One in eight females face the diagnosis of breast cancer in their life time (Eisemann et al, 2013) and it is the most prevalent of female cancer cases worldwide accounting for 46 per cent (Campbell et al, 2012). With drastic improvements in detection and treatment of breast cancer, five-year survival rates have substantially improved reaching 86 per cent and increasing (Bower et al, 2005). However, due to the extensive treatment they endure, survivors face an array of negative side effects, with the most common reported to be: persistent fatigue, hot flashes and night sweats (Fisher et al, 2013). Hot flashes represent an excessive reflex response to changes in the temperature control circuit, and although not fully understood yet, are proposed to be the result of thermoregulatory and neurochemical disruptions (Carpenter, 2005). There is a vast amount of literature assessing different interventions to reduce the severity and quantity of hot flashes, varying from pharmaceutical drugs to acupuncture and relaxation therapy, with varied success (Johns et al, 2016). There is, however, no assessment of the underlying thermoregulatory dysfunction occurring, or interventions focusing on this, for example, cooling or hydration strategies. Therefore, the aim of this PhD is to examine and characterise the exercising thermoregulation of breast cancer survivors versus age-matched controls, to identify if survivors are more heat sensitive. The studies following will then investigate the most effective and practical interventions to reduce this heat sensitivity and therefore the risk of heat-related illnesses to improve their quality of life.