Heat sensitivity in people with MS is well documented. However, the underlying physiological mechanisms are still unclear. This project will support Ms Chaseling in her PhD studies to investigate how MS impairs human body temperature regulation, and determine whether increases in ambient temperature make people with MS more heat sensitive during exercise. Furthermore, Ms Chaseling will also investigate the effects of cold fluid ingestion on heat regulation during exercise.
Phase 1 of Ms Chaseling’s project will assess impairments in heat regulation in individuals with MS during physical activity in the heat. To assess this, measurements of skin blood flow, sweat rate, core and skin temperature will be used to derive information regarding body temperature regulation. In phase 2, responses to thermal sensations will be measured at rest and compared against responses to the same stimuli during physical activity in the heat. Phase 3 of this study will assess the influence of ingesting a cold drink during physical activity in the heat, and the potential physiological effects on sweat rates, core temperature and the subsequent effect on subjective whole body thermal sensation.
This research will broaden the understanding of heat regulation in the MS population, and the application of this research will assist in the management of heat-related fatigue experienced by individuals with MS. This project will inform the development of clinical guidelines for safe levels of exercise in people with MS.
In her studies, Ms Chaseling compared the various biological measurements in people with and without MS, who were made to exercise in a warm environment achieved using temperature controlled rooms. Results showed that people with MS do not seem to have an altered response to heat, and disproved the notion that core temperature is elevated in people with relapsing-remitting MS, contributing to fatigue.
Following on from these findings, Ms Chaseling went on to investigate the influence of ingesting a cold drink during physical activity in the heat. She found that people with MS have a different perception of cold than those without MS, and demonstrated that people with MS tolerated the heat much better when exercising in a warm environment with the ingestion of a cold drink. Ms Chaseling also discovered that a cold drink could improve exercise tolerance by up to 30% in people with MS, independent of other factors such as core and skin temperatures. More studies are currently underway to further investigate the altered thermal sensation discovered in people with MS, which will determine if this is due to biological changes alone, or whether psychological perceptions also play a role.
This work has provided evidence to support an easily applicable cooling strategy for mitigating heat intolerance in MS, and provides insights into the potential role of receptors in the stomach and mouth in alleviating the heat sensitivity experienced by people with MS when exercising in hot environments.
Ms Chaseling has presented her findings at seven international and one national conference, and one of her publications has been selected as an Editor’s Pick for April 2018 in the top ranked journal of exercise science.
Updated: 31 March 2019
Updated: 10 January, 2016