Born in Cienfuegos, she was among the first athletes to enrol in the new national athletics program established after the end of the Cuban Revolution in 1959. Her talent for running was noticed at high school and she transferred to a school in Havana to focus on sports in 1961. Among her contemporaries were sprinters Aurelia Pentón, Fulgencia Romay, and Miguelina Cobián. Her first international selection came at the age of fifteen and she managed fourth place in the long jump at the 1962 Central American and Caribbean Games. She rose to prominence the following year – at the 1963 Pan American Games in São Paulo she took fifth in the long jump and helped set a Cuban record in the 4 × 100 metres relay of 46.44 seconds alongside Romay, Cobián and Nereida Borges. She added to this with a fourth-place finish in the long jump and a relay bronze at the 1963 Summer Universiade. That year she achieved her first national record in the long jump, clearing in June, then improving further to one week later. Her fourth national record of the year came that December, as she was part of a Cuban relay quartet that ran 46.2 seconds.
Regional champion
Despite being the country's best jumper, Martínez was not selected for the 1964 Tokyo Olympics on account of her young age. That year, she improved the Cuban long jump record on five occasions, beginning with a jump of in April and ending with a clearance of in November. She struggled to improve in the 1965 season, managing a best of, but set a lifetime best in the 100 metres with a time of 11.8 seconds. Martínez became the first woman from the Central America and Caribbean region to surpass six metres for the long jump, doing so with a jumps of then at a meeting in Havana in April 1966. Her first major individual success followed at the 1966 Central American and Caribbean Games, where she succeeded fellow Cuban Díaz to the women's long jump title with a Games record of. The 21-year-old won the third major international relay medal of her career, taking the silver with the Cuban women behind a Jamaican team led by 200 metres champion Una Morris. Martínez had a very patriotic approach to the competition and held up her performance as a tribute to her country – her greatest memory of the period was of Fidel Castro signing her two medals. The best performances of her career were in the 1967 season. In June she improved the Cuban national record for the tenth time with a jump of in Budapest. At the 1967 Central American and Caribbean Championships in Athletics she became the first women's long jump champion with a result of, narrowly beating her compatriot Garbey – Marina Samuells and Garbey would turn Martínez's 1967 win into a four-edition streak of wins for Cuba. Cuba took a sweep of the women's titles at the event held in Mexico.
American gold and late career
Martínez was chosen for the 1967 Pan American Games and she came up against the defending champion, Willye White of the United States. White produced a jump of – two centimetres further than her winning jump four years earlier. However, that mark was not sufficient as Martínez produced the best jump of her life at. This was a Pan American Games record and good 13 cm clear of runner-up Gisela Vidal. The pre-event favourite, American Martha Watson, did not make the podium. Martínez's performance made her the first ever Cuban athlete – male or female – to win a Pan American gold medal in a jumping discipline. Cuba has since gone on to produce numerous world class jumpers, such as world record holder Javier Sotomayor, four-time long jump world champion Iván Pedroso and double triple jump world champion Yargelis Savigne. She hoped to be selected for Cuba at the 1968 Summer Olympics, but did not receive a call-up to compete. The selectors requested that she be part of the team as an alternate for the 4 × 100 metres relay, but she refused due to her damaged pride of not being selected individually – a decision she regretted later in life. She produced marks of and in the 1969 and 1970 seasons, but she retired at age 24, having failed to recapture her best form. After retiring from competition she went into academia and became a professor of physical education at the Instituto Técnico Militar in Havana. She remained in the role for almost 30 years. She died in April 2014 and was buried at Colon Cemetery, Havana, alongside other Cuban female athletes.
