naa a22 4500 569311624 20190727060926.0 cr unu---uuuuu 190727e20190319xx s 000 0 eng 10.3929/ethz-b-000355112 doi 10.3389/fphys.2019.00229 doi (ETHRESEARCH)oai:www.research-collection.ethz.ch:20.500.11850/355112 Beyond RPE: the perception of exercise under normal and ketotic conditions [Elektronische Daten] [Olivia K. Faull, David J. Dearlove, Kieran Clarke, Pete J. Cox] Open access ethresearch Aim: Subjective perceptions of exercising exertion are integral to maintaining homeostasis. Traditional methods have utilized scores of ‘rating of perceived exertion' (RPE) to quantify these subjective perceptions, and here we aimed to test whether RPE may encompass identifiable localized perceptions from the lungs (breathlessness) and legs (leg discomfort), as well as their corresponding measures of anxiety. We utilized the intervention of ketoacidosis (via consumption of an exogenous ketone ester drink) to independently perturb exercise-related metabolites and humoral signals, thus allowing us to additionally identify the possible contributing physiological signals to each of these perceptions. Methods: Twelve trained volunteers underwent two incremental bicycle ergometer tests to exhaustion, following ingestion of either an exogenous ketone ester or a taste-matched placebo drink. Cardiorespiratory measures, blood samples and perceived exertion scales were taken throughout. Firstly, two-way repeated-measures ANOVAs were employed to identify the overall effects of ketoacidosis, followed by generalized linear mixed model regression to isolate physiological predictors contributing to each perception. Results: Rating of perceived exertion was found to contain contributions from localized perceptions of breathlessness and leg discomfort, with no measurable effect of ketoacidosis on overall exertion. Leg discomfort, anxiety of breathing and anxiety of leg discomfort were increased during ketoacidosis, and correspondingly contained pH within their prediction models. Anxiety of leg discomfort also encompassed additional humoral signals of blood glucose and ketone concentrations. Conclusion: These results indicate the presence of localized components of RPE in the form of breathlessness and leg discomfort. Furthermore, subjective perceptions of anxiety appear to result from a complex interplay of humoral signals, which may be evolutionarily important when monitoring exertion under times of metabolic stress, such as during starvation. Creative Commons Attribution 4.0 International http://creativecommons.org/licenses/by/4.0 ethresearch Exercise ethresearch Perception ethresearch RPE ethresearch Ketoacidosis ethresearch Anxiety ethresearch Faull Olivia K. joint author Dearlove David J. joint author Clarke Kieran joint author Cox Pete J. joint author Frontiers in Physiology Lausanne : Frontiers Research Foundation 10, p. 229 1664-042X http://hdl.handle.net/20.500.11850/355112 text/html WWW-Backlink auf das Repository (Open access) 1 Journal Article ethresearch ETHRESEARCH 856 40 http://hdl.handle.net/20.500.11850/355112 text/html WWW-Backlink auf das Repository (Open access) ETHRESEARCH 700 1- Faull Olivia K. joint author ETHRESEARCH 700 1- Dearlove David J. joint author ETHRESEARCH 700 1- Clarke Kieran joint author ETHRESEARCH 700 1- Cox Pete J. joint author ETHRESEARCH 773 0- Frontiers in Physiology Lausanne : Frontiers Research Foundation 10, p. 229 1664-042X BK010053 XK010053 XK010000 ETHRESEARCH ETHRESEARCH ETHRESEARCH Journal Article Open access