Effects of resistance training in humans on neck muscle performance, and electromyogram power spectrum changes.
The purpose of this study was to quantify the neuromuscular cervical adaptations to an 8 week strength training programme. Seven healthy men, with no pathological conditions of the neck, performed a lateral flexion isometric resistance-training programme three times a week. The training sessions consisted of one set of ten contractions, each of 6 s duration, at 60% of the predetermined maximal voluntary isometric torque (MVTim) (warm-up) and two sets of eight contractions, each of 6 s duration, at 80% MVTim. The training effects were evaluated in three ways: muscle size, strength and fatigability. The cross-sectional areas (CSA) of the trapezius (TRP) and sternocleidomastoideus (SCM) muscles were determined using a computerised tomographic scanner. Results showed an increase in the CSA of TRP and SCM muscles after training, 8.8% at C5 level and 6.4% at C7 level for SCM muscle and 12.2% at C7 level for TRP muscle. Strength increased significantly under both isometric and isokinetic conditions (35% and 20%, respectively). Muscle fatigability in lateral flexion was quantified during a sustained isometric contraction at 50% of MVTim. The shift of the mean power frequency of the electromyogram power spectrum density function of SCM muscle toward lower frequencies was less after training (14.6% compared to 6.8%). These results indicate the beneficial effect of a strength-training programme which increases neck muscle size and strength during lateral flexion, and decreases the fatigability of the superficial muscles of the neck.
Portero
P
P
Institut de Myologie, Groupe Hospitalier Pitié-Salpêtrière,  Paris, France. p.portero@myologie, chups.jussieu.fr
Bigard
A X
AX
Gamet
D
D
Flageat
J R
JR
Guézennec
C Y
CY
D000328:Adult; D004576:Electromyography; D015444:Exercise / Q000502:physiology*; D006801:Humans; D007551:Isotonic Contraction / Q000502:physiology*; D008297:Male; D018763:Muscle Fatigue / Q000502:physiology; D009334:Neck Muscles / Q000033:anatomy & histology / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology; D014057:Tomography, X-Ray Computed