ABSTRACT
This case-control study aimed to analysis of the relationship between individual behaviours and sports risk factors and injuries among skiers and snowboarders. During the 2021–2022 winter season, 1132 injured and 1069 non-injured skiers and snowboarders were surveyed regarding demographic, self-reported individual behavioural and sporting characteristics. Multivariate regression analysis revealed previous snow-sports injury (OR: 26.39, 95% CI: 13.32–52.31, P < 0.001), nervousness (OR: 3.78, 95% CI: 2.91–4.90, P < 0.001), calm (OR: 1.90, 95% CI: 1.46–2.48, P < 0.001) and fearful (OR: 20.60, 95% CI: 11.45–37.04, P < 0.001) emotional states, and higher risk-taking behaviours (OR: 3.72, 95% CI: 2.87–4.83, P < 0.001) were important risk factors associated with injuries to all skiers and snowboarders. Compared to snowboarders, the risk of injury to skiers was more likely to increase as the length of their skiing experience increases. Emotional and cognitive levels appear to be important conditions that influence injuries to skiers and snowboarders, a proper understanding of the potential interactions between cognition and behaviour appears to be important for public ski safety management.
Introduction
Recreational alpine skiing and snowboarding are winter sports loved by hundreds of millions of sports enthusiasts (Hume et al., Citation2015), especially in China, which has successfully bid to host the Beijing Winter Olympics. However, with the rapid increase in the number of skiers and snowboarders, the number of sports injuries caused by ski-accidents is also increasing. A local study investigated injury rates at the 2022 Beijing Olympic Games competition venue for the 2017/2019 and 2018/2019 snow seasons of 5.9 injuries per 1,000 skier days and 4.9 injuries per 1,000 skier days, respectively (Yang et al., Citation2020). Despite improvements in field and snowmaking technology, the injury rate in China is currently calculated to be higher than in European and American countries during the same period (Gomez & Rao, Citation2016). Therefore, it is important to recognize the risk of winter snow sports injuries and safety measures should be developed for at-risk populations.
A previous systematic review reviewed a large number of studies on recreational snow sports injury recommendations and found that more than 70% of the studies focused on equipment, education and knowledge, awareness and behaviour, experience and skill level (Hébert-Losier & Holmberg, Citation2013). In addition, awareness and recognition of potentially dangerous situations and conditions, individual skill and ability levels, participation in snow sports related courses, and third party initiatives such as ski resorts, ski patrollers, and sport retailers were all identified as important players in injury prevention (Hébert-Losier & Holmberg, Citation2013).
The skill level and experience of skiers and snowboarders is important for injury prevention, which is in part related to the individual’s level of adaptation to the specific sport (Langran, Citation2002; Mckenna & Hammond, Citation2007). From a sports biomechanics perspective, the use of protective equipment and gear plays a role in preventing snow-sports injuries associated with high speeds and impacts (Hébert-Losier & Holmberg, Citation2013). Theoretically, the simultaneous increase in understanding of sports biomechanics, exercise physiology, and sports psychology should translate into the use of targeted and comprehensive strategies to prevent sports injuries (Hébert-Losier & Holmberg, Citation2013; Kiani et al., Citation2010). potentially significantly reducing the medical costs and morbidity associated with participation in snow-sports (Hébert-Losier & Holmberg, Citation2013).
Due to the lack of available research evidence, a comprehensive analysis of individual behavioural, psychological, risk awareness, equipment protection and experience levels seems necessary before further use of an integrated approach to develop prevention strategies to provide new recommendations for recreational skiers and snowboarders to prevent injuries in alpine skiing. The authors therefore conducted a case-control study to investigate the impact of a number of putative risk factors, including individual behavioural and sporting characteristics, on overall injury risk in skiing and snowboarding, to provide evidence for the effectiveness of injury prevention strategies in recreational snow-sports.
Methods
This retrospective case-control study was conducted during the 2021–2022 winter season in a large ski and snowboard resort in Beijing, China. This study was approved by the ethics committee of Beijing Sport University and was conducted in accordance with the guidelines of the Declaration of Helsinki. Cases and controls were informed of the study objectives and consent for participating, their personal information was processed anonymously.
Cases were all adult (≥18 years old) skiers or snowboarders who were injured at the ski resort. Injuries were recorded when a skier or snowboarder was treated or consulted by ski patrol or physician at a ski clinic (located directly on the ski resort) after an accident on a ski area. Inclusion criteria were injuries related to skiing or snowboarding, and for patients with multiple documented injuries were considered as one case. The control group was all adult (≥18 years) skiers or snowboarders who were not injured at the ski resort. To minimize the potential impact of environmental factors (e.g. weather and slope conditions) on injury risk, a control group was randomly selected on the same days at the same ski area (Posch et al., Citation2019; Ruedl et al., Citation2019).
During the 2011/2012 winter season (between 1 November 2021 and 31 March 2022), injured skiers and snowboarders were interviewed via questionnaires about demographics and individual behavioural and sporting characteristics. The control group was randomly recruited by staff uninformed about the purpose of the study, and questionnaire interviews were administered to uninjured skiers and snowboarders as they left the ski slopes. Cases were interviewed on the day of or the day after the injury. Questionnaires about demographics and individual behavioural and sporting characteristics were also used in the control group. During the study period, a total of 1132 patients (81% response rate) met the inclusion criteria and completed the questionnaire interview, of the non-injured skiers and snowboarders who were interviewed and completed the questionnaire, a total of 1069 met our screening criteria and were included in the control group, with no significant differences in demographic characteristics between the control and case groups ().
Table 1. Baseline characteristics of skiers and snowboarders in injured and uninjured groups. (n = 2201).
A total of 21 variables including demographics, individual behavioural and sporting characteristics were interviewed. Demographic variables are as follows: age, sex, snow-sports type (skiing or snowboarding), height, weight, and BMI. The variables associated with injury-related individual behavioural risk factors were self-reported state of mood while skiing or snowboarding (classified in excited, nervous, scared and calm), warm up before skiing or snowboarding (classified in no warm-up, ≤ 10 minutes, > 10 and ≤20 minutes, > 20 and ≤30 minutes and >30 minutes), self-reported degree of risk-taking behaviour (more risk-taking versus more cautious) (Russell et al., Citation2015), attention to security education/alerts before skiing or snowboarding (yes/no). Regarding snow-sports equipment, the use of six different types of protectors (helmets, snow goggles, hip pads, elbow pads, knee pads and wrist guards) and whether ski/snowboard bindings were adjusted and maintained (i.e. bindings testing) were included in the analysis. The variables related to the sporting characteristics were previous snow-sports injury (yes/no), snow-sports experience, which representing the total time spent in skiing or snowboarding (frist time, more or less than one snow season), professional snow-sports training experience (yes/no). In addition, the self-evaluation skill level was classified into three categories (refer to the “Recreational Skiing and Snowboarding Skill Level Standards” issued by the State Sport General Administration of China in 2019, grades 1–3 were defined as beginner, grades 4–6 were defined as intermediate, grades 7–9 were defined as expert, the items concerned are presented in Appendix 1).
All data analysis were performed using SPSS version 26 (IBM, New York, NY, USA). After testing for normality distribution (Kolmogorov-Smirnov), continuous variables (age, height, weight, and BMI) in cases and controls were compared by Mann-Whitney U Tests and were presented as medians with inter-quartile ranges (IQRs). Differences in frequencies of categorical variables (all variables except continuous variables) were evaluated by chi-square tests and expressed as numbers (n) and percentages (%). We used logistic regression analysis to assess the relationship between individual behavioural and sporting characteristics and injury. To select potential confounders, we performed a univariate analysis of the relationship between all included variables and injury. To analyse the specific risk factors affecting skiing and snowboarding injuries, we performed univariate and multivariate logistic regression analyses by subgroups of different snow-sports. Factors with P < 0.05 were used as adjustment factors for potential confounding and were included in the multiple logistic regression model. Results were presented as unadjusted (crude) and adjusted odds ratio (OR) and 95% confidence intervals (CI), a two-sided P < 0.05 was considered to be statistically significant.
Results
The population studied consisted of 49.7% male in injured group and 48.2% male in uninjured group, with a median age of 28 years for injured group and 29 years for uninjured group (). The age of all samples ranged from 18 to 58 years, and the median BMI was 20.8 in injured group and 21.1 in uninjured group (). In both groups, the proportion of skiers was slightly higher than the proportion of snowboarders.
Injured individuals self-reported that they were more likely to feel nervous and scared while skiing or snowboarding, compared to the majority of uninjured individuals who felt excited (64.9%). More than 95% of both groups warmed up before skiing or snowboarding and more than 90% complied with safety education or warnings. In addition, injured skiers and snowboarders were more willing to engage in risky behaviours (76.1%) than those who were not injured (56.6%). There were no significant differences in helmet use or binding tests between the two groups, while the uninjured used more snow goggles, hip pads, elbow pads, knee pads and wrist pads (). Among the injured group, 20% of skiers and snowboarders reported having suffered a previous snow-sports injury, while 99% of the uninjured had not experienced a snow-sports injury (). In both groups, more than 65% of skiers and snowboarders had experienced more than one season, and less than 10% were first-time participants. Almost half of the sample in both groups had experienced professional snow-sports training. More than half of skiers and snowboarders self-reported their skill level as beginner, while no more than 5% were experts.
Table 2. Distribution of individual behavioural and sporting factors of skiers and snowboarders in injured and uninjured groups. (n = 2201).
The results of crude and adjusted logistic regression analyses of the relationships between injuries and individual behavioural and sporting risk factors are shown in . In the crude model, previous injury, sport experience, professional training experience, self-assessment of skill level, state of mood, use of snow goggles, hip pads, elbow pads, knee pads and wrist guards, degree of risky behaviour and attention to security education/alerts were important risk factors. Use of helmets and binding tests were not associated with injuries to skiers and snowboarders.
Table 3. Results for univariate and multivariate logistic regressions.
Using multiple logistic regression analysis of the relationship between cases and controls, the authors found that prior injury was a high risk factor for recurrent injury in snow sports (aOR = 26.39, 95% CI = 13.32–52.31, P < 0.001). Skiers and snowboarders who have experienced one or more snow seasons had an increased risk of injury compared to first-time snow sports participants (aOR = 1.78, 95% CI = 1.10–2.90, P = 0.02; aOR = 2.62, 95% CI = 1.61–4.27, P < 0.001). Injuries to skiers and snowboarders were not related to professional skill training experience or their skill level. Compared to excitement, being nervous or calm while skiing or snowboarding might lead to an increased risk of injury (aOR = 3.78, 95% CI = 2.91–4.90, P < 0.001; aOR = 1.90, 95% CI = 1.46–2.48, P < 0.001), while fear could greatly increase the risk of injury (aOR = 20.60, 95% CI = 11.45–37.04, P < 0.001). The use of both hip and elbow pads could reduce the risk of injuries to skiers and snowboarders (aOR = 0.74, 95% CI = 0.59–0.92, P = 0.007; aOR = 0.74, 95% CI = 0.50–1.08, P = 0.029). Skiers and snowboarders who were more willing to take risks were more likely to be injured (aOR = 3.72, 95% CI = 2.87–4.83, P < 0.001), and attention to safety education or warnings before engaging in snow-sports could reduce the risk of injury (aOR = 0.55, 95% CI = 0.32–0.94, P = 0.028). Warming up, using snow goggles, knee pads and wrist guards were not associated with injuries.
The results of the subgroup analysis showed that common risk factors for injury among snowboarders and skiers were previous snow-sports injury, the mood of calm and nervous and scared and risk-taking behaviours, which was consistent with the overall analysis (). Skiers with more experience were more likely to be injured than snowboarders, and snowboarder injuries appeared to be more influenced by whether or not they were concerned about safety education/alerts (aOR = 0.38, 95% CI = 0.17–0.80, p = 0.014). The use of elbow pads could reduced the risk of injury among snowboarders (aOR = 0.66, 95% CI = 0.44–0.98, P = 0.042), while the use of hip pads could reduced the risk of injury among skiers (aOR = 0.63, 95% CI = 0.46–0.85, P = 0.003).
Discussion
The primary objective of this study was to assess potential injury risk factors for recreational alpine skiers and snowboarders through analysis of individual behavioural and sporting characteristics. Multiple regression analysis revealed previous snow-sports injuries, more risky behaviours, nervousness, fear, or lack of excitement as independent risk factors for participants in snow-sports, and skiers were more likely to be at increased risk of injury as the length of their skiing experience increases.
Skiers or snowboarders with a history of musculoskeletal injuries have reduced ligament strength and proprioception at the site of injury, so they are more likely to have repeat injuries, known as habitual injuries (Zemper, Citation2003). In a retrospective cohort study, snowboarders with past sports injuries had a 1.35-fold higher risk of re-injury than snowboarders with no history of injury (Machold et al., Citation2000). In competitive and adventure sports, previous injury experiences greatly increase an athlete’s risk of re-injury in the same area. In competitive and adventure sports, the experience of previous injuries greatly increased the risk of re-injury in the same area of the athlete (Schulz et al., Citation2004; Tyler et al., Citation2006). Structural and functional imbalances in the body caused by old injuries may be amplified during snowboarding and skiing, resulting in excessive tension and tension on certain muscles, ligaments, joint capsules and other tissues, resulting in a greatly increased risk of injury (Deady & Salonen, Citation2010).
Our study found that the risk of injury increases with the amount of time a skier experiences. Snow-sports belong to a long time high-intensity aerobic exercise, so in the process of exercise, the formation of a long time of subtle injuries accumulate over time, will eventually affect physical function and athletic ability, indirectly affecting the accuracy of the action, and movement control level decline and easily induced sports injuries, thus forming a vicious circle (Kellmann, Citation2010). Compared to snowboarders who rely more on the back and forth movement of the centre of gravity to make directional changes, skiers use a lot of knee changes to make directional changes, which increases the wear and tear on lower extremity joints such as the knee joint as skiing time increases, as a result, skiers are more likely to suffer from injuries induced by chronic lower extremity strain (Deady & Salonen, Citation2010).
Our study appears to be consistent with previous studies who concluded that skiing injuries are more likely to occur with high-risk behaviours (Ruedl et al., Citation2019). In addition, some studies have shown that high-risk behaviours that fall into the same category of psychological factors as emotional state greatly increase the risk of injury (Willick et al., Citation2017). However, another study used Zuckerman’s Sensation Seeking Scale (SSS) to evaluate the degree of risk-taking behaviour, and injured skiers had lower thrill and adventure seeking (TAS) scores than uninjured skiers (Bouter et al., Citation1988). The pathogenesis of the association between high-risk behaviour and injury is unclear due to the differences in evidence from the above studies, and we suspect that it may be related to the choice of slope and skating speed. Further research is needed to determine whether there is an interaction between different levels of risk-taking demands and emotional states in the corresponding situations.
Although the role of psychological care and mental preparation in sport and competition has long been recognized, the importance of psychological factors on injury risk has been underestimated (Junge, Citation2000). Specifically, psychosocial stressors, coping resources, and situation-dependent emotional states appear to influence athletes’ risk of sports injury (Junge, Citation2000). The relationship between emotional arousal and physical function resembles an inverted U-shaped curve, in that physical arousal increases and then decreases with increasing emotion, and negative attitudes or decreases in emotional level can significantly affect and delay movement completion and even lead to injury (Li-Jun, Citation2014; Wang & Jia-Wei, Citation2015). In addition, nervous and fearful emotions can lead to neuromuscular tension, movement distortion, and greatly increase the risk of injury (Li-Jun, Citation2014). Consistent with the above studies, we found that both low emotional arousal (calm) and high emotional arousal (nervousness, fear) increased the probability of injury compared to an aroused state. Notably, unlike the relatively stable and controlled environment in the above studies, alpine skiers and snowboarders move in a more complex and dynamic environment and may be more sensitive to the effects of situation-dependent emotional states (Russell et al., Citation2015).
We found that hip pads significantly reduced the risk of injury for skiers, while elbow pads significantly reduced the risk of injury for snowboarders. One study found that snowboarders have an elbow injury rate of 46.9%, and elbow injuries are mainly manifested as posterior elbow dislocation and fractures (Takagi et al., Citation1999). Because snowboarders’ feet are firmly anchored to their boards, they cannot extend their stance, so the full impact of a fall is usually absorbed by the upper extremities, resulting in shoulder, elbow and wrist injuries (Matsumoto et al., Citation2002). The mechanism of injury may be elbow hyperextension during a fall, resulting in longitudinal thrust of the proximal radius, ulna and distal humerus and causing extension fracture of the elbow. Therefore, the use of elbow pads can prevent elbow hyperextension during a fall, cushion the impact of the fall and provide some protection to the entire upper limb joints (Takagi et al., Citation1999). The regular position for a skier to fall is sitting down backwards or to the right rear, using the hips to land, with the hands at the sides, in a certain group position (Hagel, Citation2005). Wearing a hip protector could cushion the impact of a fall and reduce the risk of injury, and skiers may prefer to land on their hips when they fall, thus greatly reducing the risk of finger injuries and knee sprains (Deady & Salonen, Citation2010).
Consistent with our findings, a previous study suggested that lack of ski safety education was a risk factor for injury (Macnab et al., Citation1998). The behavioural motivation hypothesis theory can be used to explain this phenomenon, which suggests that the perception of high risk of injury encourages people to act (increase protective behaviours or change pre-existing risky behaviours) to reduce their risk (Steven & Rogers, Citation1986). However, no research evidence has been found to date on the differential effect of safety education on reducing injury risk for snowboarders and skiers respectively. It is suggested that a prospective cohort study could be conducted in the future to differentiate between snowboarders and skiers regarding the effectiveness of safety education interventions.
Our study has several limitations. Firstly, because the inclusion of injured patients was limited to the same ski clinic, possible selection bias could not be excluded, and recall bias was inevitable as injured patients completed the questionnaire at different times within one to two days of injury. Secondly, we considered the exclusion of those under 18 years of age due to the large deviation of minors’ understanding and expression from the true situation, so the assessment of injury risk in this population was inadequate. Thirdly, over 95% of both injured and uninjured skiers and snowboarders used a helmet and warmed up before exercise, which may limit the assessment of the potential association between helmet use and warm-up levels and injury. Fourth, due to technical limitations, we only considered the inclusion of individual factors, and additional environmental variables need to be included to further explore the influence of external risk factors on injury.
Conclusions
In summary, this study provides controversial findings that high versus low emotional arousal during exercise largely influences the risk of injury in skiers and snowboarders, and in addition self-reported risky behaviour was shown to be a correlate of injury, with participants with previous snow-sports injuries and those with longer skiing experiences at higher risk of injury. These results suggest that injury in recreational skiing and snowboarding is a multifactorial issue in which individual behavioural risk under psychological and cognitive associations plays an important role in injury. The study also raises important questions for ski management about how to improve specific training and outreach to improve hazard awareness and risk-averse personal management among skiers and snowboarders to better reduce the occurrence of injuries.
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References
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