Effects of a Low-Volume Kettlebell Strength Program on Vertical Jump and Isometric Strength in Dancers: A Pilot Study

Objectives: The jumping ability and strength of the lower limbs in dancers are fundamental to their artistic performance. Similarly, the correct placement of the various leg positions, such as parallel and dehors, are essential aspects of dance technique. We aimed to analyze the effectiveness of a modified strength program on jumping capacity in parallel and dehors, and to assess whether this type of training improves the isometric strength of dancers. Methods: An experimental research study was conducted with pre- and post-intervention assessments on a group of nine semi-professional dancers (seven women and two men) (X = 20 years and DT = 6.67), with an average weight of 62.12 ± 7.38 kg and a height of 1.67 ± 0.05 m. Body composition, isometric strength in the lower limbs, and vertical jump capacity with feet in parallel and in the dehors position were analyzed. The "Simple and Sinister" kettlebell training protocol was implemented, reducing the number of sessions and the duration of the program while incorporating a progression in load. Results: Significant changes were observed in both the parallel jump and the dehors position; however, body composition and isometric strength, although showing higher values at the end of the intervention for all variables, did not demonstrate significant improvements. Thus, while in the pre-intervention phase, jump capacity was associated with multiple variables, in the post-intervention phase, an inverse association was found only with the percentage of body fat. Conclusions: A 12-week training program with two sessions per week is sufficient to achieve significant changes in the jumping ability of dancers, but not in the isometric strength of the lower limbs.