Effects of eccentric- and concentric-based plyometric programmes on strength, speed and tensiomyography parameters of female athletes.

The aim of the study was to examine the effects of eccentric- and concentric-based plyometric programmes on the strength, speed, and tensiomyography (TMG) parameters of female athletes. The study included twenty junior female participants from three different sports equally divided into two experimental groups of n = 10. Two plyometric programmes with contrasting designs were conducted for a period of six weeks, with sessions held twice per week. The first plyometric programme (ECC-CON-G) was based on exercises with eccentric, and the second (CONC-CON-G) with concentric contractions. TMG was used to evaluate neuromuscular performances of six muscles of both legs - vastus lateralis (VL), vastus medialis (VM), biceps femoris (BF), semitendinosus (SM), gastrocnemius lateralis (GL), and gastrocnemius medialis (GM)) - and two strength and speed tests: countermovement jump (CMJ), and sprint test at 10 m and 20 m. The results show that both groups had significant effects between pre-post measurements in CMJ (Diff, ECC-CON-G = 9.02%, and CONC-CON-G = 5.59%, p < 0.05), at 10 m (Diff, ECC-CON-G = 9.23%, and CONC-CON-G = 9.35%, p < 0.001), and 20 m (Diff, ECC-CON-G = 6.16%, and CONC-CON-G = 5.35%, p < 0.001), and TMG parameters in ECC-CON-G (all 6 left leg muscles, and right leg-VL, BF, GL, GM, p < 0.05), in CONC-CON-G (left leg-BF, SM, GL, GM, and right leg-VL, BF, GL, GM, p < 0.05). There were significantly better effects in ECC-CON-G compared to CONC-CON-G for CMJ height and time, for only time in 20 m sprint, and TMG parameters for left leg VL and VM, and right leg BF and GM. A plyometric programme based on exercises with eccentric contractions proved more beneficial for strength, speed, and TMG parameters in young female athletes compared to a programme based on concentric contractions.