JOURNAL WATCH

Increased H-reflex response induced by intramuscular electrical stimulation of latent myofascial trigger points. Ge H-Y, Serrao M, et al. Acupuncture in Medicine 2009;27:150-154 (full article available)

H-reflex latency and the conduction velocity were first

determined from electrical stimulation of the tibial nerve in 13 healthy subjects. Then an intramuscular monopolar needle electrode was inserted randomly into a latent MTrP or a non-MTrP in the gastrocnemius muscle. Electrical stimuli at different intensities were delivered via the intramuscular recording electrode to the MTrP or non-MTrP. The average conduction velocity of the electrical stimulation of tibial nerve was similar with the conduction velocity of intramuscular electrical stimulation. The intramuscular H-reflex at

MTrPs was higher in amplitude than non-MTrPs. The reflex threshold was lower for MTrPs than non-MTrPs.

sportEX comment This takes us a step closer to

discovering what is going on by providing us with the first electrophysiological evidence that intramuscular electrical stimulation can evoke H-reflex, and that higher H-reflex amplitude and lower H-reflex threshold exist at MTrPs than non-MTrPs respectively, suggesting that muscle spindle afferents may be involved in the pathophysiology of MTrPs.

Compression on trigger points in the leg muscle increases parasympathetic nervous activity based on heart rate variability. Takamoto K, Sakai S et al. Journal of Physiological Sciences 2009;59(3):191-197 (full article available)

This study investigates how

compression applied over trigger points (TPs) affects the autonomic nervous system. After a day’s work, predominantly in a standing position, six adult females, were asked to rest supine and electrocardiograms (ECGs), instantaneous lung volume (ILV) and systolic and diastolic blood pressures (SBP, DBP) were measured, before and after pressure application over the TPs in the lower limb muscles where the subjects felt muscle fatigue or discomfort. They were also asked to coordinate breathing with beeping sounds in order to regulate it. The therapeutic effects of TP compression were assessed by a subjective fatigue scale. Parasympathetic nervous activity was also assessed by spectral analysis of heart rate (HR) variability. The transfer function from ILV to

HR was evaluated using linear analysis. The results indicated that TP compression (1) decreased HR, SBP and DBP, (2) increased parasympathetic activity, (3) increased the gain from ILV to HR, and (4) improved the fatigue scores. These findings suggest that an increase in parasympathetic nervous activity after the TP compression induced a reduction of fatigue.

sportEX comment This paper uses the term,

‘massotherapy’, to indicate the therapeutic use of massage to treat various chronic pain syndromes which actually isn’t a bad term. It certainly gets us away from the seedier connotations of ‘massage’. The trouble with these findings is that some or all of the results might be down to regulating the breathing.

Time course of changes in muscle and tendon properties during strength training and detraining. Keitaro K, Ikebukuro T et al. Journal of Strength and Conditioning

Research: 2010;24(2):322-331

Eight subjects completed three months of isometric knee extension training followed by detraining for another three months. At beginning and at monthly intervals muscle strength, neural activation level, muscle and tendon cross-sectional areas (CSA), and tendon stiffness were measured. Training increased muscle strength and

neural activation level by 29.6 and 7.3% after 2 months and by 40.5 and 8.9% after three months. Muscle CSA and tendon stiffness did not change until two months of training period, and afterward, the increases in muscle CSA and tendon stiffness reached statistical significance at the end of training. During detraining period, muscle strength and neural activation level did not change, although muscle CSA and tendon stiffness decreased to pre-training level at one and two months of detraining, respectively.

sportEX comment Let’s not get too carried away because this was only a very small

study involving one group of muscles. It confirms that morphological changes lag behind those of strength and neural activity in the short term and that these disappear first. However the strength gained in three months remained after the three month detraining period so the big question (if this repeats across other muscle groups), is how can this be incorporated into the periodisation of a training plan?

Changes in psychological parameters in patients with tension-type headache following massage therapy: A pilot study. Moraska A, Chandler C. Journal of Manual and Manipulative Therapy 2009;17(2):86-94

The objective of this pilot study was to assess the value of a structured massage therapy programme, with a focus on myofascial trigger points, on psychological measures associated with tension-type headache. Eighteen subjects with episodic or chronic tension-type headache were enrolled. Twice weekly, 45-minute massage therapy sessions commenced following the baseline phase and continued for 6 weeks

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with evaluation at 3-week intervals using the State-Trait Anxiety Inventory, Beck Depression Inventory, and the Perceived Stress Scale. The Daily Stress Inventory was administered over 7-day periods during baseline and the final week of massage. A significant improvement in all psychological measures was detected over the timeframe of the study. Post hoc evaluation indicated improvement over baseline for depression and trait anxiety following six weeks

of massage, but not 3 weeks. A reduction in the number of events deemed stressful as well as their respective impact was detected.

sportEX comment Morska is one of the top researchers in the field of massage and here we have

more positive evidence for the psychological effects of massage.

sportEX dynamics 2010;24(Apr):4-6