A substantial amount of attention has been devoted towards the potential sport legacy of the Olympic Games. In spite of the increasing academic interest in this topic, there is a knowledge gap as far as sport legacy is concerned by types of different sports. The authors bridge this gap by analysing the evolution of 43 different Olympic/Paralympic sport modalities in the two-year period after the London 2012 Olympics. By using data from the Active People Survey with a sample of 165,000 people annually, and considering some demographic variables and the effect of the economic environment, the paper aims to test the existence of a sport legacy. We have applied time series analysis and ARIMA models for controlling for economic influence and seasonal adjustment and for making comparisons among participation rates. The results show, for the total of the sports analysed, that there were 336,000 individuals who increased their frequency of participation, while there was no significant increase in the number of new participants in these sports. When we develop the analysis for types of sports, London 2012 is positively associated not only with the frequency of participation in some types of sport but also with an increase in the number of new sport participants. Gender and age differences are also detected. The results show the differences of sport legacy by type of sports. Moreover, this research has elucidated an important unrecognised aspect of the effect of the Olympic Games and perhaps major events: that they can become a major policy tool for reversing sporting inequalities.