Jakobsen, Markus Due3; Sundstrup, Emil3; Randers, Morten Bredsgaard7; Kjær, Michael8; Andersen, Lars Louis3; Krustrup, Peter9; Aagaard, Per6
1 Department of Exercise and Sport Sciences, Faculty of Science, Københavns Universitet2 Section of Orthopaedics and Internal Medicine, Department of Clinical Medicine, Faculty of Health and Medical Sciences, Københavns Universitet3 Det Nationale Forskningscenter for Arbejdsmiljø4 Department of Clinical Medicine, Department of Clinical Medicine, Faculty of Health and Medical Sciences, Københavns Universitet5 Integrated Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, Københavns Universitet6 Institut for Idræt og Biomekanik, Syddansk Universitet, Odense7 Department of Exercise and Sport Sciences, Faculty of Science, Københavns Universitet8 Department of Clinical Medicine, Department of Clinical Medicine, Faculty of Health and Medical Sciences, Københavns Universitet9 Integrated Physiology, Department of Nutrition, Exercise and Sports, Faculty of Science, Københavns Universitet
The purpose of the present study was to evaluate the effect of contrasting training modalities on mechanical muscle performance and neuromuscular activity during maximal SSC (stretch-shortening cycle) countermovement jumps (CMJ). Bilateral countermovement jumping, surface electromyography (EMG) and muscle fiber size (CSA) were studied in untrained individuals (n=49, 21-45yrs) pre and post 12weeks of progressive heavy-resistance strength training (ST, n=8), recreational soccer training (SOC, n=15), high-intensity interval running (INT, n=7), continuous running (RUN, n=9) or continuation of an inactive life-style (CON, n=10). ST displayed shortened CMJ take-off time (p.70) were observed following ST between training-induced changes in CMJ SSC muscle performance, neuromuscular activity and muscle fiber CSA, respectively. ST induced a more rapid CMJ take-off phase and elevated muscle power production, indicating a more explosive-type SSC muscle performance. No effects were detected in CMJ performance after continuous running, high-intensity interval running and recreational soccer, despite an increased muscle fiber CSA and quadriceps muscle activity in SOC. Enhanced neuromuscular activity in the hip extensors (hamstrings) and plantar flexors, and increased myofiber fiber size were responsible for the enhanced CMJ SSC muscle performance with ST.
Human Movement Science, 2012, Vol 31, Issue 4, p. 970-986