Cardiovascular and Perceptual Responses to an Ultraendurance Channel Swim: A Case Study.$ An American group has accompanied a swimmer at the Catalin Channel Swim ‘over 32.2 km.The swimmer reached the target after 9 h 2 min at a water temperature of around 19 degrees and an air temperature of almost 19 degrees.
It was a connection between thirst feeling and the remaining floating distance, the perceived effort and heart rate, the perceived effort with the remaining distance as well as the pain sensation and the remaining distance. The very interesting case report can be found under https://pubmed.ncbi.nlm.nih.gov/25819111/