(13) RESULTS OF 7-MONTH NEUROMUSCULAR TRAINING PROGRAMME DESIGNED TO IMPROVE THE LEG STIFFNESS IN HIGH-LEVEL YOUNG FEMALE GYMNASTS

Purpose: To examine the responses in relative leg-stiffness (Stiffness_Rel), sprint speed (Speed_peak)and vaulting take-off velocity (TOV) in young female gymnasts following a 7-month neuromuscular training (NMT) intervention.

Methods: Forty-three female gymnasts were allocated into one of three groups; 1) gymnastics + NMT (gNMT; n = 16); 2) gymnastics only (GYM, n = 15); and 3) a maturity-matched control (CON; n = 12). Biological maturation was estimated using percentage of predicted adult height (%PAH) [1]. The gNMT group followed a 7-month NMT program, consisting of 2 x 1-hr sessions/week, in addition to their standard gymnastics training. The GYM group only participated in gymnastics training, while the CON group did not participate in either gymnastics or NMT. Stiffness_Rel, 20 m Speed_peak and vault TOV data were collected at baseline, and after 4- and 7-months of training. A 3 x 3 (group x time) repeated measures ANCOVA (%PAH as a covariate) and Hedges’ g were used to calculate the significance and magnitude of within-group differences [2]. Chi-square analysis was used to evaluate between-group differences for the number of positive responders using 0.6 of the SD (i.e., > moderate worthwhile change (MWC)) for each performance variable. Subsequent thresholds of 0.2 and 1.2 of the between-subject SD were also calculated to reflect smallest- (SWC) and largest-worthwhile change (LWC), respectively.

Results: Significant group x time interactions were present for Stiffness_Rel and Speed_peak. Significant main effects for group were found for all variables, while only Speed_peak demonstrated a main effect for time. Moderate, increases in Stiffness_Rel were shown in the gNMT group between 0-4 (g = 0.66), and 0-7 months (g = 1.03), while the GYM group showed no significant changes (g = 0-16- 0.26), while moderate significant decreases were evident in the CON group (g = 0.74-0.88). No significant changes in sprint speed or vault were present for any group over the study timepoints. Chi square analysis indicated that the gNMT demonstrated significantly more responders (81%) relative to the GYM (33%) and CON (0%) for Stiffness_Rel (figure 1). gNMT trended towards more positive responsiveness as evidenced by both sprint speed and vault TOV (63%).

Conclusion: NMT intervention included with traditional gymnastics training increased Stiffness_Rel to a greater extent than gymnastics training alone, but longer training duration of additive gNMT might be needed to elicit changes in Speed_peak and vault TOV.

PRACTICAL APPLICATIONS: Positive changes in Stiffness_Rel can be achieved in young female gymnasts following supplementary NMT; adaptations that exceed those changes obtained solely from gymnastics training or maturation. Therefore, longer-term, individualised NMT should be considered as a supplement to developmental programs of young gymnasts to elicit positive adaptations in stiffness, speed, and vault performance.

REFRENCES:

[1] Khamis, H.J. & Roche, A.F. Pediatrics 94(4): 504-507, 1994

[2] Hedges, L.V. J Educ Stat 6(2): 107-128, 1981

 


Acknowledgements: None