Heat illness surveillance in schoolboys participating in physical education class in tropical climate: an analytical prospective descriptive study

Abstract

ObjectivesThis study aimed to determine thermoregulatory and cardiovascular responses as well as the occurrence of heat illness in children exercising outdoors in physical education class under hot and humid climate. Little information regarding this issue under real-life situation is available, especially in the Southeast Asia.DesignAnalytical, prospective descriptive study.SettingA primary school in Bangkok, Thailand.ParticipantsA total of 457 schoolboys (aged 5.5–12 years) were observed while exercising outdoors during their physical education classes throughout the academic year of 2009, including semester 1 (between July and September 2009) and semester 2 (between November 2009 and February 2010).Primary and secondary outcome measuresPrimary outcome measure was tympanic temperature. Secondary outcome measures included blood pressure, heart rate, hydration status and the occurrence of heat-related illness.ResultsOutdoor physical activity consisted of skill practice (duration 24.11±11.04 min, intensity <3 metabolic equivalent of tasks) and playing sports (duration 11.48±5.53 min, intensity 2.6–8.8 metabolic equivalent of tasks). After exercise, tympanic temperature increased by 0.66±0.41°C. There were 20 (4.4%) students whose ear temperature exceeded 38°C, 18 of whom did not consume water. The RR of increasing body temperature up to 38°C in overweight students was 2.1-fold higher than normal-weight students. The per cent change in mean arterial pressure and heart rate increased by 20.16±15.34% and 23.94±19.78%, respectively. Sweat and dehydration rates were 391.16±186.75 ml/h and 0.63±0.26%, respectively. No evidence of heat illness was found. Wet bulb globe temperatures of semesters 1 and 2 were 29.95±1.87°C and 28.32±2.39°C, respectively.ConclusionsThere is an increased risk for heat illness during outdoor activities in physical education class in primary school children, especially those who are overweight and have poor hydration status.

Sports Dietitians Australia Position Statement: Sports Nutrition for the Adolescent Athlete

“…Unfortunately, there is no evidence to determine the extent to which (if at all) fluid intake may modulate the risk of heat illness in adolescent athletes. This is because fluid monitoring studies on children and adolescents at risk for heat-illness are scarce and often fail to report participants who actually experience heat-illnesses (Somboonwong et al, 2012). In contrast, field studies indicate that adolescent athletes can experience significant deficits in fluid (≤4% body weight) during training and competition in the heat (Aragon-Vargas et al, 2013;Silva et al, 2011).…”

Climate change and adolescents in South Africa: The role of youth activism and the health sector in safeguarding adolescents’ health and education

“…[11] Adolescents and adults have similar physiological thermoregulatory mechanisms, [12] but adoles cents may lag in behavioural thermoregulation, for example owing to inadequate fluid intake. [13] Compared with boys, the effects on girls may be greater, given that they have higher rates of obesity (which compromises thermoregulation), and of mental health conditions and mortality during extreme weather events. [14] Similarly, subgroups of adolescents with limited physical or monetary resources to counter the impacts of climate change, such as those living in extreme poverty or with disabilities, may also be at increased risk.…”

‘Heat-Smart’ schools during physical education (PE) activities: Developing a policy to protect students from extreme heat

“…The main concern from the impact of heat is that if PE classes are held in intense heat, students may become vulnerable to heat injury and impaired learning (Somboonwong, et al, 2012). Therefore, when preparing a quality PE program, the quantity and intensity of the physical activities needs to be taken into consideration.…”

“…NSW Government, 2016;SA Government, 2016 • Avoid surfaces that exhibit radiant heat that include concrete, black asphalt or black rubberised synthetic surfaces which can intensify hot conditions • Doecke, 1992;SMA, 2007SMA, -2011 • Hydration programs • Somboonwong, et al, 2012 • Increasing amount of drinking taps/ fountains…”