Introduction: Isometric training is related to the maintenance of muscle contraction and length, which has been transferred to the physical and sports field. Objective: To analyze and describe the effects of isometric training in the field of physical and sports performance. Methods: The narrative review was developed in combination with the methodologies described by Kart & Kart, and Castillo-Paredes et al, through the search strategy with the following keywords and Boolean operators; ("Young adults") OR ("Adults") AND ("isometric exercise") OR ("Isometric Strength Training") OR ("isometric resistance exercise") AND ("perfomance") OR ("strength") OR ("power") OR ("fitness") in three databases (PubMed, Scopus and WoS). A total of 14 investigations were identified that provided answers to the search strategy. Results: The results showed significant improvements in the rate of calf muscle strength development in the experimental group, highlighting the importance of personalized training. In addition, significant differences in muscle strength were observed between volleyball players and a control group, highlighting the relevance of assessing muscle strength to improve performance and prevent injury. Conclusions: Finally, the importance of designing isometric training programs in a personalized manner, considering the specificity of the exercise and the individual characteristics of the subjects is emphasized. The reliability of tests such as isometric squat and isometric muscular endurance tests is highlighted, underlining the relevance of isometric training in health and sports performance.