Preseason neuromuscular versus endurance training leads to greater improvements in isokinetic strength, muscle damage, and inflammation parameters in highly trained female soccer players.

BACKGROUND

The preseason offers an opportunity to achieve an optimal level of physical fitness for the entire season. The question arises whether the training programs induce muscle damage and inflammatory processes which may have a negative impact on players' readiness at the beginning of the season.

OBJECTIVES

To examine the effects of a preseason neuromuscular training program (NMT) versus endurance training (ET) on measures of isokinetic strength, muscle damage, and blood parameters in female soccer players.

METHODS

Twenty-two highly trained female soccer players with a mean age of 17.0 ± 1.3 years were randomly assigned to a NMT (n = 11) or ET group (n = 11). NMT and ET programs lasted six weeks with three sessions per week, each 45-60 min. NMT included strength, power, linear sprint and change-of-direction speed, and dynamic stability exercises. ET comprised running, circuit drills, coordination, aerobic circuit, interval-training, speed-endurance exercises, and dynamic stretching. isokinetic knee flexor/extensor parameters (e.g., peak torque) were tested pre- and post-training. Blood samples were analyzed for muscle damage markers: creatine kinase (CK), lactate dehydrogenase (LDH), and inflammation markers: C-reactive protein (CRP), and interleukin-6 (IL-6).

RESULTS

Significant group-by-time interactions were found for all isokinetic parameters (0.001 < p < 0.012, 1.35 < d < 4.17). Post-hoc tests revealed significant improvements following NMT but not ET (0.001 < p < 0.045, 0.81 < d < 2.46). Additionally, there were also significant group-by-time interactions for IL-6 (p = 0.005; d = 0.31), CK (p = 0.026; d = 1.0), and LDH (p < 0.003; d = 1.44). Variations in IL-6, CK, and LDH determined by post-hoc tests indicated decreases in NMT but not ET (IL-6: p = 0.005, d = 1.27; CK: p = 0.023, d = 1.01; LDH: p = 0.002, d = 1.42).

CONCLUSIONS

Six weeks of preseason NMT produced larger improvements in isokinetic strength and less muscle damage and inflammation in highly-trained female soccer players compared to ET group.