Changes In Cardiovascular Fitness Research Articles

Randomised control trial of a novel digital system to provide contextualised data feedback to augment physical activity behaviour change in a free-living environment as part of cardiac rehabilitation

Abstract Background Physical activity (PA) is a core component of cardiac rehabilitation (CR) and is crucial for enhancing cardiovascular (CV) fitness[1]. In the UK, CR programmes involve 1-2 hours of face-to-face contact per week over 6-8 weeks, implying that 98-99% of the intervention period is currently unmonitored and not optimised for potential positive lifestyle interventions. Consequently, CR staff are blind to PA that occurs outside of the clinical setting, which could be of too low or high intensity and/or duration, according to the Association of Certified Physiotherapists in Cardiac Rehabilitation (ACPICR) guidelines[2]. A previous pilot study showed a novel digital system to be feasible, acceptable and effective for CR patients[3], making it a promising intervention to assess in a randomised control trial (RCT). Purpose To conduct a RCT to examine whether contextualised data feedback delivered using a novel digital service, in conjunction with usual care (UC) promotes positive PA behavioural change, with direct comparison to UC alone. Methods This prospective, parallel group, open-label, RCT enrolled 130 patients eligible for CR and consisted of an 8-week intervention period with follow-up at 8-weeks. The intervention group received the novel digital CR service plus UC, with the control group receiving UC alone. The primary outcome was changes in PA to achieve the ACPICR guidelines. Both groups wore a PA monitor to collect minute-level energy expenditure data that underwent processing using a patented method to extract the specific PA metrics required for analysis. The secondary outcome was changes in CV fitness between pre and post assessments, measured using Incremental Shuttle Walk Test (ISWT). Results Patient characteristics are shown in Table 1. Adherence to data collection was good, with an average of 37 complete days (≥768 minutes per day) of PA data per person. Fifty-six intervention group patients and 49 control group patients were analysed for the primary outcome. A significant difference (p<0.025) in the probability of achieving the ACPICR ‘Daily Activity’ guideline was found between groups, with the intervention group more likely to achieve the guideline at week-8 versus control. Despite Covid-19 challenges, pre and post ISWT measurements were obtained for 33 intervention group patients and 37 control group patients. No significant differences between groups were found. However, the average improvement seen in the intervention group, +89 metres (m), exceeded the minimum clinically important difference for the ISWT (+70 m), and was more than double that seen in the control group, +44 m. Conclusion This RCT builds on previous evidence supporting the use of the novel digital service in CR[3]. Engagement with, and completion of, the digital CR service was excellent. Participation was associated with statistically significant improved PA in relation to ACPICR guidelines and clinically important increases in CV fitness versus UC alone.Table 1

Abstract 19055: Effectiveness of Mobile Health Applications for Exercise Promotion on Cardiorespiratory Fitness After a Cancer Diagnosis: A Systematic Review and Meta-Analysis

Introduction: Cancer survivors are at higher risk for cardiovascular (CV) related mortality. Smartphone application based (app-based) interventions that promote exercise and physical activity are an increasingly prevalent strategy for health promotion. Yet, whether these mobile health (mHealth) interventions improve CV risk after a cancer diagnosis is unknown. Methods: Leveraging MEDLINE/PubMed, Scopus, and Clinical Trials.gov, we identified studies through May 1, 2023. Literature searches were conducted on articles meeting study inclusion criteria and with reported cancer diagnoses. Search terms included smartphone , mobile health , mHealth , app , mobile application , exercise , cancer and cardio-oncology . The main outcomes and measures included change in cardiovascular fitness, reflected by 6-minute walk test (6MWT), VO2max, 3-minute step test and systolic blood pressure or any mention of cardiac measures. Effect sizes were calculated as Cohen’s d. Aggregate effect sizes and moderator variables were tested using random effects models. Results: Overall, from 656 articles, 7 randomized controlled trials (RCTs) with 341 participants were identified. Interventions included mobile apps (n = 6), smartwatches (n = 2), or smartwatch plus an option to also use a web, mobile, or tablet app (n = 1); median age 49.71± 5.9 years; median duration of mHealth use 12 weeks. Across the 7 RCTs, mHealth was associated with improved cardiorespiratory outcomes (Cohen’s d=0.33; 95% CI, 0.07-0.60). Results maintained significance when cholesterol outcomes were added to the other cardiorespiratory outcomes ( d = 0.30; 95% CI = 0.03-0.56). There was no heterogeneity ( Q = 5.86, P >0.05) or publication bias ( P > .05). Among the 4 studies examining the 6MWT, the between groups Δ Cohen’s d was 0.27 (95% CI, -0.21, 0.75). Conclusions: Smartphone app-based exercise promotion interventions appear to be a viable strategy for improving cardiorespiratory fitness after a cancer diagnosis.

Aerobic exercise is associated with region-specific changes in volumetric, tensor-based, and fixel-based measures of white matter integrity in healthy older adults

White matter integrity and cognition have been found to decline with advancing adult age. Aerobic exercise may be effective in counteracting these declines. Generally, white matter integrity has been quantified using a volumetric measure (WMV) and with tensor-based parameters, such as fractional anisotropy (FA) and mean diffusivity (MD), the validity of which appears to be compromised in the presence of crossing fibers. Fixel-based analysis techniques claim to overcome this problem by yielding estimates of fiber density (FD), cross-section (FC), and their product (FDC) in multiple directions per voxel. In a sample of 61 healthy older adults (63–76 years old), we quantified changes in white matter integrity following an aerobic exercise intervention with the commonly used volumetric and tensor-based metrics (WMV, FA, MD) and with fixel-based metrics (FD, FC, FDC). We investigated the associations of changes in these white matter parameters with changes in cardiovascular fitness and Digit Symbol Substitution task (DSST) performance, a marker of perceptual speed. In line with previous findings, we observed maintained WMV in the corpus callosum of exercisers, and positive change-change correlations between WMV and fitness, and between WMV and perceptual speed. For FA and MD, group differences in change opposite to those hypothesized were found in the corpus callosum, posterior corona radiata, and superior longitudinal fasciculus at an uncorrected significance threshold. Likewise, regions in superficial WM in the prefrontal cortex showed group differences in FD and FDC change, uncorrected, with more positive change in controls and more negative change in exercisers. Finally, changes in FD and FDC were found to be inversely correlated to changes in fitness and DSST performance. The present results corroborate previous findings of WMV changes, but cast doubt on current physiological interpretations of both tensor-based and fixel-based indicators of white matter properties in the context of exercise intervention studies.

Effect of COVID-19 Lockdown on Cardiovascular Health in University Students

A decrease in physical activity levels among university students during the COVID-19 pandemic is well-documented in the literature. However, the effect of lockdown restrictions on cardiovascular fitness has not been thoroughly investigated. The aim of the study was to assess the possible changes in cardiovascular fitness among university students during a 14-week period of the COVID-19 pandemic. Thirteen female and seven male tourism and recreation students participated in the study. Examinations were conducted in November 2020 and in February/March 2021. Students performed the PWC170 test on a cycling ergometer. Maximal oxygen consumption was calculated based on the PWC170 test results. Blood pressure and heart rate were measured at rest, as well as in the 1st and 5th minute of post-exercise recovery. No substantial changes were observed in maximal oxygen consumption level when comparing autumn and winter indices. Male students presented elevated blood pressure whereas female students presented normal blood pressure. Heart-rate and blood-pressure indices did not show substantial alternations in examined students during analyzed period. Fourteen weeks of lockdown had little effect on the cardiovascular health of tourism and recreation students.

Change in Latent Gray-Matter Structural Integrity Is Associated With Change in Cardiovascular Fitness in Older Adults Who Engage in At-Home Aerobic Exercise.

In aging humans, aerobic exercise interventions have been found to be associated with more positive or less negative changes in frontal and temporal brain areas, such as the anterior cingulate cortex (ACC) and hippocampus, relative to no-exercise control conditions. However, individual measures such as gray-matter (GM) probability may afford less reliable and valid conclusions about maintenance or losses in structural brain integrity than a latent construct based on multiple indicators. Here, we established a latent factor of GM structural integrity based on GM probability assessed by voxel-based morphometry, magnetization transfer saturation, and mean diffusivity. Based on this latent factor, we investigated changes in structural brain integrity during a six-month exercise intervention in brain regions previously reported in studies using volumetric approaches. Seventy-five healthy, previously sedentary older adults aged 63–76 years completed an at-home intervention study in either an exercise group (EG; n = 40) or in an active control group (ACG; n = 35). Measures of peak oxygen uptake (VO2peak) taken before and after the intervention revealed a time-by-group interaction, with positive average change in the EG and no reliable mean change in the ACG. Significant group differences in structural brain integrity changes were observed in the right and left ACC, right posterior cingulate cortex (PCC), and left juxtapositional lobule cortex (JLC). In all instances, average changes in the EG did not differ reliably from zero, whereas average changes in the ACG were negative, pointing to maintenance of structural brain integrity in the EG, and to losses in the ACG. Significant individual differences in change were observed for right ACC and left JLC. Following up on these differences, we found that exercising participants with greater fitness gains also showed more positive changes in structural integrity. We discuss the benefits and limitations of a latent-factor approach to changes in structural brain integrity, and conclude that aerobic fitness interventions are likely to contribute to brain maintenance in old age.

Factors Associated With Change in Cardiovascular Fitness for Patients With Peripheral and Coronary Artery Disease in Cardiac Rehabilitation.

Cardiac rehabilitation (CR) yields improvements in cardiorespiratory fitness (peak oxygen uptake [V˙o2peak]). Predictors of change in V˙o2peak have been reported among patients with coronary artery disease (CAD) but have not been compared with peripheral artery disease (PAD). This study determined predictors of improved V˙o2peak among patients with PAD, CAD, and concomitant PAD and CAD (PAD/CAD) following a 6-mo home-based outpatient CR program (1supervised and 4 home weekly sessions). This study was a retrospective (2006-2017) multiple linear regression analysis of CR patients with PAD (n = 63), CAD (n = 63), and PAD/CAD (n = 164). Peripheral artery disease and CAD were matched for age, sex, smoking status, diabetes, and year in program. Mean age of all patients was 68.9±10.1 yr, 72% were male, and mean improvement in V˙o2peak was 2.1 ± 3.3 mL/kg/min (14.5% improvement) following CR. In CAD, younger age (β = .30, P = .015), male sex (β = -.29, P = .019), and more recent year of entry (β = .26, P = .035) were predictors of improved V˙o2peak. In PAD, only male sex (β = -.36, P = .004) and in PAD/CAD, not having diabetes (β = -.24, P = .002), not smoking (β = -.25, P = .001), and shorter elapsed time from referring diagnosis to entry (β = -.19, P = .016) were predictors. While younger age and male sex were predictors of improved V˙o2peak in CAD, age did not influence PAD, and neither age nor sex influenced PAD/CAD. Peripheral artery disease-related limitations may override some demographic factors, and strategies for improving V˙o2peak should be explored. Managing smoking and comorbid diagnoses including diabetes and a timely entry to CR may yield greater improvements in V˙o2peak among individuals with PAD.

Effects of yoga, aerobic, and stretching and toning exercises on cognition in adult cancer survivors: protocol of the STAY Fit pilot randomized controlled trial

BackgroundCancer survivors experience compromised quality of life due to impaired cognitive function as a result of cancer diagnosis and treatment. Although exercise has proven to be effective in improving cognitive function across the lifespan, interventions comprehensively testing the effectiveness for cancer survivors are limited. The STAY Fit Trial is a three-armed pilot randomized controlled trial designed to compare the effects of a 12-week yoga, aerobic walking, and stretch and tone intervention on cognitive function among adult cancer survivors.MethodsThis pilot study aims to recruit 75 adult cancer survivors who will complete assessments of cognitive function, cardiovascular fitness, physical activity, and psychosocial measures at baseline and after the 12-week intervention. The aims of STAY Fit are (1) to assess the efficacy of yoga to improve cognitive function among cancer survivors, compared to aerobic exercise and an active control group; (2) to examine changes in cardiovascular fitness as a result of the interventions; and (3) to assess changes in quality of life among our population as a result of the exercise interventions.DiscussionThe STAY Fit Trial will test the effectiveness of yoga, aerobic exercise, and stretching and toning exercises in improving cognitive function and fitness among adult cancer survivors. The results of this pilot study will enable us to understand the most effective physical activity modality to improve cognitive function in this population and potentially combat cancer-related cognitive impairment.Trial registrationClinicalTrials.gov NCT03650322. Registered on 28 August 2018.

Abstract 018: New York City Youth Cardiovascular Fitness and Subsequent School Absenteeism Have an Inverse, Dose-Response Relationship, Regardless of How Poverty is Measured

Introduction: Recent research demonstrates that cardiovascular fitness improvements are associated with lower absenteeism, particularly for girls attending schools located in high poverty neighborhoods. Poverty at the student, school, and neighborhood levels may each have unique effects on both cardiovascular fitness and school absenteeism. There is a need to simultaneously explore the effects of poverty measures collected at different levels of observation on the longitudinal fitness-absenteeism relationship and across gender in order to inform policy targeting reduced school absenteeism. Hypothesis: It was hypothesized that poverty measured at the neighborhood level would have the strongest magnitude of effects on the cardiovascular fitness-absenteeism relationship compared with poverty measured at the school and student levels. Methods: Data for this study were drawn from the New York City Fitnessgram dataset. Inclusion criteria were enrollment in a New York City public school for at least 2 consecutive years in grades 6-8 (2006-2013) while attending a school that collected Fitnessgram measurements. Negative binomial longitudinal mixed models with random-intercepts were run to test the association between the exposure, child-specific change in cardiovascular fitness from the year prior, and the outcome, days absent the subsequent year. Separate crude and adjusted models were run stratified by student (individual household), school (percent of students living in poverty or qualifying for free/reduced price school meals) and neighborhood (home- and school-area) poverty measures, and also by gender. Models were adjusted for individual- and group-level confounders (time, grade, race/ethnicity, place of birth, change in obesity status, and school size), and clustering by individual student and school. Results: The sample included 360,743 students (67% black or Hispanic, 51% male, 69% qualifying for free/reduced price school meals). Adjusted estimates showed an inverse-dose response fitness-absenteeism relationship across all poverty measures, with the highest magnitude of effects for youth attending schools in high poverty neighborhoods (IRR= -0.12, 95%CI: -0.20, -0.04 in girls; IRR= -.13, 95%CI: -.29, .03 in boys), and in girls attending schools with a high proportion of students qualifying for free/reduced school meals (IRR= -.11, 95%CI: -.23, -.01). Conclusions: In conclusion, there is an inverse, dose-response trend between cardiovascular fitness and subsequent absenteeism in high poverty youth, regardless of how poverty is measured, and particularly among girls. Future research should examine the potential for distinct youth physical activity interventions tailored to the individual, school and neighborhood levels to reduce school absenteeism associated with poverty.

Relationship Between Cardiorespiratory Fitness, Weight Status, and Academic Performance: Longitudinal Evidence From 1 School District.

We examined the longitudinal relationship between cardiovascular fitness (CRF) and academic performance (AP) among students in a diverse public school district. Furthermore, we determined whether the relationship between CRF and AP varied by student sociodemographic characteristics. This study used data from 2005-2006 to 2008-2009. AP was assessed by Massachusetts Comprehensive Assessment System (MCAS) math (N = 1224) and English Language Arts (ELA) (N = 1248) z-scores. CRF was assessed by an age- and sex-adjusted 20-yard shuttle run (pass/fail). Multilevel growth models were used to estimate the relationship between MCAS z-scores and changes in grade, CRF, and weight status, controlling for student sociodemographic characteristics. Students who passed the fitness test performed better on MCAS tests (ELA: .159, p < .001; Math: 0.346, p < .001) at each study wave relative to those who did not pass. The relationship between AP and fitness was attenuated for low socioeconomic status(ELA: -.111, p < .05) and minority (Math: black -0.249, p < .01; Latino -0.216, p < .01) students. These results add to the literature highlighting the role of CRF as an important predictor of performance on standardized tests. More research is needed to understand the disparities experienced by low-income and minority students.

Maintenance of improvements in fitness and fatness 1 year after a 3-month lifestyle intervention in overweight men.

Sustained improvements in cardiovascular fitness and body composition after lifestyle interventions are challenging. The present study investigated whether changes in cardiovascular fitness and body composition were maintained for up to 1 year after similar exercise-induced (T) or diet-induced weight loss (D) or exercise without weight loss (T-iD) in overweight sedentary men. Six and 12 months after the interventions, we measured cardiovascular fitness and body composition. Cardiovascular fitness was higher at both 6- (3.2±1.5 ml O2/kg/min, P=0.053) and 12-month follow-up (3.9±1.4 ml O2/kg/min, P=0.049) compared with pre-intervention in T. Fat mass (-3.0±1.2 kg, P=0.04) and abdominal fat (-3.6±1.5%, P=0.04) were lower within T at 12-month follow-up compared with pre-intervention. This did not occur in D (P>0.13) or T-iD (P>0.14), although body weight was lower in D (-2.5±2.2 kg, P=0.09). This study showed that fitness and fatness were not returned to pre-intervention levels 1 year after a 3-month exercise-induced weight-loss intervention.

Randomized controlled trial of exercise interventions to improve sleep quality and daytime sleepiness in individuals with multiple sclerosis: A pilot study.

BackgroundNearly 70% of individuals with multiple sclerosis (MS) experience sleep disturbances. Increasing physical activity in people with MS has been shown to produce a moderate improvement in sleep quality, and exercise has been shown to improve sleep quality in non-neurologically impaired adults.ObjectiveThe purpose of this pilot randomized controlled trial study was to examine the effect of two exercise interventions on sleep quality and daytime sleepiness in individuals with MS.MethodsTwenty-eight individuals with relapsing–remitting or secondary progressive MS were randomized into one of two 12-week exercise interventions: a supervised, moderate-intensity aerobic exercise (AE) program or an unsupervised, low-intensity walking and stretching (WS) program. Only individuals who were ≥ 70% compliant with the programs were included in analysis (n = 12 AE; n = 10 WS).ResultsBoth groups demonstrated a moderate improvement in sleep quality, although only the improvement by the WS group was statistically significant. Only the AE group demonstrated a significant improvement in daytime sleepiness. Change in sleep quality and daytime sleepiness was not correlated with disease severity or with change in cardiovascular fitness, depression, or fatigue.ConclusionThe mechanisms for improvement in sleep quality and daytime sleepiness need further investigation, but may be due to introduction of zeitgebers to improve circadian rhythm.

Exercise videogames for physical activity and fitness: Design and rationale of the Wii Heart Fitness trial

IntroductionDespite numerous health benefits, less than half of American adults engage in regular physical activity. Exercise videogames (EVG) may be a practical and attractive alternative to traditional forms of exercise. However there is insufficient research to determine whether EVG play alone is sufficient to produce prolonged engagement in physical activity or improvements in cardiovascular fitness and overall health risk. The goal of the present study is to test the efficacy of exercise videogames to increase time spent in moderate to vigorous physical activity (MVPA) and to improve cardiovascular risk indices among adults. MethodsWii Heart Fitness is a rigorous 3-arm randomized controlled trial with adults comparing three 12-week programs: (1) supervised EVGs, (2) supervised standard exercise, and (3) a control condition. Heart rate is monitored continuously throughout all exercise sessions. Assessments are conducted at baseline, end of intervention (week 12), 6 and 9months. The primary outcome is time spent in MVPA physical activity. Secondary outcomes include changes in cardiovascular fitness, body composition, blood lipid profiles and maintenance of physical activity through six months post-treatment. Changes in cognitive and affective constructs derived from Self Determination and Social Cognitive Theories will be examined to explain the differential outcomes between the two active treatment conditions. ConclusionThe Wii Heart Fitness study is designed to test whether regular participation in EVGs can be an adequate source of physical activity for adults. This study will produce new data on the effect of EVGs on cardiovascular fitness indices and prolonged engagement with physical activity.

The effects of exercise training in addition to energy restriction on functional capacities and body composition in obese adults during weight loss: a systematic review.

BackgroundObesity is associated with impairments of physical function, cardiovascular fitness, muscle strength and the capacity to perform activities of daily living. This review examines the specific effects of exercise training in relation to body composition and physical function demonstrated by changes in cardiovascular fitness, and muscle strength when obese adults undergo energy restriction.MethodsElectronic databases were searched for randomised controlled trials comparing energy restriction plus exercise training to energy restriction alone. Studies published to May 2013 were included if they used multi-component methods for analysing body composition and assessed measures of fitness in obese adults.ResultsFourteen RCTs met the inclusion criteria. Heterogeneity of study characteristics prevented meta-analysis. Energy restriction plus exercise training was more effective than energy restriction alone for improving cardiovascular fitness, muscle strength, and increasing fat mass loss and preserving lean body mass, depending on the type of exercise training.ConclusionAdding exercise training to energy restriction for obese middle-aged and older individuals results in favourable changes to fitness and body composition. Whilst weight loss should be encouraged for obese individuals, exercise training should be included in lifestyle interventions as it offers additional benefits.

Effects of exercise and lifestyle modification on fitness, insulin resistance, skeletal muscle oxidative phosphorylation and intramyocellular lipid content in obese children and adolescents

Obesity is associated with poor fitness and adverse metabolic consequences in children. To investigate how exercise and lifestyle modification may improve fitness and insulin sensitivity in this population. Randomized controlled trial, 21 obese (body mass index ≥ 95% percentile) subjects, ages 10 to 17 years. Subjects were given standardized healthful lifestyle advice for 8 weeks. In addition, they were randomized to an in-home supervised exercise intervention (n = 10) or control group (n = 11). Fasting laboratory studies (insulin, glucose, lipid profile) and assessments of fitness, body composition, skeletal muscle oxidative phosphorylation and intramyocellular lipid content (IMCL), were performed at baseline and study completion. Subjects were 13.0 ± 1.9 (standard deviation) years old, 72% female and 44% non-white. Exercise improved fitness (P = 0.03) and power (P = 0.01), and increased IMCL (P = 0.02). HOMA-IR decreased among all subjects in response to lifestyle modification advice (P = 0.01), regardless of exercise training assignment. In univariate analysis in all subjects, change in cardiovascular fitness was associated with change in HOMA-IR. In exploratory analyses, increased IMCL was associated with greater resting energy expenditure (r = 0.78, P = 0.005) and a decrease in fasting respiratory quotient (r = -0.70, P = 0.02) (n = 11). Change in fitness was found to be related to change in insulin resistance in response to lifestyle modification and exercise in obese children. IMCL increased with exercise in these obese children, which may reflect greater muscle lipid oxidative capacity.

Longer Length of First Stay in Intermittent Residential Programmes Is Associated with Larger Weight Loss at 1 and 2 Years

Objective: To determine if length of first stay impacts on weight loss and cardiovascular fitness, at 1 and 2 years in severely obese patients enrolled in intermittent residential programs. Methods: In a retrospective follow-up study, we assessed weight loss and changes in cardiovascular fitness (VO₂ peak) at 1 and 2 years in 179 severely obese adults who participated in two intermittent residential programmes. Both programmes consisted of five stays at the Røros Rehabilitation Centre over a 2-year period, but programme A consisted of a much longer first stay compared with programme B (8 vs. 2 weeks). Results: Of 179 participants (BMI 44 ± 6 kg/m²), 162 completed 1-year and 117 2-year evaluation. Programme A led to significantly larger weight reduction (-20.7 ± 10.8 vs. -13.5 ± 8.1 kg and -16.0 ± 12.7 vs. -7.9 ± 11.2 kg, p < 0.0001) and improvement in VO₂ peak (7.8 vs. 3.6 ml/kg/min (p < 0.0001) and 5.6 vs. 2.5 ml/kg/min (p < 0.01)) at both 1 and 2 years, compared with programme B. Intention-to-treat analysis showed similar results. Conclusion: A residential intermittent programme with a longer initial stay is associated with better weight loss and improvement in cardiovascular fitness at both 1 and 2 years. A longer follow-up is needed to clearly establish the sustainability of these programmes.

Prospective BMI category change associated with cardiovascular fitness change.

The objective of this study was to test the relationship of change in body mass index (BMI) percentile score group (from sixth to eighth grade) with change in cardiovascular fitness (CVF), baseline BMIz-score, and CVF. Children (3998 (92%)) in the HEALTHY trial provided complete data at the beginning of sixth and end of eighth grades. Height and weight were assessed according to standardized protocol. CVF was measured using the 20-m shuttle run. Changes in BMI percentile were categorized into five groups: increased a BMI category, stayed obese, stayed overweight, stayed at a healthy weight, and decreased a BMI category. Data were analyzed separately by sex, controlling for race, parental education, change in pubertal stage, and baseline BMIz-score and CVF. Youth (male and female) who lowered their BMI group or remained in the healthy or overweight groups had significantly larger increases in CVF than those in the stayed obese or increased a BMI category groups. However, these relationships accounted for a small percentage of variance (i.e., weak relationship). Staying obese was associated with the highest baseline BMIz-score, with the second highest among those who decreased a BMI category. BMI category change accounted for the most variance in baseline BMIz-score. Changes in BMI categories were substantially more strongly related to sixth-grade values of BMIz-score than to CVF changes. Because preexisting adiposity may inhibit adiposity change, changes in CVF and adiposity should be attempted before middle school.

Adherence to a cardiac rehabilitation home program model of care: a comparison to a well-established traditional on-site supervised program

Despite the proven benefits of cardiac rehabilitation (CR), adherence to programs remains suboptimal. To improve adherence, alternative models of care, such as using home programs (HP), have been recommended. Little information exists, however, about its effect on adherence in real-world settings. Therefore, this study's primary objective was to compare adherence of patients in an HP and traditional on-site program (TP) model of CR. The secondary objective was to compare their clinical and demographic profiles and changes in cardiovascular fitness. We implemented a retrospective review of 200 consecutively enrolled patients who chose either a TP or HP model. Profile data was collected at intake assessment. Adherence, defined as attendance to prescheduled contacts or on-site visits in each respective cohort, served as a primary outcome measure. Secondary outcomes included completion of program and cardiopulmonary fitness levels at 6months. We found that the HP cohort had patients who were significantly younger, male (significantly moreso than female), were more geographically removed from the on-site centre, were employed, and (or) had greater cardiopulmonary fitness at initiation. Similar mean attendance (p = 0.21) and completion rates (p = 0.22) were seen between models. Both groups attained similar gains in cardiovascular fitness (p = 0.79). Analysis of adherence shows the HP to be a suitable option for patients who face barriers for TP-CR participation.

Changes in cardiorespiratory fitness in cardiac rehabilitation patients: A meta-analysis

Background/objectivesImproving patients' cardiorespiratory fitness is an important therapeutic outcome in cardiac rehabilitation. The ability of cardiac rehabilitation to reduce mortality and morbidity has been evidenced through several meta-analyses. Whether cardiac rehabilitation can increase cardiorespiratory fitness and which factors may influence such gains are less well quantified. MethodsWe performed detailed literature searches of electronic databases and manually searched papers concerning changes in cardiorespiratory fitness in cardiac rehabilitation patients. We performed random-effects meta-analysis of mean improvements in cardiorespiratory fitness and subgroup analyses to determine potential sources of heterogeneity. ResultsData from 31 studies produced 48 groups (n=3827) with a mean improvement of 1.55 (95% CI 1.21–1.89) METs, (p<0.001); equivalent to standardised effect size of ES=0.97 (95% CI 0.80–1.13). As this value was highly heterogeneous (Q=852, p<0.001) we performed subgroup analyses on the effect size data. Gains in fitness were highest in patients receiving >36 exercise sessions in studies where fitness was assessed using the Naughton Protocol. Patient characteristics associated with the highest fitness gains were age (being young) and sex (being male training in a male-only exercise group). Changes in fitness were unrelated to programme type (comprehensive or exercise-only), duration or study design. There was no association with patient's baseline fitness levels. ConclusionThis is the first meta-analysis of changes in cardiovascular fitness in cardiac rehabilitation patients and shows clinically significant improvements in a large sample of patients from a variety of rehabilitation programmes. This analysis helps describe the characteristics of cardiac rehabilitation programmes which can increase patients' cardiorespiratory fitness.

Cardiovascular fitness modulates brain activation associated with spatial learning

Aerobic exercise has beneficial effects on cognitive functioning in aging humans, especially on executive functions associated with frontal brain regions. In rodents, exercise has been shown to induce structural and neurophysiological changes especially in the hippocampus and to improve spatial learning. The present study investigated the relationship between cardiovascular fitness, spatial learning and associated patterns of brain activation cross-sectionally and longitudinally in a sample of middle-aged men and women (40-55 years) that took part in a six-month exercise intervention and an additional spatial training. Spatial learning capacities before and after the interventions were measured with a virtual maze task. During this task, participants were repeatedly moved through a virtual town and were instructed to infer the spatial layout of the environment. Brain activations during encoding of the virtual town were assessed with functional magnetic resonance imaging (fMRI). The fMRI data revealed that brain activations during successful spatial learning were modulated by the individual fitness level in a neural network, comprising the hippocampus, retrosplenial cortex, cuneus, precuneus, parahippocampal gyrus, caudate nucleus, insula, putamen, and further frontal, temporal, occipital and cingulate regions. Moreover, physical exercising induced changes in cardiovascular fitness that correlated positively with changes in brain activations in the medial frontal gyrus and the cuneus. However, overall spatial learning performance did not vary with cardiovascular fitness. These data suggest that cardiovascular fitness has an impact on brain regions associated with spatial learning in humans and hence, could be a potent intervention to prevent age-related cognitive decline.

Submaximal Step-Testing as a Tool to Assess Cardiovascular Fitness in Youth Who Are Obese

INTRODUCTION: Youth who are obese typically have lower cardiovascular fitness levels than their normal weight peers. The greater amount of body fat for children who are obese coupled with a generally decreased amount of physical activity oftentimes limits their ability to reach true maximal values during maximal exercise testing. Submaximal testing was therefore evaluated as a novel tool to better assess cardiovascular fitness among children who are obese. PURPOSE:To use submaximal testing to measure changes in cardiovascular fitness in youth who are obese following METHODS:This pilot study was comprised of a subsample of children who were obese and consecutively enrolled in Healthy Kids, Healthy Weight, a weight management program at Rainbow Babies & Children's Hospital in Cleveland, Ohio. The participants were 29 children between the ages of 7 to 18 years (13 males, 16 females). The submaximal test was performed at the initial fitness visit and again on the last night of the 12-week intervention. Each child performed the 3-minute YMCA step-test. The child stepped up and down on a 30cm bench for 3 minutes at a cadence of 96 beats per minute, set by metronome. Within 5 seconds following the last beat, the child was seated and heart rate was palpated for 60 seconds via radial pulse. The number of beats per minute (BPM) was recorded. RESULTS:BPM decreased significantly from baseline to end of intervention (112.3 bpm vs. 106.0 bpm; p=0.02) as did BMI (p=0.02) and BMI z-score (p=0.006). Change in cardiovascular fitness, as measured by change in BPM, was significantly associated with baseline heart rate (r=-.53, p=0.003); the higher the baseline BPM, the greater the decrease was from baseline to end of intervention. There were no significant associations between BPM change and age, gender, or baseline BMI or BMI z-score change. CONCLUSIONS: Submaximal step testing may be a useful tool for determining changes in cardiovascular fitness among treatment-seeking children who are obese. Cardiovascular fitness, BMI, and BMI z-score change in these children significantly improved following a 12-week, multi-disciplinary intervention, with greatest improvements in BPM among children with lowest cardiovascular fitness at baseline.