A long-distance runner (5,000 m and 10,000 m), Ramjohn was the first to win a gold medal for Trinidad and Tobago at a major athletics event, the CAC Games in 1946. He was also part of the first group of five athletes to represent Trinidad and Tobago in the Olympic Games (1948). Between 1936 and 1951 he achieved 96 victories, 40 second-place and 13 third-place finishes.
Ramjohn joined the Fifth Naparima Scout Troop in 1930 and in 1937 he was elevated to King Scout and Patrol Leader. In this capacity he was one of 12 representatives from Trinidad and Tobago at the coronation of King George VI and Queen Elizabeth. He remained involved in the Scouting movement for the remainder of his life. Ramjohn was awarded the Humming Bird Medal (Silver) for Social Work and Sport by the government of Trinidad and Tobago. In 2000 the Manny Ramjohn Stadium, a new football and athletics stadium at Union Park, Marabella was named in his honour.
Ramjohn's career included the following significant accomplishments:
- 1948 - Wood Badge, The Scout Association of the United Kingdom
- 1973 - Medal of Merit, The Scout Association of Trinidad and Tobago
- 1979 - Silver Ibis Award for meritorious service, The Scout Association of Trinidad and Tobago
- 1980 - Silver Platter 50-Year Award, Point-a-Pierre District Scouts Association
- 1982 - Trinidad and Tobago Humming Bird Medal Silver for Social Work and Sport
- "Former Olympic runner dies at 82"; Josie-Ann Carrington, Trinidad Express, 31 January 1998 at the Wayback Machine (archived October 14, 2006)
- Mannie Ramjohn from bestoftrinidad.com
- "Manny Ramjohn Memorial Games: Tribute to T&T's first Golden Boy", Mervyn Stewart, Trinidad Express, 20 May 2004 at the Wayback Machine (archived October 10, 2007)
- Evans, Hilary; Gjerde, Arild; Heijmans, Jeroen; Mallon, Bill; et al. "Manny Ramjohn". Olympics at Sports-Reference.com. Sports Reference LLC. Archived from the original on 2020-04-18.