Sandra Mandic

Addition of the electrocardiogram to the preparticipation examination of college athletes.

Objective: Although the use of standardized cardiovascular (CV) system-focused history and physical examination is recommended for the preparticipation examination (PPE) of athletes, the addition of the electrocardiogram (ECG) has been controversial. Because the impact of ECG screening on college athletes has rarely been reported, we analyzed the findings of adding the ECG to the PPE of Stanford athletes. Design: For the past 15 years, the Stanford Sports Medicine program has mandated a PPE questionnaire and physical examination by Stanford physicians for participation in intercollegiate athletics. In 2007, computerized ECGs with digital measurements were recorded on athletes and entered into a database. Setting: Although the use of standardized CV-focused history and physical examination are recommended for the PPE of athletes, the addition of the ECG has been controversial. Because the feasibility and outcomes of ECG screening on college athletes have rarely been reported, we present findings derived from the addition of the ECG to the PPE of Stanford athletes. For the past 15 years, the Stanford Sports Medicine program has mandated a PPE questionnaire and physical examination by Stanford physicians for participation in intercollegiate athletics. In 2007, computerized ECGs with digital measurements were recorded on athletes and entered into a database. Main Outcome Measures: Six hundred fifty-eight recordings were obtained (54% men, 10% African-American, mean age 20 years) representing 24 sports. Although 68% of the women had normal ECGs, only 38% of the men did so. Incomplete right bundle branch block (RBBB) (13%), right axis deviation (RAD) (10%), and atrial abnormalities (3%) were the 3 most common minor abnormalities. Sokolow-Lyon criteria for left ventricular hypertrophy (LVH) were found in 49%; however, only 27% had a Romhilt-Estes score of ≥4. T-wave inversion in V2 to V3 occurred in 7%, and only 5 men had abnormal Q-waves. Sixty-three athletes (10%) were judged to have distinctly abnormal ECG findings possibly associated with conditions including hypertrophic cardiomyopathy or arrhythmogenic right ventricular dysplasia/cardiomyopathy. These athletes were offered further testing but this was not mandated according to the research protocol. Results: Six hundred fifty-three recordings were obtained (54% men, 7% African American, mean age 20 years), representing 24 sports. Although 68% of the women had normal ECGs, only 38% of the men did so. Incomplete RBBB (13%), RAD (10%), and atrial abnormalities (3%) were the 3 most common minor abnormalities. Sokolow-Lyon criteria for LVH were found in 49%; however, only 27% had a Romhilt-Estes score of ≥4. T-wave inversion in V2 to V3 occurred in 7% and only 5 men had abnormal Q-waves. Sixty-five athletes (10%) were judged to have distinctly abnormal ECG findings suggestive of arrhythmogenic right ventricular dysplasia, hypertrophic cardiomyopathy, and/or biventricular hypertrophy. These athletes will be submitted to further testing. Conclusions: Mass ECG screening is achievable within the collegiate setting by using volunteers when the appropriate equipment is available. However, the rate of secondary testing suggests the need for an evaluation of cost-effectiveness for mass screening and the development of new athlete-specific ECG interpretation algorithms.

Resistance training and cardiac hypertrophy: Unravelling the training effect

AbstractResistance training (RT) is a popular method of conditioning to enhance sport performance aswell as an effective form of exercise to attenuate the age-mediated decline in muscle strength and mass. Although the benefits of RT on skeletal muscle morphology and function are well established, its effect on left ventricular (LV) morphology remains equivocal. Some investigations have found that RT is associated with an obligatory increase in LV wall thickness and mass with minimal alteration in LV internal cavity dimension, an effect called concentric hypertrophy. However, others report that short- (<5 years) to long-term (>18 years) RT does not alter LV morphology, arguing that concentric hypertrophy is not an obligatory adaptation secondary to this form of exertion. This disparity between studies on whether RT consistently results in cardiac hypertrophy could be caused by: (i) acute cardiopulmonary mechanisms that minimise the increase in transmural pressure (i.e. ventricular pressure minus intrathoracic pressure) and LV wall stress during exercise; (ii) the underlying use of anabolic steroids by the athletes; or (iii) the specific type of RT performed. We propose that when LV geometry is altered after RT, the pattern is usually concentric hypertrophy in Olympic weightlifters. However, the pattern of eccentric hypertrophy (increased LV mass secondary to an increase in diastolic internal cavity dimension and wall thickness) is not uncommon in bodybuilders. Of particular interest, nearly 40% of all RT athletes have normal LV geometry, and these athletes are typically powerlifters. RT athletes who use anabolic steroids have been shown to have significantly higher LV mass compared with drug-free sport-matched athletes. This brief review will sort out some of the factors that may affect the acute and chronic outcome of RT on LV morphology. In addition, a conceptual framework is offered to help explain why cardiac hypertrophy is not always found in RT athletes.

Effects of aerobic or aerobic and resistance training on cardiorespiratory and skeletal muscle function in heart failure: a randomized controlled pilot trial

Objective: To examined the effects of different training modalities on exercise capacity (Vo 2peak), systolic function, muscular strength and endurance and quality of life in heart failure patients. Design: Randomized controlled trial. Setting: Cardiac rehabilitation centre in Canada. Subjects: Forty-two individuals with heart failure (62 ± 12 years; New York Heart Association (NYHA) classes I—III). Interventions: Aerobic training (n = 14), combined aerobic and resistance training (n = 15) or usual care (n = 13) three times per week for 12 weeks. Main measures: (1) Vo 2peak measured by symptom-limited graded exercise test on cycle ergometer; (2) systolic function assessed by two-dimensional echocardiography; (3) muscular strength and muscular endurance measured by one-repetition maximum procedure; and (4) quality of life assessed by questionnaires. Results: In the intention-to-treat analysis, neither aerobic nor combined aerobic and resistance training significantly improved Vo2peak, systolic function or quality of life compared with usual care. However, combined aerobic and resistance training significantly improved upper extremity strength (40.7 (14.0)—48.5 (16.0) kg, P<0.05) and muscular endurance (5.7 (2.7)—11.6 (7.6) reps, P<0.05) compared with aerobic training or usual care. In compliant participants (exercise adherence 80%), Vo2peak increased in the aerobic group (16.9 (6.0)—19.0 (6.8), P= 0.026) and tended to increase in the combined training group (15.9 (5.0)—17.6 (5.6), P= 0.058) compared with usual care. Quality of life was improved in the aerobic group only. Conclusions: Both aerobic and combined aerobic and resistance training are effective interventions to improve Vo2peak in compliant heart failure patients. Combined training may be more effective in improving muscle strength and endurance.

Maximal exercise oxygen pulse as a predictor of mortality among male veterans referred for exercise testing

Background Maximal oxygen pulse (O2 pulse) mirrors the stroke volume response to exercise, and should therefore be a strong predictor of mortality. Limited and conflicting data are, however, available on this issue. Methods Nine hundred forty-eight participants, classified as those with cardiopulmonary disease (CPD) and those without (non-CPD), underwent cardiopulmonary exercise testing (CPX) for clinical reasons between 1993 and 2003. The ability of maximal O2 pulse and maximal oxygen uptake (peak VO2) to predict mortality was investigated using proportional hazards and Akaike information criterion analyses. All-cause mortality was the endpoint. Results Over a mean follow-up of 6.3 ± 3.2 years, there were 126 deaths. Maximal O2 pulse, expressed in either absolute or relative to age-predicted terms, and peak VO2 were significant and independent predictors of mortality in those with and without CPD (P < 0.04). Akaike information criterion analysis revealed that the model including both maximal O2 pulse and peak VO2 had the highest accuracy for predicting mortality. The optimal cut-points for O2 pulse and peak VO2 (< 12; ≥ 12 ml/beat and < 16; ≥ 16 ml/(kg · min) respectively) were established by the area under the receiver-operating-characteristic curve. The relative risks of mortality were 3.4 and 2.2 (CPD and non-CPD, respectively) among participants with both maximal O2 pulse and peak VO2 responses below these cut-points compared with participants with both responses above these cut-points. Conclusion These results indicate that maximal O2 pulse is a significant predictor of mortality in patients with and without CPD. The addition of absolute and relative O2 pulse data provides complementary information for risk-stratifying heterogeneous participants referred for CPX and should be routinely included in the CPX report.

Resistance Versus Aerobic Exercise Training in Chronic Heart Failure

It is now accepted that exercise training is a safe and effective therapeutic intervention to improve clinical status, functional capacity, and quality of life in people with chronic heart failure (CHF). Nevertheless, this therapeutic modality remains underprescribed and underutilized. Both aerobic and resistance training improve exercise capacity and may partially reverse some of the cardiac, vascular, and skeletal muscle abnormalities in individuals with CHF. Aerobic training has more beneficial effects on aerobic power (peak oxygen consumption) and cardiac structure and function than resistance exercise training, while the latter is more effective for increasing muscle strength and endurance and promoting favorable arterial remodeling. Combined aerobic and resistance training is the preferred exercise intervention to reverse or attenuate the loss of muscle mass and improve exercise and functional capacity, muscle strength, and quality of life in individuals with CHF. The challenge now is to translate these research findings into clinical practice.

Cardiovascular adaptations to exercise training in postmenopausal women with type 2 diabetes mellitus

BackgroundType 2 diabetes mellitus (DM-2) is one of the most prevalent chronic diseases of the aged and contributes to a significant amount of cardiovascular disease morbidity and mortality. Exercise training may be beneficial in attenuating the cardiovascular maladaptations associated with DM-2. The purpose of this study was to examine the effects of exercise training on left ventricular (LV) and vascular function in a sample of postmenopausal women with DM-2.MethodsTwenty-eight postmenopausal women with DM-2 (age: 59 ± 7 yrs) were assigned to either an exercise training (ET) (n = 17) or control group (CT) (n = 7). Cardiorespiratory fitness (), LV filling dynamics and arterial compliance were assessed at baseline in all participants. The ET group performed a supervised aerobic and resistance training intervention three days per week for a period of 10 weeks, while the CT group continued normal activities of daily living.ResultsBody mass index, , age and duration of diabetes were similar between the ET and CT groups at baseline. (21.3 ± 3.3 to 24.5 ± 4.2 ml·kg-1·min-1, p < 0.05) and large artery compliance (1.0 ± 0.4 to 1.2 ± 0.4 mL·mmHg-1, p < 0.05), increased significantly in the ET group following training despite no change in LV filling dynamics, blood pressure, lipid profile or insulin sensitivity. All variables remained unchanged in the CT group.ConclusionsExercise training improves large artery compliance and cardiorespiratory fitness in postmenopausal women with DM-2, without any appreciable changes in LV filling dynamics or conventional risk factors for cardiovascular disease.

Personal, social and environmental correlates of active transport to school among adolescents in Otago, New Zealand.

OBJECTIVES With increasingly sedentary lifestyles, opportunities for physical activity such as active transport to school need to be promoted in adolescents. This study examines personal, social and environmental correlates of active transport to school among adolescents including sociodemographics, behavioural patterns, motivational factors, perceived barriers, peer support, family resources, school characteristics, urban/rural setting, distance to school and neighbourhood safety perceptions. DESIGN Cross-sectional study. METHODS In 2009 and 2011, 2018 secondary school students (age: 14.8±1.3 years; 73% urban; 53% boys) from 22 out of 24 schools from Otago, New Zealand completed the Otago School Students Lifestyle Survey. Multivariate binary logistic regression models were used to compare active transport to school correlates in students using active transport to school versus bus and car users (motorised transport). RESULTS Overall, 37% of students used active transport to school, 24% bus, and 39% car. Compared to motorised transport users, active transport to school users were more likely to live closer to school (1.4±1.4 active transport to school vs. 8.3±8.4km motorised transport; p<0.001). In a multivariate analysis, shorter distance to school (OR (95%CI) (0.03 (0.01-0.05)), younger age (0.85 (0.78-0.92)), fewer vehicles (0.66 (0.49-0.89)) and fewer screens (0.53 (0.35-0.82)) per household, meeting screen time guidelines (1.74 (1.22-2.50)), opportunity to chat with friends (2.26 (1.58-3.23)), nice scenery (1.69 (1.14-2.50)), and parental perceptions of active transport to school safety (2.32 (1.25-4.30)) were positively associated with active transport to school, while perceived time constraints (0.46 (0.29-0.72)) and attending girls-only school (0.51 (0.35-0.75)) had a negative association with active transport to school. CONCLUSIONS Future active transport to school interventions in adolescents should focus on encouraging active transport to school, reiterating its social benefits, and addressing parental safety concerns around active transport to school.

The role of exercise in the treatment of cardiovascular disease associated with type 2 diabetes mellitus

The role of exercise training in the prevention and treatment of type 2 diabetes mellitus has been studied extensively over the past two decades. Although the primary treatment aim for patients with type 2 diabetes is metabolic control, the morbidity and mortality associated with the disease is more a function of cardiovascular disease. As exercise is associated with favourable reductions in the risk for cardiovascular disease in other high-risk populations, here we explore the role of exercise in the treatment of cardiovascular maladaptations associated with type 2 diabetes.The cardiovascular adaptation to type 2 diabetes is characterised by hypertrophy, stiffening and loss of functional reserve. Clinically, the cardiovascular adaptations to the diabetic state are associated with an increased risk for cardiovascular disease. Functionally, these adaptations have been shown to contribute to a reduced exercise capacity, which may explain the reduced cardiovascular fitness observed in this population.Exercise training is associated with improved exercise capacity in various populations, including type 2 diabetes. Several structural and functional adaptations within the cardiovascular system following exercise training could explain these findings, such as reductions in ventricular and vascular structural hypertrophy and compliance coupled with increased functional reserve. Although these cardiovascular adaptations to aerobic exercise training have been well documented in older populations with similar decrements in cardiovascular fitness and function, they have yet to be examined in patients with type 2 diabetes. For this reason, we contend that exercise training may be an excellent therapeutic adjunct in the treatment of diabetic cardiovascular disease.

Getting kids active by participating in sport and doing It more often: focusing on what matters

BackgroundReduced time dedicated to physical education and free play in recent decades emphasizes the need to promote opportunities for sport participation in adolescents in order to increase physical activity levels. The purpose of this study was to examine the association of sociodemographic and biological characteristics, behavioural patterns, and school-related and sport-specific variables with time spent participating in sport.MethodsA total of 1837 secondary school students (age: 14.6 ± 1.2 years; 50.9 % boys) from 19 of 23 schools in the Otago Region (New Zealand) completed an online sport survey and Youth Physical Activity Questionnaire in 2009. Using multilevel modeling, we examined the association of individual-, school- and sport-related variables on sport participation and the amount of time spent in sports.ResultsHigher rates of sport participation were associated with lower neighbourhood deprivation scores (OR (95%CI): 0.75 (0.49-1.14), 0.57 (0.38-0.86), 0.48 (0.28-0.81)), higher quintiles of physical activity (2.89 (2.10-3.96), 2.81 (1.68-4.70), 3.54 (2.24-5.57), 3.97 (1.99-7.95)), highest quintiles of screen time (1.58 (0.94-2.65), 1.99 (1.42-2.80), 2.17 (1.43-3.30), 1.88 (1.37-2.57)) and boys only school status (2.21 (1.57-3.10)). Greater amount of time spent in sports was associated with male gender (0.56 (0.43-0.74), lower neighbourhood deprivation scores (0.72 (0.59-0.93), 0.78 (0.58-1.04), 0.62 (0.39-1.00)), higher quintiles of physical activity (3.18 (2.29-4.41), 4.25 (2.91-6.20), 8.33 (5.58-12.44), 6.58 (4.07-10.64)), highest quintile of screen time (1.83 (1.31-2.56), greater availability of sports outside school (1.68 (1.22-2.32)), better sport management (2.57 (1.63-4.07)) and provision of sport courts at school (0.57 (0.40-0.81)). Conversely, obesity was associated with less time spent participating in sport (0.50 (0.31-0.80)).ConclusionResults support the use of sport participation as an effective strategy to increase physical activity levels and identify target groups and areas for interventions, program design and policy development. Interventions should focus on improving accessibility to sport programs for all adolescents, providing adequate sport grounds at school, and promoting good sport management practices. Programs and policies encouraging sport participation should address in particular the needs of adolescents living in deprived neighborhoods, those attending coeducational and girls-only schools, and those who are obese.

Characterizing differences in mortality at the low end of the fitness spectrum in individuals with cardiovascular disease.

Background A graded but nonlinear relationship exists between fitness and mortality, with the greatest mortality differences occurring between the least-fit (first, Q1) and the next-least-fit (second, Q2) quintiles of fitness. The purpose of this study was to compare clinical characteristics, exercise test responses, and physical activity (PA) patterns in Q1 versus Q2 in patients with cardiovascular disease (CVD). Design Observational retrospective study. Methods A total of 5101 patients with a history of CVD underwent clinical treadmill testing and were followed up for 9.1 ± 5.5 years. Patients were classified into quintiles of exercise capacity measured in metabolic equivalents. Clinical characteristics, treadmill test results, and recreational PA patterns were compared between Q1 (n = 923) and Q2 (n = 929). Results Q1 had a nearly two-fold increase in age-adjusted relative risk of cardiovascular mortality compared with Q2 (hazard ratio: 3.79 vs. 2.04, P < 0.05; reference: fittest quintile). Q1 patients were older, had more extensive use of medications, and were more likely to have a history of typical angina (35 vs. 28%), myocardial infarction (30 vs. 24%), chronic heart failure (25 vs. 14%), claudication (15 vs. 9%) and stroke (9 vs. 6%) compared with Q2 (all comparisons: P < 0.05). Recent and lifetime recreational PA was not different between the two groups. Conclusion Greater severity of disease in the least-fit versus the next-least-fit quintile likely contributes to but cannot fully explain marked differences in mortality rates in CVD patients. To achieve potential survival benefits, our results suggest that unfit CVD patients should engage in exercise programs of sufficient volume and intensity to improve fitness. Eur J Cardiovasc Prev Rehabil 17:289-295