Regular exercise participation mediates the affective response to acute bouts of vigorous exercise.

Physical inactivity is a leading factor associated with cardiovascular disease and a major contributor to the global burden of disease in developed countries. Subjective mood states associated with acute exercise are likely to influence future exercise adherence and warrant further investigation. The present study examined the effects of a single bout of vigorous exercise on mood and anxiety between individuals with substantially different exercise participation histories. Mood and anxiety were assessed one day before an exercise test (baseline), 5 minutes before (pre-test) and again 10 and 25 minutes post-exercise. Participants were 31 university students (16 males, 15 females; Age M = 20), with 16 participants reporting a history of regular exercise with the remaining 15 reporting to not exercise regularly. Each participant completed an incremental exercise test on a Monark cycle ergometer to volitional exhaustion. Regular exercisers reported significant post-exercise improvements in mood and reductions in state anxiety. By contrast, non-regular exercisers reported an initial decline in post-exercise mood and increased anxiety, followed by an improvement in mood and reduction in anxiety back to pre-exercise levels. Our findings suggest that previous exercise participation mediates affective responses to acute bouts of vigorous exercise. We suggest that to maximise positive mood changes following exercise, practitioners should carefully consider the individual's exercise participation history before prescribing new regimes. Key pointsPrevious exercise participation mediates the affective response to acute bouts of vigorous exercise.Regular exercisers respond positively to acute bouts of vigorous physical activity, reporting less state anxiety and fatigue, and more vigour.Non-regular exercisers respond with an initial reduction in positive mood states, followed by a rebound to baseline levels 25 minutes post-exercise.To maximise positive post-exercise mood states, especially among novice exercisers, practitioners should carefully consider previous exercise participation when prescribing new exercise regimes.

The impact of patient self assessment of deformity on HRQL in adults with scoliosis.

BACKGROUND: Body image and HRQL are significant issues for patients with scoliosis due to cosmetic deformity, physical and psychological symptoms, and treatment factors. A selective review of scoliosis literature revealed that self report measures of body image and HRQL share unreliable correlations with radiographic measures and clinician recommendations for surgery. However, current body image and HRQL measures do not indicate which aspects of scoliosis deformity are the most distressing for patients. The WRVAS is an instrument designed to evaluate patient self assessment of deformity, and may show some promise in identifying aspects of deformity most troubling to patients. Previous research on adolescents with scoliosis supports the use of the WRVAS as a clinical tool, as the instrument shares strong correlations with radiographic measures and quality of life instruments. There has been limited use of this instrument on adult populations. METHODS: The WRVAS and the SF-36v2, a HRQL measure, were administered to 71 adults with scoliosis, along with a form to report age and gender. Preliminary validation analyses were performed on the WRVAS (floor and ceiling effects, internal consistency and collinearity, correlations with the SF-36v2, and multiple regression with the WRVAS total score as the predictor, and SF-36v2 scores as outcomes). RESULTS: The psychometric properties of the WRVAS were acceptable. Older participants perceived their deformities as more severe than younger participants. More severe deformities were associated with lower scores on the Physical Component Summary Score of the SF-36v2. Total WRVAS score also predicted Physical Component Summary scores. CONCLUSION: The results of the current study indicate that the WRVAS is a reliable tool to use with adult patients, and that patient self assessment of deformity shared a relationship with physical rather than psychological aspects of HRQL. The current and previous studies concur that revision of the WRVAS is necessary to more accurately represent the diversity of scoliosis deformities. Ability to identify disturbing aspects of deformity could potentially be improved by evaluating each WRVAS items against indicators of pain, physical/psychosocial function, and self image from previous measures such as the SRS, SF-36 or BSSQ-deformity.

Paradoxical effects of hedonic disparities in negative anticipatory contrast.

Negative anticipatory contrast (NAC) occurs when the presentation of two solutions in sequence over a number of trials leads to the suppression in consumption of the first solution. A hedonic 'disparity' between the two solutions may lead to this suppression. However, what the relative role of the gustatory properties versus the nutricaloric loads of the two solutions is in determining the acquisition of NAC is uncertain. Previous experiments have typically used saccharine and sucrose solutions, which resemble each other in gustatory properties yet differ in their nutricaloric loads. In contrast, the present experiments used soy milk and sucrose solutions, which are both highly nutritive but differ in their gustatory properties. Soy milk was found to have a higher hedonic value than a 16% sucrose solution as measured by both choice and absolute consumption. According to a hedonic disparity hypothesis, NAC should have occurred using a sucrose-soy sequence but not a soy-sucrose sequence. Paradoxically, the sucrose-soy sequence failed to yield NAC, but the soy-sucrose sequence did yield a repeatable, significant NAC. A consideration of the available theory and research indicated that NAC may be explained by a strong conditioning of a satiety response produced by sucrose that opposes the conditioning of sucrose's positive hedonic response.

In vivo behavior of a Helicobacter pylori SS1 nixA mutant with reduced urease activity.

Helicobacter pylori mutants devoid of urease activity fail to colonize the gastric mucosa of mice; however, the effect of decreased levels of urease on colonization has not been examined. The nixA gene, required for full urease activity, encodes a cytoplasmic membrane nickel transporter that imports nickel ions and leads to incorporation of nickel ions into apourease. A nixA mutant of the Sydney strain of H. pylori (SS1) was constructed by disruption of the nixA gene with a kanamycin resistance cassette. This mutant retained only half the urease activity of the wild-type (wild-type) SS1 strain. C57BL/6j (n = 75) and BALB/c (n = 75) mice were inoculated independently with the wild-type or the nixA strain. The level and distribution of colonization were assessed by bacterial colony counts and histological grading at 4, 12, and 24 weeks postinfection. Colonization levels of the nixA strain in BALB/c mice were significantly lower compared with SS1 (P = 0.005), while colonization in C57BL/6j mice was similar for both the wild-type and mutant strains. Subtle differences in colonization of the different regions of the stomach, determined by microscopic grading, were observed between wild-type SS1 and the nixA strain in BALB/c mice. On the contrary, when C57BL/6j (n = 35) and BALB/c (n = 35) mice were coinfected with the wild-type and nixA strains simultaneously, the nixA mutant failed to colonize and was outcompeted by the wild-type SS1 strain, which established normal levels of colonization. These results demonstrate the importance of the nixA gene for increasing the fitness of H. pylori for gastric colonization. Since nixA is required for full urease activity, the decreased fitness of the nixA mutant is likely due to reduced urease activity; however, pleiotropic effects of the mutation cannot be completely ruled out.