Featured Application Community-based classes with musical support are among the most common forms of physical activity practice for recreational users of fitness centers. Thus, fitness professionals need to know the effects on the body of these activities. For this reason, this study investigated the short-term benefits of practicing the Body Jump(R) program on physical fitness and body composition in a group of young and healthy active women. (1) Background: Body Jump(R) is a novel group fitness program with musical support, which is performed rebounding in a minitrampoline. Although the number of practitioners has increased exponentially in recent years, this activity's short-term effects on physical fitness and body composition in women have not yet been studied. (2) Methods: 27 healthy young women were randomly divided into a Body Jump(R) group (BJ) and a control group (CG). BJ performed three classes per week for one month. The week before and after the intervention, the anthropometric assessments were carried out to estimate the body composition, and different performance tests were performed to assess the jumping capacity (countermovement jump (CMJ) and squat jump (SJ) tests), the muscular strength (1RM test) and the aerobic fitness (UKK test). (3) Results: VO2 max (p = 0.001), CMJ flight height (p = 0.023), SJ flight height (p = 0.003) and the 1RM value in the half-squat exercise (p = 0.009) were significantly increased in BJ. In CG, there were no statistically significant differences after the intervention period. Regarding the changes in body composition, a significant enhancement in several parameters were found in BJ, such as the sum of skinfolds (p = 0.003) and the percentage of fat mass (p = 0.002), while no changes were found in any of the anthropometric variables in CG. (4) Conclusions: carrying out the Body Jump(R) program three days per week for one month had positive effects on physical fitness and body composition in a group of healthy young women. This training program can be an effective option for enhancing, in the short term, these fitness parameters and the body composition of these recreational users into the fitness centers.