Resistance Exercise Training in Individuals With and Without Cardiovascular Disease: 2023 Update: A Scientific Statement From the American Heart Association.

Resistance training not only can improve or maintain muscle mass and strength, but also has favorable physiological and clinical effects on cardiovascular disease and risk factors. This scientific statement is an update of the previous (2007) American Heart Association scientific statement regarding resistance training and cardiovascular disease. Since 2007, accumulating evidence suggests resistance training is a safe and effective approach for improving cardiovascular health in adults with and without cardiovascular disease. This scientific statement summarizes the benefits of resistance training alone or in combination with aerobic training for improving traditional and nontraditional cardiovascular disease risk factors. We also address the utility of resistance training for promoting cardiovascular health in varied healthy and clinical populations. Because less than one-third of US adults report participating in the recommended 2 days per week of resistance training activities, this scientific statement provides practical strategies for the promotion and prescription of resistance training.

A New Era in Cardiac Rehabilitation Delivery: Research Gaps, Questions, Strategies, and Priorities.

Cardiac rehabilitation (CR) is a guideline-recommended, multidisciplinary program of exercise training, risk factor management, and psychosocial counseling for people with cardiovascular disease (CVD) that is beneficial but underused and with substantial disparities in referral, access, and participation. The emergence of new virtual and remote delivery models has the potential to improve access to and participation in CR and ultimately improve outcomes for people with CVD. Although data suggest that new delivery models for CR have safety and efficacy similar to traditional in-person CR, questions remain regarding which participants are most likely to benefit from these models, how and where such programs should be delivered, and their effect on outcomes in diverse populations. In this review, we describe important gaps in evidence, identify relevant research questions, and propose strategies for addressing them. We highlight 4 research priorities: (1) including diverse populations in all CR research; (2) leveraging implementation methodologies to enhance equitable delivery of CR; (3) clarifying which populations are most likely to benefit from virtual and remote CR; and (4) comparing traditional in-person CR with virtual and remote CR in diverse populations using multicenter studies of important clinical, psychosocial, and cost-effectiveness outcomes that are relevant to patients, caregivers, providers, health systems, and payors. By framing these important questions, we hope to advance toward a goal of delivering high-quality CR to as many people as possible to improve outcomes in those with CVD.

Supervised Exercise Training for Chronic Heart Failure With Preserved Ejection Fraction: A Scientific Statement From the American Heart Association and American College of Cardiology.

Heart failure with preserved ejection fraction (HFpEF) is one of the most common forms of heart failure; its prevalence is increasing, and outcomes are worsening. Affected patients often experience severe exertional dyspnea and debilitating fatigue, as well as poor quality of life, frequent hospitalizations, and a high mortality rate. Until recently, most pharmacological intervention trials for HFpEF yielded neutral primary outcomes. In contrast, trials of exercise-based interventions have consistently demonstrated large, significant, clinically meaningful improvements in symptoms, objectively determined exercise capacity, and usually quality of life. This success may be attributed, at least in part, to the pleiotropic effects of exercise, which may favorably affect the full range of abnormalities-peripheral vascular, skeletal muscle, and cardiovascular-that contribute to exercise intolerance in HFpEF. Accordingly, this scientific statement critically examines the currently available literature on the effects of exercise-based therapies for chronic stable HFpEF, potential mechanisms for improvement of exercise capacity and symptoms, and how these data compare with exercise therapy for other cardiovascular conditions. Specifically, data reviewed herein demonstrate a comparable or larger magnitude of improvement in exercise capacity from supervised exercise training in patients with chronic HFpEF compared with those with heart failure with reduced ejection fraction, although Medicare reimbursement is available only for the latter group. Finally, critical gaps in implementation of exercise-based therapies for patients with HFpEF, including exercise setting, training modalities, combinations with other strategies such as diet and medications, long-term adherence, incorporation of innovative and more accessible delivery methods, and management of recently hospitalized patients are highlighted to provide guidance for future research.

Reduced Body Flexibility Is Associated With Poor Survival in Middle-Aged Men and Women: A Prospective Cohort Study.

OBJECTIVES: Flexibility is recognized as one of the components of physical fitness and commonly included as part of exercise prescriptions for all ages. However, limited data exist regarding the relationship between flexibility and survival. We evaluated the sex-specific nature and magnitude of the associations between body flexibility and natural and non-COVID-19 mortality in a middle-aged cohort of men and women. DESIGN: Prospective cohort study. METHODS: Anthropometric, health and vital data from 3139 (66% men) individuals aged 46-65 years spanning from March 1994 to October 2022 were available. A body flexibility score, termed Flexindex, was derived from a combination of 20 movements (scored 0-4) involving seven different joints, resulting in a score range of 0-80. Kaplan-Meier survival curves were obtained, and unadjusted and adjusted hazard ratios (HRs) for mortality estimated. RESULTS: During a mean follow-up of 12.9 years, 302 individuals (9.6%) comprising 224 men/78 women died. Flexindex was 35% higher in women compared to men (mean ± SD: 41.1 ± 9.4 vs. 30.5 ± 8.7; p < 0.001) and exhibited an inverse relationship with mortality risk in both sexes (p < 0.001). Following adjustment for age, body mass index, and health status, the HR (95% CI) for mortality comparing upper and bottom of distributions of Flexindex were 1.87 (1.50-2.33; p < 0.001) for men and 4.78 (1.23-31.71; p = 0.047) for women. CONCLUSIONS: A component of physical fitness-body flexibility-as assessed by the Flexindex is strongly and inversely associated with natural and non-COVID-19 mortality risk in middle-aged men and women. Future studies should assess whether training-induced flexibility gains are related to longer survival.

Exercise-Related Acute Cardiovascular Events and Potential Deleterious Adaptations Following Long-Term Exercise Training: Placing the Risks Into Perspective-An Update: A Scientific Statement From the American Heart Association.

Epidemiological and biological plausibility studies support a cause-and-effect relationship between increased levels of physical activity or cardiorespiratory fitness and reduced coronary heart disease events. These data, plus the well-documented anti-aging effects of exercise, have likely contributed to the escalating numbers of adults who have embraced the notion that "more exercise is better." As a result, worldwide participation in endurance training, competitive long distance endurance events, and high-intensity interval training has increased markedly since the previous American Heart Association statement on exercise risk. On the other hand, vigorous physical activity, particularly when performed by unfit individuals, can acutely increase the risk of sudden cardiac death and acute myocardial infarction in susceptible people. Recent studies have also shown that large exercise volumes and vigorous intensities are both associated with potential cardiac maladaptations, including accelerated coronary artery calcification, exercise-induced cardiac biomarker release, myocardial fibrosis, and atrial fibrillation. The relationship between these maladaptive responses and physical activity often forms a U- or reverse J-shaped dose-response curve. This scientific statement discusses the cardiovascular and health implications for moderate to vigorous physical activity, as well as high-volume, high-intensity exercise regimens, based on current understanding of the associated risks and benefits. The goal is to provide healthcare professionals with updated information to advise patients on appropriate preparticipation screening and the benefits and risks of physical activity or physical exertion in varied environments and during competitive events.

Home-Based Cardiac Rehabilitation: A Scientific Statement From the American Association of Cardiovascular and Pulmonary Rehabilitation, the American Heart Association, and the American College of Cardiology.

Cardiac rehabilitation (CR) is an evidence-based intervention that uses patient education, health behavior modification, and exercise training to improve secondary prevention outcomes in patients with cardiovascular disease. CR programs reduce morbidity and mortality rates in adults with ischemic heart disease, heart failure, or cardiac surgery but are significantly underused, with only a minority of eligible patients participating in CR in the United States. New delivery strategies are urgently needed to improve participation. One potential strategy is home-based CR (HBCR). In contrast to center-based CR services, which are provided in a medically supervised facility, HBCR relies on remote coaching with indirect exercise supervision and is provided mostly or entirely outside of the traditional center-based setting. Although HBCR has been successfully deployed in the United Kingdom, Canada, and other countries, most US healthcare organizations have little to no experience with such programs. The purpose of this scientific statement is to identify the core components, efficacy, strengths, limitations, evidence gaps, and research necessary to guide the future delivery of HBCR in the United States. Previous randomized trials have generated low- to moderate-strength evidence that HBCR and center-based CR can achieve similar improvements in 3- to 12-month clinical outcomes. Although HBCR appears to hold promise in expanding the use of CR to eligible patients, additional research and demonstration projects are needed to clarify, strengthen, and extend the HBCR evidence base for key subgroups, including older adults, women, underrepresented minority groups, and other higher-risk and understudied groups. In the interim, we conclude that HBCR may be a reasonable option for selected clinically stable low- to moderate-risk patients who are eligible for CR but cannot attend a traditional center-based CR program.

Cardio-Oncology Rehabilitation to Manage Cardiovascular Outcomes in Cancer Patients and Survivors: A Scientific Statement From the American Heart Association.

Cardiovascular disease is a competing cause of death in patients with cancer with early-stage disease. This elevated cardiovascular disease risk is thought to derive from both the direct effects of cancer therapies and the accumulation of risk factors such as hypertension, weight gain, cigarette smoking, and loss of cardiorespiratory fitness. Effective and viable strategies are needed to mitigate cardiovascular disease risk in this population; a multimodal model such as cardiac rehabilitation may be a potential solution. This statement from the American Heart Association provides an overview of the existing knowledge and rationale for the use of cardiac rehabilitation to provide structured exercise and ancillary services to cancer patients and survivors. This document introduces the concept of cardio-oncology rehabilitation, which includes identification of patients with cancer at high risk for cardiac dysfunction and a description of the cardiac rehabilitation infrastructure needed to address the unique exposures and complications related to cancer care. In this statement, we also discuss the need for future research to fully implement a multimodal model of cardiac rehabilitation for patients with cancer and to determine whether reimbursement of these services is clinically warranted.

Mediating effects of exercise capacity on the association between physical activity and health-related quality of life among adolescents with complex congenital heart disease.

OBJECTIVES: There is little evidence on interrelationships between physical activity, sedentary behaviors, and health-related quality of life (HRQOL) among adolescents with congenital heart disease (CHD). We hypothesized that exercise capacity would have a mediating effect on the associations of either physical activity or sedentary behavior with HRQOL. METHODS: Adolescents with complex CHD (n = 111) were consecutively recruited from an outpatient clinic in a general hospital in South Korea. Physical activity and sedentary behavior were assessed using the global physical activity questionnaire. Exercise capacity was directly measured by peak oxygen uptake using a symptom-limited maximal treadmill exercise test. HRQOL was evaluated by both adolescents and their parents using the Pediatric Quality of Life Inventory questionnaire. RESULTS: The self-reported and parent proxy-reported HRQOL were positively associated with physical activity (ß = 0.16, P = .003; ß = 0.12, P = .049) and exercise capacity (ß = 0.63, P < .001; ß = 0.66, P < .001), but not with sedentary behavior in adjusted regression models. When both variables were entered in the same regression models, only exercise capacity remained significantly associated with the self-reported (ß = 0.50, P = .008) and parent proxy-reported HRQOL (ß = 0.62, P = .003). Exercise capacity acted as a full mediator variable on the relationship between physical activity and HRQOL (P < .05 for both). CONCLUSIONS: The present findings suggest that exercise capacity mediates the association between physical activity and HRQOL, highlighting the importance of improving exercise capacity to potentially enhance HRQOL in adolescents with complex CHD.

Cardioprotective Exercise and Pharmacologic Interventions as Complementary Antidotes to Cardiovascular Disease.

Exercise and pharmacologic therapies to prevent and treat cardiovascular disease have advanced largely through independent efforts. Understanding of first-line drug therapies, findings from preclinical animal studies, and the need for research initiatives related to complementary cardioprotective exercise-pharma interventions are reviewed from the premise that contemporary cardioprotective therapies must include adjunctive exercise and lifestyle interventions in addition to pharmacologic agents.

Importance of Assessing Cardiorespiratory Fitness in Clinical Practice: A Case for Fitness as a Clinical Vital Sign: A Scientific Statement From the American Heart Association.

Mounting evidence has firmly established that low levels of cardiorespiratory fitness (CRF) are associated with a high risk of cardiovascular disease, all-cause mortality, and mortality rates attributable to various cancers. A growing body of epidemiological and clinical evidence demonstrates not only that CRF is a potentially stronger predictor of mortality than established risk factors such as smoking, hypertension, high cholesterol, and type 2 diabetes mellitus, but that the addition of CRF to traditional risk factors significantly improves the reclassification of risk for adverse outcomes. The purpose of this statement is to review current knowledge related to the association between CRF and health outcomes, increase awareness of the added value of CRF to improve risk prediction, and suggest future directions in research. Although the statement is not intended to be a comprehensive review, critical references that address important advances in the field are highlighted. The underlying premise of this statement is that the addition of CRF for risk classification presents health professionals with unique opportunities to improve patient management and to encourage lifestyle-based strategies designed to reduce cardiovascular risk. These opportunities must be realized to optimize the prevention and treatment of cardiovascular disease and hence meet the American Heart Association's 2020 goals.

Changes in cardiorespiratory fitness predict incident hypertension: A population-based long-term study.

OBJECTIVES: We investigated whether long-term changes in cardiorespiratory fitness (CRF) predict the risk of incident hypertension, independent of risk factors, in initially normotensive men. METHODS: This prospective study from the Kuopio Ischemic Heart Disease Study included 431 male participants without hypertension who underwent symptom-limited maximal cardiopulmonary exercise testing at baseline and during a second examination, 11-years later, who were re-evaluated for hypertension at 20-year follow-up. Changes in CRF (%) were calculated as the difference in directly measured maximal oxygen uptake (VO2max ) between the baseline and second examination, and classified into decreasing tertiles as percentages. Hypertension was defined as systolic and/or diastolic blood pressure ≥140/90 mmHg or hypertension that required antihypertensive medication as diagnosed by a physician. RESULTS: During a 10-year follow-up after the second examination, 165 men (38%) developed hypertension. Men who demonstrated the largest decline in CRF between evaluations (-62.1% to -20.2%) had a 4.33-fold (95% CI 2.32-8.07, P < .001) risk of incident hypertension compared to men with the smallest decrease or improvement in CRF (-8.8% to 82.0%), after adjusting for age, follow-up duration, alcohol consumption, cigarette smoking, serum low and high density lipoprotein cholesterol, body mass index, daily energy expenditure (kcal) via physical activity, glomerular filtration rate, and baseline systolic blood pressure and VO2max . CONCLUSIONS: The present findings indicate that more marked decreases in measured CRF over time are independently associated with the risk of incident hypertension in men, suggesting that CRF should be considered a causal risk factor to predict future hypertension.

Reliability and Accuracy of a Standardized Shallow Water Running Test to Determine Cardiorespiratory Fitness.

A standardized fitness assessment is critical for the development of an individualized exercise prescription. Although the benefits of aquatic exercise have been well established, there remains the need for a standardized nonswimming protocol to accurately assess cardiorespiratory fitness (CRF) in shallow water. The present investigation was designed to assess (a) the reliability of a standardized shallow water run (SWR) test of CRF and (b) the accuracy of a standardized SWR compared with a land-based treadmill (LTM) test. Twenty-three healthy women (20 ± 3 years), with body mass index (23.5 ± 3 kg·m), performed 2 shallow water peak oxygen consumption (V[Combining Dot Above]O2peak) running tests (SWRa and SWRb), and 1 V[Combining Dot Above]O2max LTM. Intraclass correlation coefficients indicated moderately strong reliability for V[Combining Dot Above]O2peak (ml·kg·min) (r = 0.73, p < 0.01), HRpeak (b·min) (r = 0.82; p < 0.01), and O2pulse (V[Combining Dot Above]O2 [ml·kg·min]·HR [b·min]) (r = 0.77, p < 0.01). Using paired t-tests and Pearson's correlations, SWR V[Combining Dot Above]O2peak and HRpeak were significantly lower than during LTM (p ≤ 0.05) and showed moderate correlations of 0.60 and 0.58 (p < 0.001) to LTM. O2pulse was similar (p > 0.05) for the SWR and LTM tests with a moderate correlation of 0.63. A standardized SWR test as a measure of CRF is a reliable, and to some degree, valid alternative to conventional protocols and may be used by strength and conditioning professionals to measure program outcomes and monitor training progress. Furthermore, this protocol provides a water-based option for CRF assessment among healthy women and offers insight toward the development of an effective protocol that can accommodate individuals with limited mobility, or those seeking less musculoskeletal impact from traditional land-based types of training.

Call to Action on Making Physical Activity Assessment and Prescription a Medical Standard of Care.

The U.S. population is plagued by physical inactivity, lack of cardiorespiratory fitness, and sedentary lifestyles, all of which are strongly associated with the emerging epidemic of chronic disease. The time is right to incorporate physical activity assessment and promotion into health care in a manner that engages clinicians and patients. In April 2015, the American College of Sports Medicine and Kaiser Permanente convened a joint consensus meeting of subject matter experts from stakeholder organizations to discuss the development and implementation of a physical activity vital sign (PAVS) to be obtained and recorded at every medical visit for every patient. This statement represents a summary of the discussion, recommendations, and next steps developed during the consensus meeting. Foremost, it is a "call to action" for current and future clinicians and the health care community to implement a PAVS in daily practice with every patient.

Physical activity and exercise recommendations for stroke survivors: a statement for healthcare professionals from the American Heart Association/American Stroke Association.

PURPOSE: This scientific statement provides an overview of the evidence on physical activity and exercise recommendations for stroke survivors. Evidence suggests that stroke survivors experience physical deconditioning and lead sedentary lifestyles. Therefore, this updated scientific statement serves as an overall guide for practitioners to gain a better understanding of the benefits of physical activity and recommendations for prescribing exercise for stroke survivors across all stages of recovery. METHODS: Members of the writing group were appointed by the American Heart Association Stroke Council's Scientific Statement Oversight Committee and the American Heart Association's Manuscript Oversight Committee. The writers used systematic literature reviews, references to published clinical and epidemiology studies, morbidity and mortality reports, clinical and public health guidelines, authoritative statements, personal files, and expert opinion to summarize existing evidence and indicate gaps in current knowledge. RESULTS: Physical inactivity after stroke is highly prevalent. The assessed body of evidence clearly supports the use of exercise training (both aerobic and strength training) for stroke survivors. Exercise training improves functional capacity, the ability to perform activities of daily living, and quality of life, and it reduces the risk for subsequent cardiovascular events. Physical activity goals and exercise prescription for stroke survivors need to be customized for the individual to maximize long-term adherence. CONCLUSIONS: The recommendation from this writing group is that physical activity and exercise prescription should be incorporated into the management of stroke survivors. The promotion of physical activity in stroke survivors should emphasize low- to moderate-intensity aerobic activity, muscle-strengthening activity, reduction of sedentary behavior, and risk management for secondary prevention of stroke.

2023 update: The importance of cardiorespiratory fitness in the United States.

The American Heart Association issued a Policy Statement in 2013 that characterized the importance of cardiorespiratory fitness (CRF) as an essential marker of health outcomes and specifically the need for increased assessment of CRF. This statement summarized the evidence demonstrating that CRF is "one of the most important correlates of overall health status and a potent predictor of an individual's future risk of cardiovascular disease." Subsequently, this Policy Statement led to the development of a National Registry for CRF (Fitness Registry and the Importance of Exercise: A National Data Base [FRIEND]) which established normative reference values for CRF for adults in the United States (US). This review provides an overview of the progress made in the past decade to further our understanding of the importance of CRF, specifically related to prevention and for clinical populations. Additionally, this review overviews the evolvement and additional uses of FRIEND and summarizes a hierarchy of assessment methods for CRF. In summary, continued efforts are needed to expand the representation of data from across the US, and to include data from pediatric populations, to further develop the CRF Reference Standards for the US as well as further develop Global CRF Reference Standards.

Stroke Incidence in Patients With Hypertension According to Cardiorespiratory Fitness.

BACKGROUND: Hypertension and physical inactivity are risk factors for stroke. The effect of cardiorespiratory fitness (CRF) on stroke risk in patients with hypertension has not been assessed. We evaluated stroke incidence in patients with hypertension according to CRF and changes in CRF. METHODS: We included 483 379 patients with hypertension (mean age±SD; 59.4±9.0 years) and no evidence of unstable cardiovascular disease as indicated by a standardized exercise treadmill test. Patients were assigned to 5 age- and sex-specific CRF categories based on peak metabolic equivalents achieved at the initial exercise treadmill test and in 4 categories based on metabolic equivalent changes over time (n=110 576). Multivariable Cox models, adjusted for age, and comorbidities were used to estimate hazard ratios and 95% CIs for stroke risk. RESULTS: During a median follow-up of 10.6 (interquartile range, 6.6-14.6) years, 15 925 patients developed stroke with an average yearly rate of 3.1 events/1000 person-years. Stroke risk declined progressively with higher CRF and was 55% lower for the High-fit individuals (hazard ratio, 0.45 [95% CI, 0.42-0.48]) compared with the Least-fit. Similar associations were observed across the race, sex, and age spectra. Poor CRF was the strongest predictor of stroke risk of all comorbidities studied (hazard ratio, 2.24 [95% CI, 2.10-2.40]). Changes in CRF reflected inverse and proportional changes in stroke risk. CONCLUSIONS: Poor CRF carried a greater risk than any of the cardiac risk factors in patients with hypertension, regardless of age, race, or sex. The lower stroke risk associated with improved CRF suggests that increasing physical activity, even later in life, may reduce stroke risk.

Temporal Trends in Cardiac Rehabilitation Participation and Its Core Components: A Nationwide Cohort Study From the Netherlands.

PURPOSE: Patient- and disease-specific data on cardiac rehabilitation (CR) participation and changes over time are limited. The objective of this study was to describe time trends in CR participation between 2013 and 2019 and provides insights into the utilization of CR components. METHODS: Patients with cardiovascular disease (CVD) with an indication for CR were enrolled between 2013 and 2019. Dutch health insurance claims data were used to identify CR participation and its components. RESULTS: In total, 106 212 patients with CVD were included of which 37% participated in CR. Participation significantly increased from 28% in 2013 to 41% in 2016 but remained unchanged thereafter. Participation was highest in the youngest age groups (<50 yrs 52%; 50-65 yrs 50%), men (48%), patients with ST-segment elevation myocardial infarction (73%), non-ST-segment elevation myocardial infarction (59%), and coronary artery bypass grafting (82%). In contrast, it was the lowest in the oldest age group (≥85 yrs 8%), women (30%), and in patients with heart failure (11%). Most participants in CR received referral plus an admission session (97%) and exercise training (82%), whereas complementary services related to dietary (14%) and mental health counseling (10%) had a low utilization. CONCLUSIONS: CR participation rates increased to 41% in 2016 but remained unchanged thereafter. Participation modulators included age, sex, CVD diagnosis, and undergoing a cardiothoracic procedure. Education and exercise sessions were frequently adopted, but dietary and mental health counseling had a low utilization rate. These findings suggest the need for reinvigorated referral and novel enrollment strategies in specific CVD subgroups to further promote CR participation and its associated underutilized adjunctive services.

Injury or activity-related pain sustained by a population of at-risk women during a 6-month exercise program.

BACKGROUND: Exercise provides numerous cardiovascular (CV) benefits to women; however, identifying women who are likely to sustain musculoskeletal injury or discomfort is important when tailoring exercise activities. PURPOSE: To evaluate factors associated with the incidence of injury in women at risk for CV disease (CVD) during their participation in a structured exercise intervention for primary CVD prevention. STUDY DESIGN: Retrospective comparative study. METHODS: Baseline anthropometric measures, CV efficiency (via standardized submaximal treadmill testing), and questionnaire-based assessments of functional capacity (Duke Activity Status Index [DASI]), daytime sleepiness (Epworth Sleepiness Scale), and depression (9-item Patient Health Questionnaire) were compared between participants sustaining an injury or experiencing persistent pain, regardless of cause, with those reporting no such events. RESULTS: Of 117 women enrolled in the study, 27 (23%) experienced an injury or activity-related musculoskeletal pain during the program (injured group). Baseline characteristics for the entire group were: age, 57.3 years; weight, 203 lb; body mass index, 34.8 kg/m 2 ; and waist circumference, 39.9 in. Characteristics did not differ significantly between the injured and non-injured groups for baseline demographics (P > 0.05), but obesity incidence (body mass index ≥ 30 kg/m 2 ) was more prevalent in the injured group (P = 0.02). On univariate analysis, 9-item Patient Health Questionnaire depression scores were higher for injured participants (5.6 vs 4.1, P = 0.16) and DASI activity scores were significantly lower for injured participants (31.3 vs 41.0, P = 0.004) despite there being no significant difference in baseline exercise capacity, expressed as metabolic equivalents (8.1 vs 7.5, P = 0.20) between groups. The DASI score was an independent predictor of injury by multivariate analysis (P = 0.0092). CONCLUSION: Women study participants who were injured or experienced activity-related pain during a 6-month structured exercise intervention (injured group) had similar waist measurements, lipid/lipoprotein level profiles, and hemodynamic responses compared with women study participants who were event free (non-injured group); however, injured-group participants were more obese, more depressed, and reported lower functional capacity. Women who have the characteristics of the injured-group participants may be at greater risk for activity-induced injury when participating in exercise-based prevention programs for CV health.

Energy expenditure, cardiorespiratory, and perceptual responses to shallow-water aquatic exercise in young adult women.

INTRODUCTION: Aquatic exercise (AE) is a popular form of physical activity, yet few studies have assessed the individual's energy expenditure (EE) associated with a continuous bout of AE. Studies using indirect calorimetry to measure EE have reported limitations associated with test methodology and the ability to control individual's exercise intensity or tempo. PURPOSE: To evaluate EE and cardiorespiratory (CR) responses during a 40-minute shallow-water AE session in young adult women. METHODS: Twenty-one healthy women (aged 21.7 ± 3.4 years) completed an orientation practice session and a 40-minute shallow-water AE session using a traditional exercise class format and the SWEAT video-based instructional cuing program. The high-intensity interval format included the following segments: 1) warm-up (3 minutes); 2) CR segment ( 22 minutes); 3) muscular endurance segment (ME; 10 minutes); and 4) cool-down (5 minutes). Subject oxygen consumption (VO2; mL/kg/min), heart rate (HR) and OMNI overall ratings of perceived exertion (RPE-O) were assessed each minute. Average kcal/min1, metabolic equivalents (METs; 1 MET = 3.5 mL/kg/min), and total kcals per segment and for the overall session were calculated. RESULTS: The total subject EE throughout the 40-minute trial (including warm-up and cool-down segments) was 264 kcals, with an overall average of 6.3 kcals/min (5.6 METs).The average kcals/min expended throughout CR segments 2 through 6 was 8.05 (7.1 METs), with the Hoverjog segment producing the greatest average kcals/min at 8.3 (7.3 METs). The CR portion (22 min) contributed 65% of the total EE (171 kcals) of the 40-minute AE trial. For the overall AE trial, the highest and average subject VO2 achieved were 33.3 and 19.7 mL/kg/min, respectively. The average highest subject heart rate achieved was 177 beats per minute (bpm), equivalent to 90% of the participant's age-predicted HRmax. CONCLUSION: Energy expenditure during a 40-minute AE session met national recommendations for a daily moderate-to-vigorous bout of physical activity offering a viable alternative to land-based exercise. Because AE serves as a partial-weight bearing modality, future studies are needed to clarify the EE of shallow-water AE in apparently healthy and clinical populations.