An 1981 inductee in the International Marathon Swimming Hall of Fame, Claudio Plit won major international marathon races for over three decades. He has competed in the prestigious Traversée internationale du lac St-Jean over 25 times, winning 4 times.
In 1985, 1986, 1987, 1988 and 1989, Traversées internationale du lac St-Jean was a double-crossing rather than a single crossing of lac St-Jean in Quebec. Plit was undefeated in these four 64K swims in close races with Philip Rush of New Zealand in low 60ºF waters (15ºC-17ºC), the most memorable being the 1986 victory where Plit outlasted Rush 17 hours 45 minutes 24 seconds to 17 hours 46 minutes 29 seconds.
Plit has won every major marathon race around the world. He swam 17 Traversées internationale du lac Memphremagog from Vermont to Canada, winning once. He swam 15 Maratonas del Golfo Capri-Napoli in Italy, winning 4 times. He swam the 14 Maratón Acuática Internacional Santa Fe-Coronda, winning 4 times. He swam 20 Atlantic City Around-the-Island Marathons Swim, the 88K Hernandarias–Parana Marathon in Argentina and crossed the English Channel twice.
Most impressively and very consistently, he swam in 250 international swimming events averaging 8 hours.
He is currently the meet director for the Mar de Plata and Maratón Acuática Internacional Cuidad de Rosario, both in Argentina. Claudio remains also active as a coach and escorts swimmers participating on the FINA professional circuit and been a guest presenter at FINA open water seminars.