Heather Tulloch

Determinants of physical activity after hospitalization for coronary artery disease: the Tracking Exercise After Cardiac Hospitalization (TEACH) Study

Background Little is known about physical activity levels in patients with coronary artery disease (CAD) who are not engaged in cardiac rehabilitation. We explored the trajectory of physical activity after hospitalization for CAD, and examined the effects of demographic, medical, and activity-related factors on the trajectory. Design A prospective cohort study. Methods A total of 782 patients were recruited during CAD-related hospitalization. Leisure-time activity energy expenditure (AEE) was measured 2, 6 and 12 months later. Sex, age, education, reason for hospitalization, congestive heart failure (CHF), diabetes, and physical activity before hospitalization were assessed at recruitment. Participation in cardiac rehabilitation was measured at follow-up. Results AEE was 1948 ± 1450, 1676 ± 1290, and 1637 ± 1486 kcal/week at 2, 6 and 12 months, respectively. There was a negative effect of time from 2 months post-hospitalization on physical activity (P<0.001). Interactions were found between age and time (P = 0.012) and education and time (P = 0.001). Main effects were noted for sex (men more active than women; P<0.001), CHF (those without CHF more active; P<0.01), diabetes (those without diabetes more active; P<0.05), and previous level of physical activity (those active before hospitalization more active after; P<0.001). Coronary artery bypass graft patients were more active than percutaneous coronary intervention (PCI) patients (P = 0.033). Conclusions Physical activity levels declined from 2 months after hospitalization. Specific subgroups (e.g. less educated, younger) were at greater risk of decline and other subgroups (e.g. women, and PCI, CHF, and diabetic patients) demonstrated lower physical activity. These groups need tailored interventions.

Effect of Exercise Training on Physical Fitness in Type II Diabetes Mellitus

UNLABELLED Few studies have compared changes in cardiorespiratory fitness between aerobic training only or in combination with resistance training. In addition, no study to date has compared strength gains between resistance training and combined exercise training in type II diabetes mellitus (T2DM). PURPOSE We evaluated the effects of aerobic exercise training (A group), resistance exercise training (R group), combined aerobic and resistance training (A + R group), and sedentary lifestyle (C group) on cardiorespiratory fitness and muscular strength in individuals with T2DM. METHODS Two hundred and fifty-one participants in the Diabetes Aerobic and Resistance Exercise trial were randomly allocated to A, R, A + R, or C. Peak oxygen consumption (V O(2peak)), workload, and treadmill time were determined after maximal exercise testing at 0 and 6 months. Muscular strength was measured as the eight-repetition maximum on the leg press, bench press, and seated row. Responses were compared between younger (aged 39-54 yr) and older (aged 55-70 yr) adults and between sexes. RESULTS VO(2peak) improved by 1.73 and 1.93 mL O(2)*kg(-1)*min(-1) with A and A + R, respectively, compared with C (P < 0.05). Strength improvements were significant after A + R and R on the leg press (A + R: 48%, R: 65%), bench press (A + R: 38%, R: 57%), and seated row (A + R: 33%, R: 41%; P < 0.05). There was no main effect of age or sex on training performance outcomes. There was, however, a tendency for older participants to increase VO(2peak) more with A + R (+1.5 mL O(2)*kg(-1)*min(-1)) than with A only (+0.7 mL O(2)*kg(-1)*min(-1)). CONCLUSIONS Combined training did not provide additional benefits nor did it mitigate improvements in fitness in younger subjects compared with aerobic and resistance training alone. In older subjects, there was a trend to greater aerobic fitness gains with A + R versus A alone.

Effects of Aerobic Training, Resistance Training, or Both on Percentage Body Fat and Cardiometabolic Risk Markers in Obese Adolescents: The Healthy Eating Aerobic and Resistance Training in Youth Randomized Clinical Trial

IMPORTANCE Little evidence exists on which exercise modality is optimal for obese adolescents. OBJECTIVE To determine the effects of aerobic training, resistance training, and combined training on percentage body fat in overweight and obese adolescents. DESIGN, SETTING, AND PARTICIPANTS Randomized, parallel-group clinical trial at community-based exercise facilities in Ottawa (Ontario) and Gatineau (Quebec), Canada, among previously inactive postpubertal adolescents aged 14 to 18 years (Tanner stage IV or V) with body mass index at or above the 95th percentile for age and sex or at or above the 85th percentile plus an additional diabetes mellitus or cardiovascular risk factor. INTERVENTIONS After a 4-week run-in period, 304 participants were randomized to the following 4 groups for 22 weeks: aerobic training (n = 75), resistance training (n = 78), combined aerobic and resistance training (n = 75), or nonexercising control (n = 76). All participants received dietary counseling, with a daily energy deficit of 250 kcal. MAIN OUTCOMES AND MEASURES The primary outcome was percentage body fat measured by magnetic resonance imaging at baseline and 6 months. We hypothesized that aerobic training and resistance training would each yield greater decreases than the control and that combined training would cause greater decreases than aerobic or resistance training alone. RESULTS Decreases in percentage body fat were -0.3 (95% CI, -0.9 to 0.3) in the control group, -1.1 (95% CI, -1.7 to -0.5) in the aerobic training group (P = .06 vs controls), and -1.6 (95% CI, -2.2 to -1.0) in the resistance training group (P = .002 vs controls). The -1.4 (95% CI, -2.0 to -0.8) decrease in the combined training group did not differ significantly from that in the aerobic or resistance training group. Waist circumference changes were -0.2 (95% CI, -1.7 to 1.2) cm in the control group, -3.0 (95% CI, -4.4 to -1.6) cm in the aerobic group (P = .006 vs controls), -2.2 (95% CI -3.7 to -0.8) cm in the resistance training group (P = .048 vs controls), and -4.1 (95% CI, -5.5 to -2.7) cm in the combined training group. In per-protocol analyses (≥ 70% adherence), the combined training group had greater changes in percentage body fat (-2.4, 95% CI, -3.2 to -1.6) vs the aerobic group (-1.2; 95% CI, -2.0 to -0.5; P = .04 vs the combined group) but not the resistance group (-1.6; 95% CI, -2.5 to -0.8). CONCLUSIONS AND RELEVANCE Aerobic, resistance, and combined training reduced total body fat and waist circumference in obese adolescents. In more adherent participants, combined training may cause greater decreases than aerobic or resistance training alone. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00195858.

Randomized trial of an internet-based computer-tailored expert system for physical activity in patients with heart disease

Background: The CardioFit internet-based expert system was designed to promote physical activity in patients with coronary heart disease (CHD) who were not participating in cardiac rehabilitation. Design: This randomized controlled trial compared CardioFit to usual care to assess its effects on physical activity following hospitalization for acute coronary syndromes. Methods: A total of 223 participants were recruited at the University of Ottawa Heart Institute or London Health Sciences Centre and randomly assigned to either CardioFit (n = 115) or usual care (n = 108). The CardioFit group received a personally tailored physical-activity plan upon discharge from the hospital and access to a secure website for activity planning and tracking. They completed five online tutorials over a 6-month period and were in email contact with an exercise specialist. Usual care consisted of physical activity guidance from an attending cardiologist. Physical activity was measured by pedometer and self-reported over a 7-day period, 6 and 12 months after randomization. Results: The CardioFit internet-based physical activity expert system significantly increased objectively measured (p = 0.023) and self-reported physical activity (p = 0.047) compared to usual care. Emotional (p = 0.038) and physical (p = 0.031) dimensions of heart disease health-related quality of life were also higher with CardioFit compared to usual care. Conclusions: Patients with CHD using an internet-based activity prescription with online coaching were more physically active at follow up than those receiving usual care. Use of the CardioFit program could extend the reach of rehabilitation and secondary-prevention services.

Understanding physical activity in adults with type 2 diabetes after completing an exercise intervention trial: A mediation model of self-efficacy and autonomous motivation

This study was set out to test if autonomous motivation mediated the relationship between self-efficacy and 12-month physical activity (PA) in adults with type 2 diabetes involved in a randomized exercise trial. Participants (n = 234) completed questionnaires measuring barrier self-efficacy at 3 months, autonomous motivation at 6 months, and PA at 12 months. A mediational analysis of longitudinal data revealed that autonomous motivation mediated the relationship between barrier-self-efficacy and PA. High barrier self-efficacy can therefore help predict 12-month PA in adults with type 2 diabetes, although this effect is attenuated by autonomous motivation. Hence, participating in PA for autonomous reasons such as by choice and/or for fun further explains PA at 12 months in this population. Results of this study extend our understanding of the motivational constructs involved in PA in the maintenance phase. This study has important theoretical implications in that it helps to organize and consolidate well-known correlates of PA by proposing a temporal relationship between them that could be tailored in interventions.

Predicting short and long-term exercise intentions and behaviour in patients with coronary artery disease: A test of protection motivation theory

The purpose of this study was to examine the utility of protection motivation theory (PMT) in the prediction of exercise intentions and behaviour in the year following hospitalisation for coronary artery disease (CAD). Patients with documented CAD (n = 787), recruited at hospital discharge, completed questionnaires measuring PMTs threat (i.e. perceived severity and vulnerability) and coping (i.e. self-efficacy, response efficacy) appraisal constructs at baseline, 2 and 6 months, and exercise behaviour at baseline, 6 and 12 months post-hospitalisation. Structural equation modelling showed that the PMT model of exercise at 6 months had a good fit with the empirical data. Self-efficacy, response efficacy, and perceived severity predicted exercise intentions, which, in turn predicted exercise behaviour. Overall, the PMT variables accounted for a moderate amount of variance in exercise intentions (23%) and behaviour (20%). In contrast, the PMT model was not reliable for predicting exercise behaviour at 12 months post-hospitalisation. The data provided support for PMT applied to short-term, but not long-term, exercise behaviour among patients with CAD. Health education should concentrate on providing positive coping messages to enhance patients’ confidence regarding exercise and their belief that exercise provides health benefits, as well as realistic information about disease severity.

The MacNew Heart Disease Health-Related Quality of Life Questionnaire in Patients with Angina and Patients with Ischemic Heart Failure

OBJECTIVE Patient-reported outcomes including health-related quality of life are important in clinical care and research studies. The MacNew Heart Disease Health-Related Quality Of Life Questionnaire has been validated in English-speaking patients with myocardial infarction. The aim of this study was to validate the MacNew in English-speaking patients with angina or ischemic heart failure. METHODS Canadian and American patients with angina or ischemic heart failure completed the MacNew, the Short Form-36 Health Survey, and the Hospital Anxiety and Depression Scale. RESULTS We administered questionnaires to 276 patients with angina (mean age, 65.9 years) and 155 patients with ischemic heart failure (mean age, 70.3 years). The mean ± SD MacNew global score in patients with ischemic heart failure (5.1 ± 1.2) was statistically (P < 0.001), but not clinically, poorer than in patients with angina (5.3 ± 1.1). The three-factor measurement model explained 46.1% of the observed variance in the MacNew in patients with angina and 46.5% in patients with ischemic heart failure. Internal consistency was ≥0.90, and test-retest reliability was ≥0.70 for each MacNew scale and the a priori convergent and discriminative validity hypotheses were confirmed in both diagnoses. The MacNew was highly accepted by patients with little respondent or administrative burden. CONCLUSIONS The English version of the MacNew is reliable and valid in patients with angina or ischemic heart failure. This permits health-related quality of life outcome comparisons in patients with angina, ischemic heart failure, and myocardial infarction with the MacNew and provides a better understanding of the full range of health-related quality of life outcomes.

Self-determination and Exercise Stages of Change: Results from the Diabetes Aerobic and Resistance Exercise Trial

Little longitudinal research exists on the relationship between exercise self-determination and stage of change. This study investigated how self-determined motivation changes in patients with type 2 diabetes (N = 175) as they moved through the stages of change over a six-month exercise trial. Hierarchical linear modelling revealed that patients who progressed through the stages of exercise change had an overall increase in self-determined motivation, while non-progressors experienced a reduction in self-determined motivation from three to six months. These results indicate that individuals engaging in regular exercise at six months maintain initial increases in self-determined motivation. Findings are discussed in light of self-determination theory.

RESEARCH: "Religious Framing by Individuals With PTSD When Writing About Traumatic Experiences"

Writing about traumatic events can produce physical and psychological health benefits, especially when individuals use language to transform emotionally laden events into meaningful narratives. Because religion often facilitates the search for meaning, we predicted that the use of religious themes in writing would moderate mood-related outcomes. Fifteen individuals with posttraumatic stress disorder (PTSD) wrote in each of 3 sessions about their PTSD-triggering events. Religious themes were evident in essays written by 80 percent of participants. Relative to participants who did not frame their traumas in religious terms, those who used religious framing reported a greater shift toward negative mood after the first writing session than those without such framing. By the third session, however, religious framing was associated with more positive mood after writing, whereas nonreligious framing was still associated with more negative mood. The nature of religious references was important. Positive references and specific religious behaviors (e.g., prayer) were associated with more positive mood states, whereas negative religious references were not associated with mood. Implications for research and practice are discussed.

Patterns of Motivation and Ongoing Exercise Activity in Cardiac Rehabilitation Settings: A 24-Month Exploration from the TEACH Study

BackgroundFew studies have explored exercise and motivational patterns of cardiac rehabilitation patients in the long term.PurposeWe explored differential patterns of exercise and motivation in cardiac rehabilitation patients over a 24-month period and examined the relationship between these emerging patterns.MethodsParticipants (n = 251) completed an exercise, barrier self-efficacy, outcome expectations and self-determined motivation questionnaire. Latent class growth modelling was used to classify patients in different exercise and motivational patterns.ResultsThree exercise patterns emerged: inactive, non-maintainers and maintainers (16%, 67% and 17% of sample per pattern, respectively). Multiple trajectories were found for barrier self-efficacy, outcome expectations and self-determined motivation (3, 5, and 4, respectively). Patients in high barrier self-efficacy, outcome expectation and self-determined groups had greater probability of being in the maintainer exercise group.ConclusionsIdentifying a patient’s exercise and motivational profile could help cardiac rehabilitation programmes tailor their intervention to optimize the potential for continued exercise activity.