Effect of NMES+ on Hamstring Lesion (3a/3b)

The goal of this clinical trial is to analyze the effect of the electrical stimulation superimposed onto movement in healthy semi-professional athletes who sustained a type 3a/3b hamstring strain injury. The main questions it aims to answer are: * Is NMES+ useful for the treatment of type 3a/3b hamstring strain injury? * Does NMES+ improve the quality of the injured muscle tissue? Participants will follow a 3 week protocol, following the latest evidence available.\[describe the main tasks participants will be asked to do, treatments they'll be given and use bullets if it is more than 2 items\]. If there is a comparison group: Researchers will compare \[insert groups\] to see if \[insert effects\].