Abstract
1/2026
vol. 43
Original paper
Effect of plyometric training based on the integral reactive strength index of national-level jumpers and sprinters. A randomized crossover trial
- University of Coimbra, Faculty of Sport Sciences and Physical Education, 3040-256 Coimbra, Portugal
- CIPER, University of Lisbon, Faculty of Human Kinetics, Cruz Quebrada, Dafundo, Portugal
- ISCE—Polytechnic University of Lisbon and Tagus Valey, Department of Sport Sciences, 2620-379 Lisbon, Portugal
- Live Quatity Research Center (LQRC), Complexo Andaluz, Apartado 279, 2001-904, Santarém, Portugal
- University of Sport Sciences (UCCFD). Manuel Fajardo, 10600, Havana, Cuba
Biol Sport. 2026; 43: 127–138
Online publish date: 2025/08/06
The Integral Reactive Strength Index (IRSI) has recently been described in the literature as a new indicator that normalizes the reactive strength index based on fall height. This study aimed to compare the effects of a plyometrictraining program based on IRSI versus a traditional jump training program on spatiotemporal variables associated with the performance of national-level jumpers and sprinters. A randomized, crossover trial with three parallel groups was conducted. Twenty-seven male track and field athletes were divided into three groups. The G-RT1 group consisting of 9 participants, began the experiment with IRSI based training as the load prescription criterion. The G-PT2 group consisting of 10 participants, started the experiment with traditional plyometric training, and the control group, G-CT3, consisting of 8 participants, continued its usual training. After 19 weeks, a two-way mixed analysis of variance for the G-RT1 group found a significant interaction and large effect sizes (ES) in the group-time relationship in the 60 m dash (p ≤ 0. 001; f = 101.2; η2 = 0.089), and the standing triple jump (STJ) (p ≤ 0.001; f = 119.8; η2 = 0.031). The G-PT2 also showed better results, but the ES was lower for the standing long jump (p ≤ 0.001; f = 52.7; η2 = 0.045), and the STJ (p ≤ 0.001; f = 22.7; ηp2 = 0.011). Meanwhile, the G-CT3 did not show significant improvement at the end of the program. It is concluded that the IRSI-based plyometric training program produces better results than the traditional program. The use of IRSI-based improves individualization, emphasizes high-intensity maintenance, and induces better results with less training volume.
Keywords
Intensity, Volume, Reactive Capacity, Drop Jump, Jump training program
Integrated with
