Heat Reactions To Acute Exercise In Female Breast Cancer Survivors (PhD)

Description

This thesis aimed to take a multidisciplinary approach in the assessment of female breast cancer survivors’ (BCS) responses to acute exercise under different thermal environments. Heat reactions can be reflected through core and skin temperature and sudomotor (sweat) responses. This thesis began with a technical approach to identify an array of sweat analysis techniques’ (whole body sweat rate, local sweat rate and sweat conductivity) reliability in a female population. A newly developed wearable sweat rate monitor was included in this reliability study to establish local
sweat rate in real-time. The use of these sweat techniques was deemed appropriate and practical in females when exercising at a moderate intensity under heat stress conditions. Study 2 assessed the validity of the wearable sweat rate monitor and the routine sweat analysis techniques, which were deemed reliable in Study 1. Construct validity was determined utilising a 5-day short-term heat acclimation intervention that demonstrated significant phenotypic adaptation across classic physiological markers (core temperature and heart rate). Importantly, sudomotor function significantly adapted across the sweat analysis techniques employed and therefore, all markers were deemed sensitive to adaptation, reinforcing their validity. Data collection for both Study 3 and 4 was simultaneous. Study 3 incorporated all the above techniques, alongside physiological, inflammatory and perceptual markers to assess heat reactions in
female BCS when compared to healthy age-matched females. An acute exercise intervention that replicated the daily recommended exercise guidelines (30-minutes moderate intensity exercise) followed by a self-paced functional performance test (6-minute walk test) was employed, in both warm (25°C, 50%RH) and hot conditions (35°C, 50%RH). There was no compromise in any inflammatory or perceptual parameters between BCS and controls. All physiological markers were higher during the 35°C vs. 25°C trial; Tre (~0.25°C, p < 0.01), Tskin (~3.8°C, p, p0.05). Both groups covered a greater 6MWT distance in 25°C vs. 35°C (by ~20m; pTaken together, evidence in this thesis supports the notion that BCS are not disadvantaged when participating within government daily exercise recommendations in both warm and hot environments. This research, amongst the abundance of literature promoting regular physical activity for reduced cancer recurrence and many other health benefits, seeks to educate and motivate this population to be active. To conclude, the results of this thesis aim to be the foundation for further investigation of this population, where currently there is sparsity of research into their physiological responses to exercise, and especially when under heat stress conditions.

Period	3 Oct 2022
Examinee	Rebecca Relf
Degree of Recognition	National