For the first half of the 1960s Melesio Soto represented Mexico in international cycling competitions. After finishing ninth overall at the Tour of Mexico in 1961, Soto then won gold in the 4,000 metres team pursuit and bronze in the team road race at the 1962 Central American and Caribbean Games in Kingston, Jamacia. He continued his success in the 4,000 metres team pursuit, winning bronze with Mauricio Mata, Jacinto Brito, and Enrique Barajas at the 1963 Pan American Games in São Paulo. Soto’s form earned him a place on the Olympic team for the 1964 Games in Tokyo, where he placed 93rd in the road race, only 0.2 seconds behind the race winner.