Aging and Half-Ironman Performance A Canadian group has studied the performance and age of triathlets at the Half-Ironman World Cup in Clearwater, Florida, from 2006-2010.Over this period, the times in cycling and run faster, but not in swimming. Men were usually faster than the women, the difference vary depending on the age group.
The benefit was already in progress in the age group 35-39 years, while in swimming until the age group 50-55 remained quite constant. The results can be found under https://pubmed.ncbi.nlm.nih.gov/28230417/