Too Hot to Move? Climate Change, Extreme Heat and Physical Activity in Sub-Saharan Africa: Implications for Health Equity and Climate Adaptation

Evidence linking environmental temperature to physical activity derives largely from high-income settings, where research often measures discretionary leisure exercise. In Sub-Saharan Africa, pooled survey estimates indicate participation of 18.9% in leisure activity, compared with 70.1% in work-related activity and 86.2% in travel-related activity. This protocol-registered critical narrative review distinguishes discretionary activity from obligatory activity, including livelihood work, essential travel, water and fuel collection, domestic work and caregiving. Eight registered PubMed/MEDLINE searches were executed and translated for Europe PMC, with paired counts documented for all translations, supplemented by citation searching of 11 anchor records. Records were charted in a structured evidence matrix and quantitative claims checked against primary sources where accessible. The evidence suggests that responses to heat depend partly on whether activity can be modified. Among self-paced Burkinabè farmers, intensity fell, breaks lengthened and the fieldwork span increased by approximately 12 minutes per 1°C while approximated physiological strain declined. A separate meta-analysis across occupational settings reported an odds ratio of 4.01 for heat strain during a single shift; this was not a direct comparison of paced and unpaced work. Analysis of 979,759 household observations across 31 countries associated higher temperature with longer water-fetching times. Household obligations appeared to constrain women’s opportunities to pace agricultural work. No study directly linking heat exposure to active travel in an African setting was identified within the search. Heat can extend the time burden of obligatory activity rather than simply reducing participation. Warning-based adaptation should therefore be paired with measures that expand response options, including reliable infrastructure, shade and labour protections. Sustained activity during extreme heat should not be interpreted as resilience without evidence on strain, time burden and capacity to stop.