His father, born at La Plaine Saint-Denis [fr] in France, fought in the International Brigades during the Spanish Civil War in 1936.

[11] In this respect, he negotiated with the employers within the scope of the reorganisation of the automotive industry, thus showing his ability to discuss by containing the most radical elements of his union.

Martinez was elected general secretary of the CGT[6] by the National Confederal Committee on 3 February 2015, with 93.4 percent of the vote,[4] and was confirmed to that position by the congress of Marseille in April 2016, after he travelled across France during one year to meet the local sections of the union to strengthen his popularity.

To take account of the growing influence of the ultra-left in the union, Martinez took on a hard line of struggle against employers and liberalism, notably against the Valls government by demanding the withdrawal of the 2016 Labour reform bill, to which the CGT became the main opponent.

[8] Demonstrations were accompanied by blockades of refineries, repetitive strikes in the transport sector, and stoppage of nuclear power plants, which threatened the smooth running of the UEFA Euro 2016 in France.

[20][21][22] Faced with the internal oppositions and the decreasing importance of the CGT in the staff representatives elections, this anti-establishment opinion could enable the union to unify the militants and draw benefit from the left-wing voters' dissatisfaction toward the Socialist Party government.

[27] When he was elected the general secretary of the CGT, Martinez proposed to reduce the weekly work time to 32 hours to enable the creation of four million new jobs.