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Background: Patients with rheumatoid arthritis (RA) have an increased risk for cardiovascular disease (CVD) with poor parasympathetic function being implicated as an underlying factor. Factors related to parasympathetic function, commonly assessed by heart rate recovery (HRR) following maximal exercise, are currently not known in RA. We aimed to explore the association between HRR with CVD risk factors, inflammatory markers, and wellbeing in patients with RA. Methods: Ninety-six RA patients (54.4 ± 12.6 years, 68 % women) completed a treadmill exercise test, during which heart rate (HR) was monitored. HRR1 and HRR2 were defined as the absolute change from HR peak to HRR 1 min post HR peak and 2 min post HR peak, respectively. Cardiorespiratory fitness, CVD risk factors, and serological markers of inflammation were measured in all patients. The Framingham Risk Score (FRS) was used as an assessment of global risk for CVD events, and wellbeing was assessed by questionnaires. Results: Mean HRR1 and HRR2 were 29.1 ± 13.2 bpm and 46.4 ± 15.3 bpm, respectively. CVD risk factors as well as most inflammatory markers and measures of wellbeing were inversely correlated with HRR1 and HRR2. Multivariate regression analyses revealed that 27.9 % of the variance in HRR1 and 37.9 % of the variance in HRR2 was explained collectively by CVD risk factors, measures of inflammation, and wellbeing (p = 0.009, p = 0.001 respectively), however no individual measure was independently associated with HRR1 or HRR2. Conclusion: Parasympathetic activation was associated with overall CVD risk, arthritis-related burden and wellbeing in patients with RA. Trial Registration: [Exercise, cardiovascular disease and rheumatoid arthritis, ISRCTN04121489 ]

Background Patients with Rheumatoid Arthritis (RA) can participate in regular physical activity (PA) without disease aggravation and accrue health benefits, including enhanced physical and psychological health [1]. However, Self-determination Theory [2] proposes that the reasons why we participate in PA may determine the extent to which beneficial outcomes from PA can be accrued. Specifically, the benefits associated with PA participation will be maximised when one participates for autonomous reasons (i.e., enjoyment or personally valuing the benefits of PA) rather than for controlled reasons (i.e., because a health professional has told you to) [3]. Objectives To test whether reasons for participating in PA (motivation) explains variability in reported physical function and psychological health (subjective vitality and depressive symptoms) in addition to that of self-reported moderate to vigorous physical activity (MVPA). Methods One hundred and six RA patients (Mage 54.5±12.3 years, 68% female, BMI = 28.10±5.80 kg/m2) completed the following questionnaires before entering a PA intervention: International Physical Activity Questionnaire, Subjective Vitality Scale, Behavioural Regulation in Exercise Questionnaire-2, Hospital Anxiety and Depression Scales and Health Assessment Questionnaire. Multiple hierarchical regression analyses were conducted controlling for disease activity (C-reactive protein). MVPA was added in Step 1 of the regression and motivation added in Step 2. Results Analyses revealed that MVPA (b=0.29; p=0.04) significantly predicted subjective vitality [F(2,93)=4.37; p=0.02], explaining 9% of the variance. When motivation for participating in PA (b=0.27; p=0.006) was added, the model remained significant [F(3,92)=5.5; p=0.002] and explained an additional 7% of the variance. MVPA did not predict depressive symptoms [F(2,99)=2.8; p=0.07] but motivation was significantly and negatively related to reported depression [b= -0.30; p=0.01; F(3,98)=5.54; p=0.001], explaining 9% of the variance. MVPA did not significantly predict physical function [F(2,94)=1.65; p=0.20] but motivation was significant [b=0.2.60; p=0.009;] and explained 7% of the variance. Conclusions More autonomous motivations for participating in PA were associated with a range of improvements in both physical and psychological health outcomes. Future PA promotion interventions in RA patients could maximise treatment benefits, such as improvements in physical function and feelings of vitality as well as reductions in depressive symptoms. This could be achieved by increasing enjoyment of PA and awareness of the benefits associated with this important health behaviour.

No prior research has examined how motivation for goal striving influences persistence in the face of increasing goal difficulty. This research examined the role of self-reported (Study 1) and primed (Study 2) autonomous and controlled motives in predicting objectively assessed persistence during the pursuit of an increasingly difficult goal. In Study 1, 100 British athletes (64 males; Mage?=?19.89 years, SDage?=?2.43) pursued a goal of increasing difficulty on a cycle ergometer. In Study 2, 90 British athletes (43 males; Mage?=?19.63 years, SDage?=?1.14) engaged in the same task, but their motivation was primed by asking them to observe a video of an actor describing her or his involvement in an unrelated study. In Study 1, self-reported autonomous goal motives predicted goal persistence via challenge appraisals and task-based coping. In contrast, controlled goal motives predicted threat appraisals and disengagement coping, which, in turn, was a negative predictor of persistence. In Study 2, primed autonomous (compared to controlled) goal motives predicted greater persistence, positive affect, and future interest for task engagement. The findings underscore the importance of autonomous motivation for behavioral investment in the face of increased goal difficulty.

Background Rheumatoid arthritis (RA) is the most prevalent chronic inflammatory arthritis characterized by periods of remission and flares in disease activity unique to each individual. Consequently, patients with RA experience fluctuations in both physical and psychological health and well-being (1). Subjective vitality is an indicator of positive health/optimal functioning and has been conceptualised as a sense of being alive and full of energy. Therefore, if the Subjective Vitality Scale (2) demonstrates convergent validity with indicators of physical and psychological health in RA patients, it could provide a brief and clinically relevant assessment tool. Objectives To investigate the associations between subjective vitality and indicators of physical health (i.e. physical function and cardio-respiratory fitness), and psychological health (i.e. quality of life, fatigue, depression and anxiety) amongst RA patients. Methods Patients with RA (N=106, age 54.5±12.3 years, 68% women) completed a questionnaire pack and an exercise tolerance test to assess cardio-respiratory fitness (VO2max).The Subjective Vitality Scale contains five items (e.g. “I feel alive and full of vitality”). Participants responded to how much vitality, over the last two weeks, they felt, using a scale anchored by 1 (not at all true) and 7 (very true). Participants were also asked to complete the following measures: Multidimensional Assessment of Fatigue to measure physical function, (3) Hospital Anxiety and Depression Scales, (4) Health Assessment Questionnaire to measure physical function (5) and the EuroQol (6). A blood sample was provided to measure C-reactive protein, an indicator of disease activity. Results Partial correlations were conducted controlling for age, gender and disease activity.

The capillary-column inverse gas chromatography method was used to measure the diffusion and partition coefficients of ethylbenzene, styrene, and acrylonitrile in polybutadiene (PBD) at infinite dilution of the solvents. Experiments were performed over a temperature range of 50-125 °C. At temperatures well above the glass-transition temperature of PBD, the diffusivities were correlated using an Arrhenius expression. The Arrhenius parameters in turn were intercorrelated and shown to be a function of the occupied volume, thus providing a method for predicting the diffusion of other solvents in the same polymer. Further, the activation energy was predicted using the Duda-Vrentas free-volume approach. The activation energy thus obtained was compared with the activation energy of the Arrhenius approach. The weight-fraction activity coefficient data were compared to the predictions of the group contribution, lattice-fluid equation-of-state, and the UNIquac Functional-group Activity Coefficient (UNIFAC) free-volume models.