Because of the increased use of fitness devices by untrained subjects, the lack of scientific evidence on the devices, and the effects that poor execution of movements can have in terms of musculoskeletal injuries, this article presents a study of the physical activity performed on the Five Minutes Shaper fitness training device by means of a kinematic analysis in untrained users. The study outlines the features of the kinematic variables of velocity, acceleration, and joint amplitude that have to do with the movement of three of the six levels of the device -easy, medium, extreme- on the knee and hip joints. In addition, we performed a test of statistical significance in order to evaluate the effects of the different levels that were analyzed in the device on the kinematic variables in men and women. Motion digitization was also performed by means of an optical motion capture system; the kinematic analysis by means of the Kinovea and Matlab software, and the statistical analysis by means of the SPSS software. A group of five men and five women who met the inclusion criteria took part in the experiments. The results present a kinematic characterization between genders that do not have physical conditioning for the movement of the two joints, as well as for each of the levels analyzed in the Five Minutes Shaper device. The study focuses on the knee and hip joints, since these are the main axes of movement.
