Author(s): OLEARY, K., CALDWELL ODGERS, J., Institution: MONASH UNIVERSITY, Country: AUSTRALIA, Abstract-ID: 1221

INTRODUCTION:
Maintaining a high level of aerobic fitness through regular physical activity (PA) is strongly associated with greater physical and mental health in older adults, and is a key strategy for preventing and managing chronic diseases (1). Current guidelines recommend that Australians aged 65+ complete at least 30 minutes of moderate intensity exercise on most days (2). However, aging is accompanied by impaired thermoregulation, which is increasingly concerning given rising global temperatures and the increased frequency of extreme heat events (1, 3). These facts may increase the risk of overheating during exercise, yet there is limited evidence on whether older adults modify their PA in hot conditions, or if these adjustments are effective at mitigating hyperthermia risk. Therefore, the aim of this study was to compare the current PA habits of older adults in both thermoneutral and hot conditions, to identify potential risk points and strategies to alleviate the risk of hyperthermia. It was hypothesised that increasing age and temperature would decrease PA time, and that the type of PA engaged in would be of lower intensity.
METHODS:
389 Australian adults aged 45+ were recruited to complete a survey regarding their PA habits in thermoneutral and hot environments. The survey incorporated the international physical activity questionnaire (IPAQ), demographics, questions regarding types of PA, and adverse effects from exercising in the heat (4). Data were analysed using a linear mixed model in SPSS.
RESULTS:
Days with walking, and time spent walking and engaging in moderate PA were significantly reduced in hot compared to thermoneutral conditions (4.28±0.15 versus 4.71±0.15 days, P=0.001; 71.33±6.14 versus 85.94±5.75 mins, P=0.016; 67.31±6.01 versus 85.67±5.58 mins, P=0.001). Older adults walked on significantly fewer days than younger adults (P=0.002). Engagement in swimming was significantly higher in hot compared to thermoneutral conditions (P=0.001). Age was a predictor of how many types of PA an individual participated in, with older individuals engaging in significantly less activities compared to younger individuals (P=0.004).
CONCLUSION:
Older adults engage in less PA when temperatures are high, and are less likely to achieve PA targets (2). Water based activities such as swimming were more common when temperatures were high and may be more suitable alternatives during hot conditions. As this study was conducted across Australia, there may be variation in individual experiences with heat dependent on location within Australia. For optimal health and wellbeing of older adults, guidelines should include appropriate adaptations to exercise when temperatures are high to reduce the risk of overheating whilst reaching PA goals.
REFERENCES:
[1] Stapleton 1985/ [2] Australian Government 2014/ [3] Lamarche 2017/ [4] Lee 2011