research aims : Identifying the muscular strength contribution percentages (fixed, explosive, mobile) in achievement level of 100m sprint-men. Curriculum used: . According to the research problem, nature and goals; the researcher used the descriptive method (surveys) which suit the study nature, to check the hypotheses and adjust the variables related to the study. Research community : The research community included the first year students - boys, faculty of physical education, Assiut university, New Valley branch. The community was 56 student Conclusions: The explosive strength is the most important factors which contribute in the digital achievement level of 100m sprint-men and the muscular strength (fixed, explosive, mobile). Recommendations : Interesting in developing the three types of muscular strength, because they contribute positively in upgrading the digital level of 100m sprint-men.