African Journal for Physical, Health Education, Recreation and Dance (AJPHERD) December 2012 (Supplement 1:2), pp. 309-320.
The relationship between psychological factors and the number of injuries sustained by elite male African youth soccer players JULIUS JOOSTE, SUZANNE JACOBS AND LINDA VAN DEN BERG Department of Sport, Rehabilitation and Dental Sciences, Staatsartilerie Road, Pretoria West Campus, Tshwane University of Technology, Private Bag X680, Pretoria, 0001, Republic of South Africa; E-mail:
[email protected]
Abstract Review of literature indicates that information regarding the psychological factors associated with injury occurrence in young elite sport participants is limited and incomplete. The aim of this study was to examine the relationship between specific psychological factors and the prevalence of injuries among elite youth male soccer players. One hundred and forty-nine elite, male African national soccer players from 11 African countries participated in this study. The participants completed a self-administered questionnaire adapted from Twizere (2004) to report the injuries sustained over a two-season period. Psychological factors were measured with the use of the Competitive Anxiety Inventory-2 (Martens et al., 1990); Athletic Coping Skills Inventory-28 (ACSI-28) (Smith et al., 1995), and Bull’s Mental Skills Questionnaire (Bull et al., 1996). Results revealed a positive relationship between the soccer players’ cognitive anxiety scores and the number injuries they have recorded (CSAI-2). No relationship between any of the coping skills and injuries was revealed (ACSI-28). It was, however, indicated on the Bull’s Mental Skills Questionnaire that better relaxation ability is associated with reduced risk of injury occurrence. Even though the psychological data were collected during an international soccer tournament which could have affected the participants’ general responses, the study still provides useful insight on particular psychological factors that contribute to the occurrence of injuries amongst elite youth soccer players. The study recommends that relaxation skills in attempt to regulate cognitive anxiety should be considered in youth soccer injury prevention programmes. For a comprehensive understanding on the role psychological factors play in injuries among elite youth athletes, one should evaluate their individual perspective and interpretation of their stress-coping mechanisms along with other contributing stressful life events. Keywords: Psychological factors, injuries, youth African soccer players. How to cite this article: Jooste, J., Jacobs, S. & van den Berg, L. (2012). The relationship between psychological factors and the number of injuries sustained by elite male African youth soccer players. African Journal for Physical, Health Education, Recreation and Dance, December (Supplement 1:2), 309-320.
Introduction Soccer is the most popular sport in the world, played by men and women, children and adults with different levels of expertise (Reilly, Williams, Nevil & Franks 2000; Stølen, Chamari, Castagna & Wisloff, 2005). Participation in soccer is an effective way for children to increase their level of physical activity and fitness, because it requires intensive physical effort over an extended period of time through competition and training (American Academy of Pediatrics,
310 Jooste, Jacobs and van den Berg 2000). The American Academy of Pediatrics (2000) estimates the growth in pediatric soccer participation in the United States as 11.4% to 21.8% annually. As in physical activity, as participation in soccer increases so does the number of people at risk for injury (Junge, Cheung, Edwards & Dvorak, 2004; Leininger, Knox & Comstock, 2007; Kerr, Collins, Fields & Comstock, 2011). Elite soccer players are exposed to many hours of training and competition every week, and are, therefore, under enormous physical and psychological pressure (Devantier, 2012). Interest in the epidemiology of sport injuries has led to the general conclusion that two major factors influence the occurrence of injury namely, external risk factors (e.g. type of sport, playing surface) and internal factors (e.g. physiological and psychological) (Dvorak, Junge, Chormiak, Graf-Baumann, Peterson, Rösch & Hodgson, 2000; Johnson & Ivarsson, 2011). A number of models have been created which emphasise a relationship between psychological risk factors and injury occurrence (Ivarsson & Johnson, 2010). The most influential was Williams and Andersen’s (1998) “stress-injury model” which proposes to divide psychological risk factors into three main categories: personality factors, history of stressors, and coping resources. Athletes with high competitive anxiety, many life events, and low coping resources may, when placed in stressful situation, exhibit considerable stress responses. As a result these athletes can be placed at higher risk of injury than athletes with opposite profiles. According to Johnson and Ivarsson (2011), personality can affect what situation an athlete apprehends as stressful. Furthermore, Pedersen (2007) stressed a association between perceived injury risk and aggregate aggression. For example, a dysfunctional psycho-physiological process may affect an athlete’s risks of being injured. Some examples include disturbance of attention, high or low arousal and poor muscle coordination (Johnson & Ivarsson, 2011). Several studies indicated a positive association between sport injuries and high stress levels (Patterson, Smith & Everett, 1998; Maddison & Prapavessis, 2005). Williams and Andersen (1998) stress injury model has proved itself as a feasible foundation for understanding the interrelated role social and psychological factors have on the occurrence of sport injury. A substantial amount of research supports this approach (Devantier, 2012). However, many studies are often based on university-age athletes at the individual sport level. Therefore, it is important for the advancement of the field to include additional studies on younger athletes, especially those at elite level, as they are exposed to more hours of training and competition. The main focus of the present study was to investigate whether specific psychological factors affect the number of injuries among elite, male youth soccer players.
The relationship between psychological factors and number of injuries 311 Methodology Study Design A cross-sectional, quantitative study design was used in this study as the participants’ prevalence of injuries and psychological qualities were evaluated. Participants The study was conducted on 149 elite, male African soccer players aged 14 to 18 years with a mean age of 16.2±1.13 years. The players were drawn from eleven African countries which included Botswana, Kenya, Malawi, Namibia, Nigeria, South Africa, Tanzania, Uganda, Zambia, Zimbabwe and ECABU (Invitational team sent by the East- and Central Africa Business Unit). The data were collected during the 2010 COPA Coca Cola youth soccer tournament hosted by South Africa in which all the participants competed. Test procedure The investigation was approved by the organisers in charge of the 2010 Copa Coca-Cola tournament in a formal agreement with the Department of Sport, Rehabilitation and Dental Sciences, Tshwane University of Technology. Information that explained the purpose and details of the aim of the study was provided to each player. Thereafter consent was obtained from each participant as well as their team coach/manager. Consensus on the purpose of the study and confidentiality of each individual player were ensured. Coaches could, if requested, get access to their team’s overall results and not individual players’ results for the purpose of reducing the effect of socially desirable answers from participants and to limit the influence it could have on team selection processes. Participants were informed that they were free to withdraw from the study at any stage. Data were gathered by means of a once off group administration of the questionnaire per team under the guidance of the researcher. Injury data Injury data were collected retrospectively and included prevalence of injuries over a two-season period (2008/2009 and 2009/2010). A self-administered questionnaire adapted from Twizere (2004) was used to collect the injury data for this study. The questionnaire has two parts. The first part sought descriptive information about the soccer players such as race, division, years experience, team name, age as well as the played position. The second part requested information on the history of injury, which included the number of injuries sustained and the severity (time loss), body parts affected and mechanism of injury. Injuries were reported separately for training and competition. The definition of injury prevalence adopted in this study was “sustaining at least one injury either in training or in competitive sessions”. This definition of injury prevalence was also used by various other researchers (Twizere, 2004;
312 Jooste, Jacobs and van den Berg Nematswerani & Mars, 2005; Azubuike & Okojie, 2009; Mtshali, MbamboKekana, Stewart & Musenge, 2009). Psychological evaluation Various sport psychological skills were measured by using the Competitive Anxiety Inventory -2 (CSAI-2) (Martens, Vealey & Bump, 1990); Athletic Coping Skills Inventory-28 (ACSI-28) (Smith, Schutz, Smoll & Ptacek, 1995) and Bull’s Mental Skills Questionnaire (Bull, Albinson & Shambrook, 1996). The CSAI-2 is a sport specific self report inventory found to be a reliable and valid measure of cognitive and somatic anxiety, and self-confidence. Only the anxiety subscales are reported in the present study. The CSAI-2 assesses participants’ feelings before competing along a four-point Likert scale with response to items ranging from 1 (not at all) to 4 (very much so). Sub-scale scoring is additive yielding totals ranging from 9 to 36 for each subscale. It requires approximately 5-10 minutes to complete. The reliability of the three subscales was high ranging between 0.79 and 0.90. High Cronbach alphas of between 0.79 to 0.83 for cognitive anxiety, 0.82 to 0.83 for somatic anxiety and .87 to .90 for self confidence were established during assessment construction (Martens et al., 1990). The ACSI-28 contains 28 questions that are answered on a four-point Likert scale which ranges from 0 (“Almost never”) to 3 (“Almost always”). The questionnaire consists of seven subscales which is described by Bourgeois, Loss, Meyers, and LeUnes, (2003) as: coping with adversity, coachability, concentration, confidence and motivation, goal setting and mental preparation, peaking under pressure, and freedom from worry. Each of the seven construct scores can range from 0 to 12 that are summated to yield an overall personal coping resource score that can range from 0 to 84. Every statement in the questionnaire describes experiences of other athletes, which prompts the participant to indicate the frequency of similar experiences. The test-retest validity of the ACSI-28 questionnaire was reported by Smith et al. (1995). They reported a t-retest reliability for the general coping skills score as r = 0.87 over a one week period for a sample of 97 college athletes. Internal consistency reliability of the ACSI-28 general coping skills score was reported as r = 0.86. The Bull’s Mental Skills Questionnaire measures imagery ability, mental preparation and goal setting, self-confidence, anxiety and worry management, concentration ability, relaxation ability and motivation. The questionnaire consists of 28 items that assess respondents along a six-point Likert scale ranging from strongly agree to strongly disagree. Bull et al. (1996) standardised the questionnaire on 219 athletes to establish generally high Cronbach alpha levels ranging between 0.59 – 0.80 for the six sub-scales. The six sub-scales have also been translated into Dutch that have yielded generally similar
The relationship between psychological factors and number of injuries 313 Cronbach alpha levels (0.59 - 0.80) (Snauwaert, 2001). South African norms for the Bull’s were recently established by Edwards and Steyn (2011) on 419 male and female university students that demonstrated test-retest reliability levels concurring with three other South African studies (Danariah, 2007; Edwards & Edwards, 2007; Edwards & Steyn, 2008). The results are expressed as percentage values, with higher values indicating better skill levels. Results
The data were captured on a computer and analysed by means of the SPSS package (Statistical Product and Service Solutions). Both Pearson and Spearman Correlation analysis were done in order to confirm the results obtained. A detailed description of the prevalence, severity and mechanisms of the injuries in this study population has been published (Jacobs & Van den Berg, 2012). Table 1: Correlations between the total number of injuries and the Competitive State Anxiety Inventory-2 (CSAI-2) Variable
Mean
Std. Deviation
Minimum
Maximum
p-value
Cognitive Anxiety Somatic Anxiety Self-confidence
21.57 12.21 29.92
4.74 4.09 4.25
10.00 7.00 16.00
36.00 24.00 36.00
0.052* 0.356 0.183
Pearson Correlation (r-value) 0.168 0.080 -0.115
*p < 0.10 Table 2: Correlations between the total number of injuries and the Athletic Coping Skills Inventory-28 (acsi-28)
Maximum
pvalue
Pearson Correlation (r-value)
3.00
12.00
0.600
-0.044
1.91 2.30
2.00 2.00
12.00 12.00
0.470 0.662
0.600 0.037
9.12
2.38
2.00
12.00
0.416
-0.068
8.02
2.78
1.00
12.00
0.622
0.042
7.38
2.66
1.00
12.00
0.944
-0.006
5.68
2.66
0.00
12.00
0.426
0.068
Variable Coping with Adversity Coachability Concentration Confidence & Motivation Goal setting & Mental Preparation Peaking under pressure Freedom from worry
Mean
Std. Deviation
Minimum
7.74
2.29
6.89 7.61
314 Jooste, Jacobs and van den Berg Table 3: Correlations between the total number of injuries and the Bull's Mental Skills Questionnaire Variable
Mean
Std. Deviation
Minimum
Maximum
p-value
Imagery ability Mental Preparation Self-confidence Bulls Anxiety and worry management Concentration Ability
18.53
4.36
7.00
24.00
0.785
Pearson Correlation (r-value) 0.023
19.99
4.28
8.00
24.00
0.664
-0.037
19.01
4.90
6.00
24.00
0.461
-0.063
15.83
5.13
4.00
24.00
0.604
0.045
18.20
4.99
4.00
24.00
0.922
-0.008
Relaxation Ability
19.49
4.20
8.00
24.00
0.032*
-0.178
Motivation
20.86
3.57
8.00
24.00
0.354
0.078
*p < 0.05.
The results in Table 1 indicate that there was one statistically significant correlation between the CSAI-2 sub-scales and the total number of injuries sustained by players. There was a weak positive correlation (r= 0.168; p=0.052) between cognitive anxiety and the total number of injuries sustained. The higher the cognitive anxiety scores, the more injuries were sustained by players. This relationship is, however, not very distinct as the correlation coefficient is very low. This correlation was significant at the 0.10 level of significance. The results of the analyses in Table 2 indicate that the sub-scales of the ACSI-28 had no statistically significant correlations with the total number of injuries sustained by players. Only one statistically significant correlation was found between the sub-scales of the Bull’s Mental skills Questionnaire and the total number of injuries sustained by players (Table 3). There was a weak negative correlation (r=-0.178; p=0.032) between relaxation ability and the total number of injuries. Thus, the higher the relaxation ability scores of the players the fewer injuries they sustained. The correlation was significant at the 0.05 level of significance. Discussion This study attempted to identify psychological factors that are associated with injury occurrences in youth African soccer players. It is evident from the results that the higher the soccer players’ cognitive anxiety scores the more injuries they have recorded. Psychological explanations denote that negative appraisal of stress heightens an athlete’s vulnerability to sport injuries due to a disturbance in their movement coordination and interference in their attentional focus (Devantier, 2012). Balague (2005) contends that the movement pattern, the timing, the reaction time, and decision-making style of anxious athletes are
The relationship between psychological factors and number of injuries 315 different to their habitual, low anxiety movement patterns. This notion is supported by the Processing Efficiency Theory (Eysenck & Calvo, 1992) which proposes that athletes react to cognitive anxiety by means of worrying. Worrying reduces an athlete’s cognitive resources which impede their ability to focus on task relevant cues. Worrying also signals the criticality of the event causing the athlete to invest too much thought and effort into the skill that inadvertently affects their attentional focus. According to Williams (1996) this disruption in attention leads to a narrowing of peripheral vision that impedes an athlete’s ability to pick up or respond in time to dangerous cues in their periphery. It can, therefore, be argued that the soccer participants’ excessive amount of cognitive anxiety depleted their working memory capacity and narrowed their periphery which was needed to avoid dangerous cues in their immediate environment in the quest of performing task related skills. Interestingly, no relationship was found between increased somatic anxiety and the number of injuries sustained or subsequent injury occurrence amongst the participants. This is in contrast to findings of an investigation on high school soccer players which highlighted somatic anxiety as one of the primary predictors of injury occurrence (Johnson & Ivarsson, 2011). Similar results were also recorded for middle – low league senior soccer players (Ivarsson & Johnson, 2010). The present study’s results, however, corroborates the findings of Devantier (2012), who also could not establish a direct relationship between somatic anxiety and subsequent injury occurrence or time loss due to injury in professional male soccer players. A possible explanation why the results of the present study do not concur with the findings of the previous investigations on young or middle – low league soccer players may be the level of participation. It is likely that high level soccer players’ cognitively appraise somatic anxiety symptoms more positively compared to young and lower ranked players. Even though the participants in the present study are still aged between 14-18 years of age, they may have learned to interpret somatic anxiety symptoms as facilitative to high level soccer competition. This occurrence is partially substantiated by similar findings in the interpretation of high somatic anxiety in elite compared to nonelite cricket players (Jones & Swain, 1995). An alternative rationalisation is suggested by Lysens, Vanden Auweele, and Ostyn (1986) which claim that a prior history of injury exacerbates a participant’s stress response which heightens the risk for re-injury. Consequently, it can be assumed that the participants in the present study could have more cognitive anxiety due to a history of previous injuries. In other words the participants’ subsequent injuries resulted from their heightened cognitive anxiety that was initially elicited by a previous or current injury. It is, therefore, conclusive that high cognitive anxiety and previous injuries are more strongly related to subsequent injuries in skilled soccer players than somatic anxiety,
316 Jooste, Jacobs and van den Berg thereby causing the conjunctive role that somatic anxiety plays in injury occurrence to be less significant. No relationship between any of the coping skills and injuries sustained were recorded. This finding contradicts previous investigations (Williams, Tonymon, & Wadsworth, 1986; Smith, Smoll & Ptacek, 1990; Hanson, McCullagh & Tonymon, 1992). Smith et al. (1990), for example, revealed that ineffective coping skills in sport are directly related to the occurrence of injury. The frequently referred to stress-injury model of Anderson and Williams (1988) hypothesises that an athlete’s stress history directly contributes to the stress response, whereas, personality factors (e.g. hardiness, locus of control, achievement motivation) and coping resources (e.g. social support system, general coping behaviours, and mental skills) can act either directly or as a moderating influence on the effects of the history of stressors. Personality factors and other coping resources such as social support systems and medication were not measured in this study. It might, therefore, become apparent that the soccer players’ recorded coping skills’ acted as a much weaker moderator to injury compared to their personality and history of stressors (recent/previous injury) which, resulted in an imperceptible association with soccer injuries. Assuming that English is not the home language of this particular group of African players might also explain why results deviate from previous studies. Another rational clarification could be that the soccer participants could have not yet developed mature coping skills that are accurately reflected as they are much younger than athletes in most referred investigations. This tendency could establish a trend among younger athletes as noted by Johnson and Ivarsson (2011). The findings of the study reveal that mental skills do not play a role in the amount of injuries sustained by the participants. However, a negative correlation between relaxation ability and the total number of injuries sustained was revealed, suggesting that the higher the participants’ relaxation ability the fewer injuries they have sustained. Williams (1996) complements the effect relaxation has on reducing the risk of injury by arguing that a relaxed body could have a calming effect on the mind to the same extent that anxious thoughts could have in activating the sympathetic nervous system. This notion is accentuated by Davis (1991) who used a prevention treatment programme containing progressive relaxation to reduce injuries in collegiate swimmers and football players. Davis (1991) recorded a remarkable 52% reduction in swimming injuries and a 33% reduction in football injuries. Cupal and Brewer (2001) also demonstrated that relaxation skills not only reduce injuries in sport but also contribute in minimizing re-injury anxiety and facilitate the rehabilitation of anterior cruciate ligament knee injuries. Relaxation is thus found to be an important mental skill used by African soccer players in reducing the occurrence of injuries.
The relationship between psychological factors and number of injuries 317 Limitations and implications for further research A limitation of the current study is the fact that psychological factors (coping skills, mental skills and anxiety) were measured in the midst of an international tournament. For many, this tournament was their first which could have resulted in some players reporting their momentarily recollections and not their general psychological perceptions. Without questioning, there still remains a need to further evaluate the conjunctive role psychological factors play in association with personality factors and social support on injury occurrence in youth soccer players. The players’ individual perspective and interpretation of their complete approach of stress-coping mechanisms along with contributing stressful life events need to be considered. This will allow for a better understanding on the psychological antecedents of injury and the construction of effective injury prevention plans. Conclusion Regardless of the recognised role psychological factors play in high level sport competition, its influence on the risk of injury have been underestimated in youth sports participants. The results of this study complement existing literature by addressing the role psychological factors could have on injury occurrences in youth national soccer players. From a practical point of view it is recommended that youth soccer coaches and players consider the careful implementation of relaxation skills in an attempt to regulate cognitive anxiety in soccer injury prevention programmes. It is, however, conclusive that psychological factors play a contributing role in understanding injuries amongst youth soccer players. References American Academy of Pediatrics (AAP) (2000). Injuries in youth soccer: A subject review. Pediatrics, 105(3), 659-661. Andersen, M.B. & Williams, J.M. (1988). A model of stress and athletic injury: Prediction and prevention. Journal of Sport and Exercise Psychology, 10, 294-306. Azubuike, S.O. & Okojie, O.H. (2009). An epidemiological study of football (soccer) injuries in Benin City, Nigeria. British Journal of Sports Medicine, 43(5), 382-386. Balague, G. (2005). Anxiety: From pumped to panicked. In S. Murphy (Ed.), The Sport Psych Handbook (pp. 73-92). Champaign, IL: Human Kinetics. Bourgeois, A.E., Loss, R., Meyers, M.C. & LeUnes, A. (2003). The Athletic Coping Skills Inventory: Relationship with impression management and self-deceptive aspects of socially desirable responding. Psychology of Sport & Exercise, 4, 71-79. Bull, S., Albinson, J. & Shambrook, C. (1996). The Mental Game Plan. Getting Psyched for Sport. Eastbourne: Sports Dynamics.
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