Browsing by Author "Glossop-von Hirschfeld, Christine"
Now showing 1 - 1 of 1
Results Per Page
Sort Options
- ItemOpen AccessProprioception, jumping capacity and agility in beach versus indoor volleyball players(2021) Glossop-von Hirschfeld, Christine; Smits-Engelsman, Bouwien; Ferguson, GillianBackground: Beach volleyball (BVB) is rapidly developing into a popular activity both for recreational and competitive athletes. The majority of injuries sustained playing volleyball (beach and indoor) are considered non-contact. While commonly injured areas (ankle, knee, lower back and shoulder) are similar in beach volleyball (BVB) and indoor volleyball (IVB), injury incidence in BVB players is reported as 3.9-4.9 per 1000 hours, which is significantly lower than in IVB (1.7-10.7 per 1000 hours). Several factors contribute to the level of performance as well as to injury risk in volleyball players: body composition, changes in training load, previous injury, balance, proprioception, joint kinematics and muscle strength. There has been recent growth in the literature investigating the role of proprioception in the assessment, management and prevention of musculoskeletal injuries. Proprioceptive retraining strategies are diverse and yet no conclusive evidence demonstrating the superiority of one exercise over another is available. However, consensus exists that proprioceptive training requires movement on an unstable or uneven surface. Although proprioceptive exercises are commonly integrated into sports rehabilitation, there is a lack of high-quality evidence proving that proprioception can be trained. Maximal vertical jumping, lateral cutting sprints and diving to play the ball are repetitively demanded of volleyball players. BVB players complete these actions on sand (an uneven and unstable surface), making this sport, by definition, a continuous proprioceptive training exercise. By comparing two groups (IVB and BVB players) who perform a very similar sport on different surfaces (indoor and sand), we wish to investigate whether this may have led to differences in proprioception. Furthermore, we would like to measure the possible influence of this training aspect on functional capacity (lower limb range and strength, agility and vertical jump height). Aim: To compare proprioception, functional lower limb capacity, agility and jumping capacity on two different surfaces, between non-professional BVB and IVB players. Methods: A descriptive, cross-sectional, analytical study was conducted. The study adhered to the research ethics guidelines of the Declaration of Helsinki. The study protocol was submitted and approved by the Faculty of Health Sciences Human Research Ethics Committee, University of Cape Town. Convenience sampling was used to recruit 30 non-professional volleyball players (15 BVB and 15 IVB players) in the Western Cape, who met the inclusion criteria. Each player attended a testing session where they were given an informed consent sheet. If they decided to consent to participate and sign the form, a screening questionnaire was administered to determine eligibility to participate. Due to the COVID pandemic, participants also completed a COVID-19 screening tool. If eligible to continue to take part in the study, participants completed two questionnaires (Training and Injury History questionnaire and OSTRC (Oslo Sports Trauma Research Centre) questionnaire), after which they completed seven physical tests (the wedge test, two-point discrimination test, modified balance error scoring system (mBESS) test, modified star excursion balance test (mSEBT), knee-to-wall test, single leg hamstring bridge test (SLHBT) and eccentric-concentric calf raise test). They then proceeded to perform two jumping tests (countermovement jump with arm swing (CMJA) test and single leg triple hop for distance (SLTHD) test) and an agility test agility (modified agility T-test (MAT)) both on sand and hard surfaces. Descriptive statistics were used to present the demographical data, training and injury history. A t-test was used to determine whether the two groups were comparable on anthropometric data. Differences between the two groups (BVB and IVB players) in proprioception, agility and jumping capacity were analysed using Mann-Whitney U and unpaired t-tests. Repeated measures ANOVA were used to determine any differences in agility, jumping height or hopping distance between IVB and BVB players when tested on different surface conditions (the surface being the within-group factor and player type being the between-group factor). Effect size analysis was also reported for the physical outcome measures data, to determine the strength of any trends in differences existing between the two player groups Results: IVB and BVB groups were similar regarding demographics, training history and injury prevalence. Age was the only variable found to be significantly higher in BVB players than IVB players (p = <.001). There were no significant differences in most measures of balance, strength, agility or jumping capacity between the groups. While the results of the proprioception measure (wedge test) were also not significant (p= 0.08), a medium effect size (Cohen's d = 0.66) was found, with the BVB group identifying more differences in wedge heights correctly. There was a significant difference in the anterior reach of the Y-balance test (right and left legs) between the groups (p < 0.05), with the BVB group out-performing the IVB group. The study showed no significant correlations between proprioceptive measures and functional outcomes. A repeated-measures ANOVA determined that there was a significant main effect of surface type on mean CMJA heights (Wilks' Lambda = 0.799, F (1,28) = 7.040, p = .013), mean left leg SLTHD distances (Wilks' Lambda = 0.522, F (1,28) = 25.654, p = < .001) and mean right leg SLTHD distances (Wilks' Lambda = 0.473, F (1,28) = 31.169, p = < .001). However, no surface by player group interactions emerged, indicating that the impact of the surface was not different between groups of players: All volleyball players ran faster, jumped higher and hopped further on the indoor floor than on the sand. Discussion and conclusion: The findings of this study suggest that there are no consistent differences in functional capacity between IVB and BVB players. Despite limited findings, the current study contributes to the literature, as it is one of a few studies to assess the effect of habitual sand training on functional performance measures between IVB and BVB players. It is hoped that this study could provide a basis for further investigation into training on different surfaces to improve functional outcome measures, for overall performance improvement.