TY  - JOUR
A1  - Lesinski, Melanie
A1  - Prieske, Olaf
A1  - Beurskens, Rainer
A1  - Behm, David George
A1  - Granacher, Urs
T1  - Effects of drop height and surface instability on neuromuscular activation during drop jumps
JF  - Scandinavian journal of medicine & science in sports
N2  - The purpose of this study was to examine whether drop height-induced changes in leg muscle activity during drop jumps (DJ) are additionally modulated by surface condition. Twenty-four healthy participants (23.7 +/- 1.8years) performed DJs on a force plate on stable, unstable, and highly unstable surfaces using different drop heights (i.e., 20cm, 40cm, 60cm). Electromyographic (EMG) activity of soleus (SOL), gastrocnemius (GM), tibialis anterior (TA) muscles and coactivation of TA/SOL and TA/GM were analyzed for time intervals 100ms prior to ground contact (preactivation) and 30-60ms after ground contact [short latency response (SLR)]. Increasing drop heights resulted in progressively increased SOL and GM activity during preactivation and SLR (P<0.01; 1.01 d 5.34) while TA/SOL coactivation decreased (P<0.05; 0.51 d 3.01). Increasing surface instability produced decreased activities during preactivation (GM) and SLR (GM, SOL) (P<0.05; 1.36 d 4.30). Coactivation increased during SLR (P<0.05; 1.50 d 2.58). A significant drop heightxsurface interaction was observed for SOL during SLR. Lower SOL activity was found on unstable compared to stable surfaces for drop heights 40cm (P<0.05; 1.25 d 2.12). Findings revealed that instability-related changes in activity of selected leg muscles are minimally affected by drop height.
KW  - Stretch-shortening cycle
KW  - EMG
KW  - preactivation
KW  - short latency response
Y1  - 2017
U6  - https://doi.org/10.1111/sms.12732
SN  - 0905-7188
SN  - 1600-0838
VL  - 27
SP  - 1090
EP  - 1098
PB  - Wiley
CY  - Hoboken
ER  -