Physical Activity and Climate Change: Clear and Present Danger?

Abstract

Objective: By the year 2100, the Earth's mean temperature could increase 1.8°C to 4.0°C, in part due to the release of greenhouse gases (GHGs). This increase may negatively influence personal health, directly through GHG emissions and increased temperature, and indirectly through climate change's impact on the environment. The potential effect of climate change on physical activity (PA), and in turn, obesity, is less clearly understood. Methods: We carried out an integrative review of English-language peer-reviewed published papers to improve understanding of how climate change may influence PA and obesity. Results: From an initial retrieval of 4587 papers, we condensed the search to 19 using a PRISMA approach. Eight papers reported individual physiological responses to excessive heat during PA, primarily among elderly persons, with 11 others providing broad implications for PA trends over time in conjunction with climate change. Conclusion: Overall, excessive heat exposure during PA has greater impact on the elderly whose bodies are less able to thermoregulate core temperature, placing increased strain on cardiovascular and respiratory systems. Because elderly individuals report more cardiovascular and respiratory illnesses than the overall population, climate change may exacerbate these conditions during PA. Rising temperature may decrease PA prevalence, especially during summer, thereby increasing sedentariness. Rising temperature could decrease PA frequency and intensity, and concomitantly, place already vulnerable populations in life-threatening situations.