Heat stress incidence and matchplay characteristics in Women's Grand Slam Tennis

Abstract

ObjectivesTo explore the relationship of wet bulb globe temperature (WBGT) on heat-related incidents and alterations in matchplay and behavioural characteristics in women’s tennis at the Australian Open. DesignFrom 360 main draw Australian Open women's matches (2014-2016), data describing on-court calls for trainers, doctors, cooling devices and water, post match medical consults and matchplay characteristics were collated. MethodsData were referenced against estimated WBGT and categorised into standard zones (zone 5: >32.3°C, zone 4: 30.1–32.2°C, zone 3: 27.9–30°C, zone 2: 22.3–27.9°C, zone 1: <22.2°C). Generalized linear models assessed the association of WBGT zone on heat-related medical incidences, court call-outs and match characteristics. ResultsWith an increased estimated WBGT zone, there was an increase in total trainer calls (+19.5%/zone; p=0.019), total doctor calls (+54.1%; p<0.001), total calls for heat related incidents (+55.9%; p<0.001), and cooling devices (+31.4%; p<0.001) calculated from the regression slope. When match characteristics were adjusted for match quality, significant decreases (p<0.001) in the number of winners and net approaches and increase in double faults were associated with increased estimated WBGT zone. ConclusionsAn association between higher estimated WBGT and medical callouts (heat and non-heat related) was evident, with an increased call rate >32°C WBGT, despite no heat-related retirements. As estimated WBGT increased, the number of winners and net approaches were reduced, while double faults increased, particularly >30°C WBGT. Accordingly, the manner in which female players manage and play in the heat during women’s Grand Slam tennis appears to change at ≈30°C WBGT.