"The Lake Saint Louis Triathlon has a very happy feel to it," says a regular competitor in the metro area's longest-running triathlon. "The people that live there are out in their front yards giving you water and cheering you on, and the folks who run it are extremely organized. They have everything completely figured out in terms of telling you where exactly you need to be, and when which is not the case at other races." The 750-spot roster is said to fill quickly for the seven-year-old event, which draws contestants from both coasts and is held amid peak Midwestern weather, in early September. Among other perks: an open-water swim in Lake Saint Louis itself (many triathlons involve pool swims), a sloping but scenic bike trail, short and long courses and two scheduled dry runs (useful for the less-experienced and the supercompetitive alike. Race costs run about $100. Heavyweight classes ("Clydesdales" over 200 pounds; "Athenas" over 150) and international distances on the long course (.932 mile swim; 24.85 mile bike; 6.2 mile run) were also recently added.