The purpose of this study was to investigate the specificity of the effects of massage (petrissage) on spinal motoneuron excitability as measured by changes in the peak-to-peak amplitude of H-reflex recordings. H-reflexes (and M-responses) were recorded from the distal aspects of the right triceps surae muscle of 8 men and 8 women, aged 20 to 37 years, with no neuromuscular impairments of the lower extremities. The H-reflexes were recorded during five control and four experimental conditions (20 trials at each condition). The control conditions (C1-C5) preceded and followed each experimental condition, providing a measure of the stability of the H-reflex. Each experimental condition consisted of a 4-minute period of massage of the ipsilateral and contralateral triceps surae and hamstring muscle groups (ITS, CTS, IHS, and CHS, respectively). The mean peak-to-peak amplitude of the H-reflex was found to be stable (range = 1.91-1.95 mV) across the five control conditions. H-reflex amplitudes recorded during the experimental conditions indicate that massage of the ITS resulted in a reduction of the H-reflex (0.83 mV) in comparison with the pretest control condition (C1) and the remaining experimental conditions (range = 1.77-2.23 mV). This difference was significant, and subsequent Newman-Keuls tests indicated a specificity of the effects of massage on the muscle group being massaged. [Sullivan SJ, Williams LRT, Seaborne DE, Morelli M. Effects of massage on alpha motoneuron excitability.
Reaction time (RT), movement time (MT), total response time (RMT), and accuracy of 3 elite and 3 novice fencers were studied under a dual response paradigm requiring a full lunge. Electromyographic activity (EMG) from selected arm and leg muscles was used to compare response profiles of the two groups. Although the elite subjects had slower MTs, their faster RTs resulted in significantly shorter total response times. The EMG analysis showed that in comparison to the novice subjects, onset of muscle activity was significantly faster for the elite group in five of the six muscles studied. In addition, the elite subjects showed more coherent muscle synergies and more consistent patterns of muscle coordination. Although the requirement to change targets (signalled by the arrival of a second stimulus) led to slightly more target misses for the elite group, the overall frequency was low, which indicates that it did not pose difficulty for either group. The present findings show that measures of response timing and neuromuscular coordination differentiate skill level in the fencing lunge and draw attention to practical implications for skill assessment and training.
The purpose of this study was to ascertain coping styles among competitive athletes in response to various acute stressors. Specifically, the authors used a 134-item survey to measure approach and avoidance coping styles, with task-focused and emotion-focused coping tendencies nested hierarchically as subdimensions under each. Australian and U.S. college-aged participants indicated the extent to which they used approach, avoidance, task-focused, and emotion-focused coping strategies (a 4-factor model) in response to selected acute stressors experienced during sport competition. The authors computed confirmatory factor analysis to test the theoretically driven model. The criterion loading of .30 and above for each of the factors reduced the survey to 65 items. Findings indicated stronger links between the 2 approach constructs of task- and emotion-focused coping than between the 2 avoidance constructs of those subdimensions. The goodness-of-fit indices for the 4-factor model were 0.58 and 0.57 for Australian and U.S. samples, respectively, and .71 overall. Concomitant low correlations between the 2 approach (0.18) and the 2 avoidance dimensions (0.43) reflected relatively high residuals between stressors. In general, psychometric analyses suggest that coping style may be more prevalent in some situations than others, lending partial support for the transactional model of coping.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.