Characterising the movement patterns of women's beach volleyball using global positioning systems

Abstract

The aim of this thesis was to describe the movement patterns of women’s beach volleyball using global positioning systems (GPS) technology. This aim was completed in two parts: Part A involved the investigation of the level of agreement between an emerging GPS system (VX Sport VX235 Log, Visuallex Sport International Ltd, Lower Hutt, New Zealand) and a well- established GPS system (Catapult MinimaxX S4, Catapult Innovations, Melbourne Australia). We recruited five semi-professional beach volleyball athletes who wore the two GPS units (sampling at 10 Hz) simultaneously during a training session which involved beach volleyball drills and simulated match-play. A paired sample t-test with statistical significant set to p<0.05 was applied to examine whether differences existed in the measurements of total distance (m), average speed (m∙min-1), max velocity (m∙s-1) and the distance (m) covered in five distinct velocity zones during a beach volleyball training session between the two different brands of GPS units. Significantly greater average speed (38.3 ± 5.66 m∙min-1, p = 0.009), and the distance covered between speeds of 4-8 km∙h-1 (248 ± 207 m, p = 0.008) and 16-20.5 km∙h-1 (8.78 ± 7.40 m, p = 0.006) were reported by the Catapult S4 units compared to the VX235 GPS units (35.9 ± 3.45 m∙min-1, 206 ± 168 m and 1.64 ± 2.62 m respectively), in conjunction with the VX235 units reporting a greater max velocity (4.37 ± 0.68 m∙s-1, p = 0.013) compared to the Catapult S4 units (4.07 ± 0.60 m∙s-1). These results demonstrate that differences exists between the emerging VX235 GPS system and the well-established Catapult S4 GPS system for measuring the movement patterns during beach volleyball, supporting the notion that further validation of GPS units against other practically applied and validated athlete movement trackers is required to further understand the ability of GPS systems to measure the movement patterns of beach volleyball. Part B of this thesis involved the application of the 10 Hz VX235 GPS unit to quantify the movement patterns of women’s beach volleyball match-play. Specifically the VX235 GPS unit was worn by twenty female beach volleyball athletes during competition matches from the U23 Australian beach volleyball championship (n=10) and the Queensland Open tournament (n=10). The results form Part B of this thesis describe women’s beach volleyball athletes as covering a total distance of 555 ± 129 m and an average speed of 36.2 ± 3.2 m∙min-1, in addition to the majority of the distance covered occurred at speeds between 0-3.9 km∙h-1 (274 ± 63.6 m) and 3.9-7.8 km∙h-1 (203 ± 57.3) during match-play. The magnitude of these physical measures resulted in an average heart rate of 159 ± 12.0 bpm and 71.3 ± 30.4% of time with a heart rate ≤168 bpm. An independent sample t-test with statistical significant set to p 5 points). A paired sample t-test with statistical significant set to p 5). In addition all physiological measures of heart rate displayed no significant difference between sets that ended with a small score margin and sets that ended with a large score margin with the exception of the percentage of time spent with a heart rate between 80-85% of each athletes age-predicted max heart rate which was significantly greater for sets that ended with a small score margin (25.8 ± 16.3%, p = 0.013) compared to sets that ended with a large score margin (16.0 ± 17.1%). The results from Part B of this thesis were the first to identify the movement patterns of women’s beach volleyball and provide insight into the presence of fatigue and the effect of score margin differential. The results provide information to assist in preparing women’s beach volleyball athletes for the demands they are likely to undertake during competitive match-play.