-up coaches use is critical to preparing track and field distance athletes for activity, because an effective routine will reduce the incidence of injury through increased muscle temperature and compliance and also will improve performance through creating an efficiency of physiological responses (9,17,28,32,33,35). Incorrect preactivity training strategies, on the other hand, can contribute to season-ending or even career-ending injuries. Postactivity routines provide a cool-down period for the athletes, and the stretching that is preformed is designed to enhance flexibility (5). Fortunately, coach certification programs such as the United States Track and Field (USATF) program can reduce improper coaching techniques by providing coaches with safe and effective methods grounded in evidence-based research (40). The sport science component of the USATF coaches' education program was developed in association with the American Sport Education Program that was originally pioneered by a sport psychologist focused on evidence-based practice among the coached (28). Furthermore, 2 of the individuals who helped craft the sport science portion of the curriculum for the USATF coaching education program were involved in seminal research in the area of static stretching and human performance (43). The committee in charge of the curriculum for the USATF coaching education program remains dedicated to providing evidence-based practice and has recently sought out accreditation for the program through the National Council for the Accreditation of Coaching Education (41). In a similar fashion, the National Strength and Conditioning Association's (NSCA) Certified Strength and Conditioning Specialist (CSCS) Certification Program, is also designed to provide evidence-based training methods (5), and it is not uncommon for track and field coaches to obtain CSCS certification.
Current research indicates that dynamic stretching is the best form of stretching before activity and that static stretching is more appropriate after training (13,22,25). Prior studies from this research group have shown that certification does not guarantee that proper stretching techniques are followed in sports such as basketball (20), football (21), tennis (18), and volleyball (19). Therefore, the effectiveness of certification programs to educate coaches to the point that they adopt certification curriculum as their own practices is questionable. This study was conducted to examine the effectiveness of the certification and education of collegiate distance coaches in relation to their current preactivity and postactivity stretching practices with the intention of determining whether current certification programs for these coaches are promoting evidence-based stretching practices.
Experimental Approach to the Problem
The purpose of this investigation was to assess the preactivity and postactivity warm-up and stretching practices of men's National Collegiate Athletic Association (NCAA) Division I, Division II, and Division III crosscountry and track and field programs because it pertains to distance runners. The use of a survey instrument allowed for the collection of data from a representative sample of the current population. The survey instrument produced large amounts of information regarding current practices and was compared against demographic and educational classifications. These comparisons were used to understand variables that could potentially influence the alignment of coaching practices with current scientific understandings.
An e-mail detailing the study, containing informed consent documentation and a hyperlink to an online survey was sent to all NCAA men's Division l, Division ll, and Division lll cross country and track and field program participants in the United States. To avoid redundancy, only one coach per program, the head coach, or distance coach in the instance where the head track and field coach was not the distance coach, was required to complete the survey. The assumption was that the head coach would complete the survey instrument or direct the staff member responsible for stretching activities to complete the survey instrument. Current email addresses for all Division I, Division II, and Division III head crosscountry and track and field coaches were obtained from the current athletic websites of the institutions involved in the study. An introductory email explained the purpose of the study and provided a hyperlink to the institutional review board approved, web-based informed consent form and survey instrument. Data were collected during a 3-week period in February–March 2011. Early season was determined to be the best timeframe to maximize coaches' recall of stretching practices used during the current season and coaches' participation in the study. A reminder email was sent to nonrespondents 1 week after the initial email in an effort to increase the overall response rate. The institutional review board approved the present investigation, and each potential participant was encouraged to contact the principal investigator of this study to answer any questions or provide clarification before beginning the online survey instrument. Once the potential risks and benefits of their involvement were explained in the introductory email and in the introduction to the online survey instrument, the participants were informed that their completion of the survey acted as their active implied consent to the principal investigator for study participation, and that the subjects were free to withdraw their consent or discontinue the survey at any time without reprisal. Of the 770 questionnaires distributed, 111 were returned (14.4% return rate) and represent the subject pool for this study. The demographics of that subject population are detailed in Table 1.
The authors designed a survey instrument to gather demographic, professional, and educational information, and specific preactivity and postactivity practices. The survey consisted of 35 questions. The first 12 questions focused on the participants' personal and professional information, whereas the last 23 questions dealt with the preactivity and postactivity practices the coaches used with the distance runners at their institutions. Content validity was established by a group of experts. The survey was reviewed by strength and conditioning coaches for clarity and construction of the questions, and only minor editing was required to improve the clarity of the questions. Wording of the questions was designed to include descriptive information to counteract against misunderstanding of key terminology. Responses were similarly worded to maximize participant comprehension; previous research using similar questions did not reveal any difficulty with participant comprehension.
The surveys were distributed via email and the recipients were asked to complete the questions on the survey within 7 days of receiving the initial email by completing an online version of the survey using Survey Monkey, an online survey and data-collection website. A hyperlink to the survey was included in the email. Two follow-up emails were sent 2 and 4 weeks subsequent to the initial email to increase response rate. After data collection was complete, an investigation of the instrument's construct validity was performed using principal component analysis. Like items on the survey were sampled and compared for similarity in response with Kaiser-Meyer-Olkin statistics, and the results indicated (>0.600) that the instrument had construct validity.
The data were examined by computing frequency counts and means, where applicable. Results were initially computed using all responses collectively in a series of generated frequency tables, and produced “General” results. Subsequently, items of interest were compared via Pearson's Chi-square analysis to assess potential differences. Particular items of interest included the levels of coaching certification, number of years of experience, and key persons or sources of influence on the preactivity stretching activity of crosscountry/track and field distance coaches. Significance was set at alpha ≤0.05 for all analyses, and all statistical analyses were performed using JMP version 9.0.
From the 770 surveys sent to NCAA Division I, II, and III crosscountry programs, 111 coaches returned completed surveys. This represented 14.4% of the identified total population. The low response rate may have resulted from the following factors: (a) spam control software may have sorted introductory and follow-up emails into a bulk mail folder, (b) coaches may not have been interested in the topic or may not have perceived a tangible benefit from study participation, and (c) coaches may not have had sufficient time to complete the survey instrument because of the competitive or recruiting calendar (e.g., placed on “to do” list). Although the response rate is relatively low by traditional standards, review of institution and conference affiliation data suggests the sample is representative of Division I, II, and III track and field programs. Nonetheless, caution is warranted because factors may exist, which limit the generalization of study results.
The demographic characteristics (Table 1) for the participants in the investigation were as follows: n = 111, 78.2% men, 21.8% women, and age 41.31 ± 12.0 years. The respondents were primarily head coaches (60.2%) and possessed an average of 13.6 ± 10.2 years of experience coaching collegiate track and field and crosscountry athletes. All the subjects completed at least a bachelor's degree with 64% of the coaches completing a master's degree also. A large number of coaches (46.1%) did not possess a USATF track and field coaching certification nor a CSCS certification. Of the certified coaches participating, in this study, 60 reported as a USATF level I coach, 6 reported having a CSCS certification and 2 possessed an NSCA Certified Personal Trainer certification.
Preactivity Warm-Up and Stretching Practices
A vast majority (98.1%) of the respondents reported having their athletes perform a preactivity warm-up “always” or “almost always” (Table 2). Most of the respondents (85.2%) of this survey reported having their athletes perform some sort of preactivity stretching, with only 16 (14.8%) not performing any stretching. Coaches typically prescribed a combination of static and dynamic stretching activities (44.7%) or dynamic stretching activities (41.5%) before the athletic event. To a much lesser extent, coaches exclusively used a single technique such as static stretching activities (8.5%), ballistic stretching exercises (4.3%), and proprioceptive neuromuscular facilitation (PNF) stretching exercises (1.1%). Interestingly, among coaches who incorporated dynamic stretching into the group warm-up, 43.4% subsequently allowed athletes to perform static stretching independently and with assistance from the athletic trainer or the massage therapist.
Postactivity Cool-Down and Stretching Practices
Coaches indicated that their athletes either always or almost always completed a stretching regime (61.3%) or jogging cool-down (86.0%) after an athletic event (Table 3). Coaches typically used static stretching activities (52.3%) after the athletic event. To a much lesser extent, coaches used dynamic stretching (4.7%), a combination of static and dynamic stretching activities (36.3%), and PNF stretching (4.7%). Ballistic stretching was not reported as a postactivity stretching practice.
Perceived Benefits of Stretching Activities
The majority of coaches indicated that preactivity group stretching was beneficial in terms of injury prevention (77.8%) and improved performance (76.4%). Similarly, coaches indicated that postactivity group stretching was beneficial in terms of injury prevention (88.9%) and improved performance (87.7%).
Sources of Information
Another area of interest was the key sources of influence for the foundation of knowledge regarding preactivity stretching. Media, including books, videos, and online sources, was the most commonly reported source (36.1% of the total respondents) as a primary influence regarding preactivity stretching. The remaining coaches reported that coaching education was the primary influence (17.4%), followed by their former coach (high school or college) (17.2%), another distance coach (15.0%), and finally the strength and conditioning coach (14.3%).
The USA Track and Field coaching certification was another area of significant difference for preactivity stretching routines. The results of the analysis revealed 2 differences in reported stretching activities between coaches who had or had not earned a USATF Coaching Certification (Figure 1). Non-USATF certified coaches responded differently than their certified peers did, regarding preactivity stretching practices (χ2 = 21.582, p = 0.0174). Non-USATF certified coaches reported greater (χ2 = 8.49, p = 0.004) usage of static stretching alone (18.9%) vs. their certified counterparts (1.8%). The USATF Certified coaches also reported higher usage of dynamic flexibility (χ2 = 5.63, p = 0.018) during the preactivity period (92.9%) vs. non-USATF certified peers (75.7%).
Chi-square analysis revealed a difference between USATF certified and non-USATF certified coaches (Figure 2) in allowing static stretching between interval runs during practice sessions (χ2 = 11.948, p = 0.177). A higher percentage of non-USATF certified coaches (45.5%) reported allowing athletes to perform static stretches between intervals at practice than certified peers (37.9%).
A properly designed strength and conditioning program includes a strategy devoted to preparing the athlete for a specific activity. This theory is supported by this study because most (98.1%) of the coaches surveyed reported performing some sort of warm-up activity before conducting the prescribed training. These results are in-line with prior research in other sports (18–21), which revealed the following: 100% of the women's college volleyball performed a preactivity warm-up, nearly all (98.6%) of Division I and III basketball coaches surveyed performed preactivity warm-ups of some kind always or almost always, and 86.87% of Division I tennis coaches who were surveyed were compliant with research recommendations regarding preactivity warm-up. Without proper activation, the muscles needed for running cannot perform optimally, and the distance coaches we surveyed seem to be aware of this fact because of their heavy use of preactivity warm-up.
One of the primary components of proper muscle activation is stretching, and most of the track and field distance coaches (89.4%) in this study reported having their athletes perform preactivity stretching before training. Although they recognized the importance of preactivity stretching, the respondents of this study were heavily divided on the proper technique. Approximately half of the coaches (44.7%) used a combination of static and dynamic stretching in their preactivity training, whereas the other half (41.5%) had their runners perform only dynamic stretching activities before training.
In athletic settings, the term “stretching” usually connotes static stretching. A static stretch involves focusing on 1 or 2 muscle groups where the athlete reaches and holds a stretching position with minimal movement for 10–30 seconds in an effort to relax and lengthen the intended muscle group (27). Its usage by so many distance coaches suggests that they still hold on to the concept that static stretching before exercise enhances flexibility, reduces injuries, and improves performance. It has shown that gains in the range of motion and flexibility can be achieved if static stretching is performed consistently postactivity (27) but is ineffective before activity. In addition, static stretching has yet to be conclusively linked to reductions in injuries among athletes (29). In a recent review of clinical research on static stretching, 4 out of 7 studies identified static stretching as ineffective for injury prevention, whereas only 1 study supported the use of static stretching to prevent injury (37).
Research further demonstrates that preactivity static stretching does not enhance performance, and it may even be detrimental in some cases. Several studies have shown that running economy is not enhanced by acute preactivity static stretching (2,16). In another study of Bonacci et al. (8), it was discovered that no improvements to running economy were found with the use of preexercise static or with PNF stretching. Nelson et al. (30) examined the effects of chronic static stretching on running economy and found no effect, even though subjects who chronically stretched did exhibit greater ranges of motion about certain joints. Although many studies have demonstrated no changes in running economy in conjunction with static stretching, Godges et al. (15) did report a positive result in running economy related to static stretching. Beyond simply showing no benefit to static stretching and running economy, Wilson et al. (42) showed that static stretching significantly lowered endurance performance of distance runners. In their study, 16 minutes of static stretching was compared against 16 minutes of nonactivity as a warm-up, the static stretching group exhibited significantly poorer performance on a treadmill test than the no-activity group did. Hayes and Walker (16) compared multiple stretching methods (static, progressive static, and dynamic) and found no impact upon running economy or oxygen uptake but did note an increase in the range of motion.
Dynamic stretching, although similar to ballistic-style stretching, does not include the bouncing aspect of ballistic stretching, instead involves fluid muscle activity (5,46). Most often dynamic stretching consists of sport-specific movements and will increase range of motion and core temperature as the athlete moves through these positions in a dynamic manner (5). Examples include leg swings and high knees. Dynamic stretching is the most recently developed of the 4 types of stretching programs (5,46). Current research supports that dynamic flexibility is the ideal preactivity-stretching program (6,9,12,14,23,24,26,36,40,43,45).
The heavy reliance on static stretching by many of the certified coaches in this study may imply that they have not kept completely up to date on recent stretching practices research. However, as discussed later there may be other factors involved in their decision to use static stretching. Fortunately, only 9 (8.5%) of the coaches were limiting the preactivity stretching to static stretching only, the type of stretching which has been found to have negative effects on running. It is interesting to observe that 47 (43.5%) of the coaches reported that they have allowed their athletes to perform static stretching on their own or with the assistance of an athletic trainer. In addition, many distance runners have developed their own training routines including preactivity warm-ups. Distance running is a sport that requires a large amount of self-accountability on the runner's part. As such, the runner will ultimately need to be informed of research discoveries as well. Any changes in the preactivity stretching activities will need to be communicated by the coach to the runners involved to best impact both team and individual stretching activities. Therefore, allowing the athletes to design their own stretching routines that include static stretching is not in the best interest of the athlete or the program.
The usage of ballistic and PNF stretching by a few of the coaches in this study reinforces the idea that some of the participants were not current in stretching research literature. Ballistic stretching mimics the positions of static stretching; however, instead of reaching and holding the stretch, ballistic stretching involves bouncing (27). With this type of stretch, athletes reach to stretch the muscle, retract 3–6 in. and reach again creating a succession of quick bouncing movements (27). Although ballistic stretching does elevate muscle group temperature, this type of stretching trend has fallen in popularity because of its potential to cause injury and lack of muscle relaxation production. The majority of the research on ballistic stretching indicates that it should not be used preactivity (5,6,9,23,36,43). One study assessing male collegiate basketball athletes did, however, support the use of preactivity ballistic stretching (44). The PNF stretching strikes a balance between static stretching and ballistic stretching. In PNF stretching, the athlete will hold a stretching position for about 10 seconds; the athlete then contracts the stretched muscle while the partner resists. After the resistance, the athlete relaxes the muscle into a deeper stretch. Two to 3 rounds of stretch, resist, and relax are completed for each selected body part (27). Although this technique does not increase core muscle temperature, PNF is effective in creating increased range of motion (34). The PNF stretching, like static stretching, should act in a supporting role postactivity if an athlete has a particular area that needs increased range of motion (5,34).
Of the coaches surveyed, 86% revealed that they always or almost always had their athletes do some sort of light jogging to cool-down after activity. What was surprising was that only slightly more than half (61.3%) of the coaches had the athletes perform stretching of some kind. Because postactivity is the optimal time to perform the static stretching to improve flexibility (27), it would be expected that more coaches would be following evidence-based practices and would have their athletes perform stretching at that time. It is, however, encouraging that most of the coaches (90.3%) who had the athletes perform stretching included some form of static stretching in the postactivity stretching routine.
The majority of coaches indicated that preactivity group stretching was beneficial in terms of injury prevention (77.8%) and improved performance (76.4%). Similarly, coaches indicated postactivity group stretching was beneficial in terms of injury prevention (88.9%) and improved performance (87.7%). Although Daniels (11) maintained that a flexibility program could benefit the distance runner's performance, research shows no clear relationship between stretching and injury prevention (7,30,31). Thus, an important question was to find out where coaches get their information regarding preactivity and postactivity routines. The largest percentage (36.1%) reported that their source of information was the media, which included, but was not limited to, books, videos, and lay journals. With such a wide array of means to finding the information, a coach could unknowingly and easily use information that is not evidence based. However, 33.3% of coaches used coach education as their source. Unfortunately, the survey instrument used in this study did not contain questions designed to understand how coaches use the educational sources. Future and more in-depth research is needed to understand which coach education sources were cited and if these coach education sources provide evidence-based information to coaches concerning flexibility and other practices.
This study revealed a significant difference in stretching practices based on certification status. Noncertified coaches reported greater usage of static stretching alone (18.9%) than their certified counterparts (1.8%), whereas certified coaches reported higher usage of dynamic flexibility only during the preactivity period (47.4%) than their noncertified peers (32.4%). In addition, almost half of the noncertified coaches allowed athletes to stretch on their own compared with only a third of the certified coaches.
These results are in line with research conducted by Judge et al. (18) that evaluated the relationship between certification and pre and postactivity stretching practices in tennis coaches. The United States Tennis Association (USTA) High-Performance certified program did appear to influence coaches, because only 21.4% of the coaches with certification failed to follow research recommendations, whereas 50% of non-USTA High-Performance Certified Coaches did not comply. The strong resemblance of the preactivity stretching patterns among certified and noncertified distance running coaches to the earlier tennis study may be because of the nature of the athlete involved. They are both team sports but contain a very heavy individual competition component. This is supported by the fact that the results from this study are not compatible with the certification or the noncertification practices in football (21) and volleyball (19) programs that are more team oriented.
Although significant differences were revealed in this study evaluating the relationship between USATF coach certification and preactivity stretching practices, upon further investigation, a high number of coaches are still not in compliance with evidence-based practices. More than half (52.6%) of the certified coaches still did not use evidence-based practices (i.e., dynamic stretching exclusively) with their athletes as opposed to 67.6% of the noncertified coaches reporting dynamic stretching exclusively. This is where interpreting the results is critical to the conversation concerning coach certification program efficacy as it pertains specifically to preactivity; if more than half of certified coaches are not using evidence-based practices, can the assertion be made upon these findings that these programs are successfully impacting coach practice?
When using evidence-based practices for appropriate preactivity to examine the impact of coaching certification on professional practice, it is clear that not all coaches are in compliance with their physical training preactivity flexibility recommendations. The results show that although a relationship exists between coach certification and the use of evidence-based practices, there are still many certified coaches who have not adopted the dynamic stretching-only routine and are not in compliance with evidence-based practices. Given the history of research concerning certification programs (10,19,21,39) in combination with this study results, it is apparent that there is a disconnect between certification training and the perceptions and behaviors of many of the coaches who become certified.
The results of the knowledge acquisition inquiry reflected the inability of certification programs to influence coaches in pre and postactivity training decisions primarily because of competition with media outlets, which are not regulated to promote evidence-based practices. Coach education programs fell a far second from media outlets and just barely ranked ahead of past coaches, another distance coach, and a strength and conditioning coach as the primary source of knowledge when distance coaches make preactivity and postactivity stretching decisions. It would appear that although certification programs provide coaches with evidence-based information they choose to ignore it or do not stay current once they receive certification. It is possible that they choose to consult other outlets such as media or other practising professionals, such as distance or strength coaches, instead of the coach certification program curriculum, because it is less scientific in nature and easier to understand. Another factor might be peer pressure, in that none of their colleagues follow evidence-based recommendations or they are required to follow the directions of a head coach. Unfortunately, the survey did not contain questions that would indicate why they chose the information source they used.
In reviewing these findings, it should be noted that the study is not without limitations as generalizations from this study are difficult because of the sample size. Self-reported questionnaires and limited comparable data create difficulty in assessing result reliability (1). Survey research has limitations: answers may be intentionally false as the subjects questioned may not wish to reveal their true practices, even if anonymity and confidentiality are guaranteed by the investigators. Thus, these results should be interpreted with caution.
The results of this study suggest that it is necessary for crosscountry and track and field distance coaches to reevaluate their own practices, perhaps crosschecking them with current research results. It is apparent that a coach cannot solely rely on past practices that have been handed down by previous coaches, especially when it comes to the flexibility programs of their crosscountry and distance teams. The availability of coaching certification courses provided by the USATF is a useful resource in allowing coaches to find the most pertinent information about running practices. Certification programs that are grounded in research principles, such as the NSCA's CSCS Certification Program, stress the importance of staying current in research trends, and how to apply that knowledge on the field. Therefore, crosscountry and track and field distance coaches at all levels could benefit from participating in certification programs like the system offered by the NSCA to keep up to date with current practices or at least work with strength coaches who have NSCA certification. By getting involved in these coaching education-certification programs, a coach can tap a valuable resource regarding the most current evidence-based practices in the field of distance running. Certification and training courses using evidence-based practices must continue to challenge common misconceptions of traditional lines of thought. However, if a coach is to improve the coaching practices of his or her program, he or she must not only attend the coach education courses but should also adapt these principles as practice and refer to them consistently throughout their tenure as coach. This may mean reenrolling in coach education courses or keeping certification study tools close at hand. The USATF coach's education program along with coaches should take measures to account for the disparity between education and practice. The results of this study are also important for strength and conditioning coaches who work with crosscountry and track and field distance runners. It is unlikely that the strength and conditioning coach will conduct the preactivity warm-up and stretching routine for distance runners on a daily basis, but they should advise crosscountry and track and field distance coaches to develop a pre and postactivity protocol that is in line with the current research.
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