Eccentric exercise induces spatial changes in the mechanomyographic activity of the upper trapezius muscle.

In this study, we hypothesized that the recordings of multichannel mechanomyography (MMG) of the upper trapezius muscle would reveal spatially dependent manifestations in the presence of delayed onset muscle soreness occurring 24 hours after eccentric exercise (ECC). Sixteen participants performed high-intensity eccentric exercises (5 sets of 10 eccentric contractions at 100% of max elevation force) targeting the upper trapezius on their dominant side. Twelve accelerometers were attached to record MMG activity during submaximal exercise consisting of static and dynamic arm flexion and abduction. Measurements were taken before and 24 hours after ECC. Average rectified value (ARV), percentage of determinism (% DET), and recurrence (% REC) of the MMG signals were computed to estimate the level of muscular activity and the magnitude of regularity of the MMG. The ARV, % REC, and % DET maps revealed heterogeneous MMG activity of the upper trapezius 24 hours after ECC when compared with before. Increased ARV, % REC, and % DET were found 24 hours after ECC when compared with before. The study provides new key information on how a single muscle responds to ECC. Our findings suggest that multichannel MMG and nonlinear analyses may detect muscular and musculo-tendinous alterations due to ECC.

Effects of two recovery procedures after a football game on sensory and biochemical markers.

AIM: The aim of this study was to investigate recovery processes on pressure pain sensitivity and blood indicators in professional football players after three different post-game training modalities: standard recovery training, no physical activity, delayed onset muscle soreness reduction training. METHODS: Eleven male football field players participated in the present study. The experiment was performed in three sessions over three weeks after three football league games. The procedure was composed of the following assessments included in each session: measurement of pain pressure threshold, creatine kinase activity and myoglobin (Mb) concentration before, 24 and 48 hours after game. RESULTS: In standard recovery training there was no full recovery in deep structure sensitivity of the frontal thigh muscles at 48 hours after game (P=0.008). In the no physical activity session, sensitivity returned to its level before game. On the contrary, in the delayed onset muscle soreness reduction training sensitivity decreased 48 hours after game (P<0.001). Creatine kinase activity decreased significantly from 24 hours to 48 hours in session with no activity and delayed onset muscle soreness reduction training (P<0.05). None of the recovery methods had an influence on Mb concentration. CONCLUSION: The present study points towards a potent effect of delayed onset muscle soreness reduction training on recovery after a football game.

Personality and the incidence of hypertension among older men: longitudinal findings from the Normative Aging Study.

Personality predictors of hypertension incidence were studied in 838 community-residing men from the Normative Aging Study. They were followed over a mean of 17 years during which time 38% developed hypertension. Stepwise proportional hazards regression was used to identify scales from the Cattell 16 Personality Factor Questionnaire that predicted hypertension incidence, controlling for biomedical, social, and behavioral risk factors. There was a significant negative relation between the personality trait of emotional stability and the incidence of hypertension, controlling for baseline blood pressure, education, and alcohol consumption. These results support those who argue that personality characteristics predict the development of hypertension.

Construct validation of optimism and pessimism in older men: findings from the normative aging study.

Validation of Scheier and Carver's (1985) Life Orientation Test (LOT) has identified associations between bipolar optimism and several external constructs. However, optimism and pessimism may be not bipolar, but rather separate constructs. Furthermore, these constructs may be indistinguishable from personality traits, such as neuroticism and extraversion. This study examined the associations of separate optimism and pessimism measures with self-reports of hassles, psychological symptoms, and illness severity, controlling for personality. Ss were 1,192 men from the Normative Aging Study. Findings suggest that optimism and pessimism are separate and that their relations to external criteria remain, although attenuated, when neuroticism and extraversion are controlled.

The effect of age on positive and negative affect: a developmental perspective on happiness.

The effect of age on happiness, as defined by positive and negative affect, was examined in a survey of 2,727 persons of a broad age range (25-74) conducted by the MacArthur Foundation Research Network on Successful Midlife Development. The age-affect association was examined, controlling for a host of sociodemographic, personality, and contextual influences. Among women, age was related to positive affect nonlinearly but was unrelated to negative affect. Among men, age interacted with 2 key variables in predicting affect: extraversion and marital status. These findings lend support to recent life span theories of emotion and indicate that personality, contextual, and sociodemographic variables, as well as their interactions, are all needed to fully understand the age-affect relationship.

Some methodological issues in the development of quality of life measures for the evaluation of medical interventions.

This paper discusses a series of important methodological issues in developing targeted health-related quality of life measures in studies of the effects of medical interventions. Such measures cannot be developed unless the evaluator understands the life domains that medical interventions affect. Qualitative discovery methods are needed to obtain this understanding. Once domains are targeted for measurement, careful and systematic laboratory pilot work should be used to select initial scale items. Psychometric evaluation of response patterns in subsequent field tests is needed to assess the measures. Less concern should be directed to internal consistency reliability of scales in the psychometric evaluation and more to the ability of short scales to reproduce total scale variance and to provide precise measurement within the range of the outcome where effects are expected. The paper closes with a discussion of modern methods of item response scaling that can be used to address these issues.

Evaluating a measure of the five-factor model of personality.

An evaluation is made of Goldberg s (1992) 100 Unipolar Markers of the five-factor model of personality. The factor structure of these items in samples of older men from the Normative Aging Study and undergraduate students are examined, and both item transformation and consistency testing approaches are used to evaluate replications of the five-factor structure. Results show that the five-factor structure is difficult to replicate in the sample of older men. While item transformations and sample trimming based on a consistency test did improve the quality of the replication in this older, nonstudent sample, both methods have serious drawbacks. The five-factor solution appeared in the student sample without sample trimming or data transformation. Additionally, in both student and nonstudent samples, oblique rotation resulted in inter-factor correlations relevant to more general issues in the study of trait structure. We conclude that the 100 Unipolar Markers may be unsuitable for use in older populations or with nonstudent samples.

The effects of the Columbia shuttle disaster on the daily lives of older adults: findings from the VA Normative Aging Study.

During 2002-2003 the VA Normative Aging Study conducted an eight-day diary survey of stressors and well-being. A sub-sample of 19 men and 13 women (mean age = 71.78) completed daily questionnaires before and after the Columbia shuttle exploded on 1st February 2003, presenting a unique look into peoples' daily lives before and after a tragic event. Results indicated no significant changes in negative affect or physical symptoms, but people reported significant decreases in both positive affect and memory failures on days following the shuttle explosion. Implications of these findings and directions for future research are discussed.

Measuring the effects of medical interventions.

This article reviews a number of important issues in selecting health-related quality-of-life measures in studies of the effects of medical interventions. Concerning the selection of domains, a plea is made for a greater use of qualitative discovery methods than is currently the case. It is also argued that measures of specific outcomes are inadequate to describe fully the effects of medical interventions, and must be coupled with more general outcome measures. Concerning the selection of measures, an argument is made that psychometric evaluation should be less concerned with the internal consistency reliability of short outcome measures and more with the ability of short-form measures to reproduce total scale variance. It is also noted that precision of measurement has been a neglected topic in the psychometric evaluation of outcome measures in this area of research. Future work should consider precision within the range of the outcome where effects are expected much more seriously. Finally, future methodologic work is called for using methods based on item response theory to study precision and bias.

The neglect of response bias in mental health research.

A number of researchers have observed that response biases, defined as when subjects respond to items in research instruments in ways that do not coincide with the intent or content of the instrument, suffuse measurements and assessments of mental disorders. They cautioned that the response bias problem has been neglected in mental health research at the price of substantial error. Have the cautions been heeded? Or does the neglect of response bias continue? Articles published in 1998 in three major psychiatric journals were examined: Archives of General Psychiatry, American Journal of Psychiatry, and the Journal of Nervous and Mental Disease. The articles were examined to determine whether response biases were mentioned and whether systematic efforts were made to attend to their influence on the findings of the study. Each article was assessed twice by independent raters. The examination indicates that a very small minority of the articles reviewed mentioned response bias and that among those mentioning it, a minority attempted to control for bias effects. Cautions offered about response bias have not been heeded. Accordingly, the issue is one of how to incorporate concerns about response bias into the institutional structures that influence the culture of mental health research.