Functional maximal strength training induces neural transfer to single-joint tasks.
The purpose of this study was to investigate whether neural adaptations following functional multiple-joint leg press training can induce neural adaptations to the plantar flexor muscles in a single-joint contraction task. Subjects were randomised to a maximal strength training (MST) (n = 10) or a control group (n = 9). MST consisted of 24 sessions (8 weeks) of 4 x 4 repetitions of horizontal leg press using maximal intended velocity in the concentric phase with the movement ending in a plantar flexion. Neural adaptations in the soleus and gastrocnemius medialis (GM) were assessed by surface electromyographic activity and V-waves during maximum voluntary isometric contraction (MVIC), and also by H-reflexes in the soleus during rest and 20% MVIC. One repetition maximum leg press increased by 44 +/- 14% (mean +/- SD; P < 0.01). Plantar flexion MVIC increased by 20 +/- 14% (P < 0.01), accompanied by 13 +/- 19% (P < 0.05) increase in soleus, but not GM surface electromyography. Soleus V/M(SUP) increased by 53 +/- 66% and in GM by 59 +/- 64% (P < 0.05). Normalised soleus H-reflexes remained unchanged by training. No changes occurred in the control group. These results suggest that leg press MST can induce neural adaptations in a single-joint plantar flexion MVIC task.
Fimland
Marius S
MS
Department of Circulation and Imaging, Norwegian University of Science and Technology, Trondheim 7489, Norway. marius.fimland@ntnu.no
Helgerud
Jan
J
Gruber
Markus
M
Leivseth
Gunnar
G
Hoff
Jan
J
D000843:Ankle Joint / Q000294:innervation* / Q000502:physiology*; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D053580:Muscle Strength / Q000502:physiology*; D009473:Neuronal Plasticity / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D010809:Physical Fitness / Q000502:physiology*; D055815:Young Adult