BACKGROUND\nIncreased physical activity is related to reduced risk of cardiovascular disease, possibly because it leads to improvement in the lipoprotein profile. However, the amount of exercise training required for optimal benefit is unknown. In a prospective, randomized study, we investigated the effects of the amount and intensity of exercise on lipoproteins.\n\n\nMETHODS\nA total of 111 sedentary, overweight men and women with mild-to-moderate dyslipidemia were randomly assigned to participate for six months in a control group or for approximately eight months in one of three exercise groups: high-amount-high-intensity exercise, the caloric equivalent of jogging 20 mi (32.0 km) per week at 65 to 80 percent of peak oxygen consumption; low-amount-high-intensity exercise, the equivalent of jogging 12 mi (19.2 km) per week at 65 to 80 percent of peak oxygen consumption; or low-amount-moderate-intensity exercise, the equivalent of walking 12 mi per week at 40 to 55 percent of peak oxygen consumption. Subjects were encouraged to maintain their base-line body weight. The 84 subjects who complied with these guidelines served as the basis for the main analysis. Detailed lipoprotein profiling was performed by nuclear magnetic resonance spectroscopy with verification by measurement of cholesterol in lipoprotein subfractions.\n\n\nRESULTS\nThere was a beneficial effect of exercise on a variety of lipid and lipoprotein variables, seen most clearly with the high amount of high-intensity exercise. The high amount of exercise resulted in greater improvements than did the lower amounts of exercise (in 10 of 11 lipoprotein variables) and was always superior to the control condition (11 of 11 variables). Both lower-amount exercise groups always had better responses than the control group (22 of 22 comparisons).\n\n\nCONCLUSIONS\nThe highest amount of weekly exercise, with minimal weight change, had widespread beneficial effects on the lipoprotein profile. The improvements were related to the amount of activity and not to the intensity of exercise or improvement in fitness.

Effects of the amount and intensity of exercise on plasma lipoproteins: Editor's comments

Natural History, Diagnostic Approaches, and Therapeutic Strategies for Patients With Asymptomatic Severe Aortic Stenosis.

The management strategy in asymptomatic patients with severe aortic stenosis (AS) is controversial. Aortic valve replacement has significant morbidity and mortality, while there is a risk for sudden cardiac death with conservative management. There is no consensus on the prognostic value of stress testing to stratify management. A pooled analysis of studies in patients with severe AS was performed to assess the prognostic value of stress testing for adverse events, including angina, dyspnea, acute heart failure, sudden death, and symptoms requiring aortic valve replacement. A search of published research was performed using the terms "stress test" and "asymptomatic aortic stenosis." A random-effects model was used to calculate pooled odds ratios and 95% confidence intervals. Data from 7 studies were included (491 patients with asymptomatic severe AS). None of the patients experienced any complications during or after stress testing. There were no sudden deaths in the patients with normal stress test results after 1 year of follow-up, while 5% with abnormal stress test results had sudden cardiac death. Overall, 52 of 253 patients (21%) with normal stress test results had adverse cardiac events, compared with 156 of 238 (66%) with abnormal stress test results (odds ratio 0.12, 95% confidence interval 0.07 to 0.21, p <0.001). In conclusion, stress testing in asymptomatic patients with severe AS is safe and identifies patients at risk for adverse cardiac events and sudden cardiac death. These data suggest that stress tests can be used for risk stratification and for deciding on the timing of aortic valve replacement in asymptomatic patients with severe AS.

Meta-analysis of prognostic value of stress testing in patients with asymptomatic severe aortic stenosis.

Aim Patients with asymptomatic aortic stenosis (AS) and abnormal haemodynamic responses to exercise testing are at increased risk of cardiac events. This study assesses the Doppler echocardiographic determinants of a positive exercise test in a cohort of asymptomatic patients with AS. Methods and results One hundred and twenty-eight patients with AS underwent quantitative Doppler echocardiographic measurements at rest and during exercise test. Of these patients, 60 had an abnormal response to exercise. Two independent determinants of an abnormal exercise response were selected in multivariate analysis: a larger increase in mean transaortic pressure gradient (P ¼ 0.00014) and a limited contractile reserve—latent left ventricular dysfunction—as indicated by smaller changes in ejection fraction (P ¼ 0.0002). Limiting symptoms were associated with greater increase in mean transaortic pressure gradient, smaller changes in systolic blood pressure and a lower ejection fraction at peak exercise. The increase in pressure gradient was associated with smaller exercise-induced changes in aortic valve area and in ejection fraction and new or worsening mitral regurgitation during exercise. Conclusion Abnormal responses to exercise in asymptomatic AS patients are mediated by a larger increase in mean transaortic pressure gradient and/or a limited contractile reserve characterized by an inadequate increase in ejection fraction at exercise.

Determinants of an abnormal response to exercise in patients with asymptomatic valvular aortic stenosis.

Background
The athlete’s heart is associated with physiological remodeling as a consequence of repetitive cardiac loading. The effect of exercise training on left ventricular (LV) cardiac strain and twist mechanics are equivocal, and no meta-analysis has been conducted to date.

https://link.springer.com/content/pdf/10.1007%2Fs40279-016-0644-4.pdf

Left Ventricular Speckle Tracking-Derived Cardiac Strain and Cardiac Twist Mechanics in Athletes: A Systematic Review and Meta-Analysis of Controlled Studies

Aims: To determine the safety of exercise testing (ET) in patients with moderate or severe asymptomatic aortic stenosis (AAS) and its accuracy to predict the need for surgery and mo

Exercise testing in asymptomatic aortic stenosis.

Introduccion y objetivos. Los cambios estructurales y funcionales existentes en el ventriculo izquierdo (VI) de futbolistas profesionales podrian determinar cambios en el movimiento de rotacion ventricular (Rv) y torsion ventricular (Tv). El objetivo fue caracterizar los cambios en la Tv existentes en futbolistas profesionales. Metodos. A 17 futbolistas y 10 voluntarios sanos no entrenados (grupo control), se les realizo un estudio ecocardiografico en modos M y B y Doppler. Se cuantificaron parametros estructurales y de funcion sistolica y diastolica del VI. La Rv basal y apical y la Tv se evaluaron utilizando un software disenado para estos fines (EchoPAC, GE Medical Systems). La Tv se caracterizo en el dominio temporal. Resultados. Todos los sujetos presentaron estructura y funcion del VI dentro del rango de normalidad. La fraccion de eyeccion y la de acortamiento fueron mayores en los futbolistas (p < 0,05). Los niveles de Rv apical y basal y los niveles y velocidades de Tv fueron menores en los futbolistas (p < 0,05). En los futbolistas, la Tv maxima alcanzada y la fraccion de eyeccion y la de acortamiento mostraron correlacion negativa (p < 0,05). Conclusiones. Los niveles y las velocidades de TV fueron menores en los futbolistas. Las reducciones en la Tv pueden ocurrir en condiciones fisiologicas y podrian representar una respuesta adaptativa que contribuye a aumentar la eficiencia ventricular.

La reducción en el nivel y la velocidad de la torsión ventricular puede asociarse a incremento en la eficiencia ventricular izquierda: evaluación mediante ecografía speckle-tracking

Resumen es: La aterosclerosis que afecta a los vasos de los miembros inferiores, llevandolos a la amputacion, tambien puede involucrar otros vasos (coronarios, carot...

Rehabilitación cardiovascular en amputados de miembros inferiores de causa vascular

Barometric pressure and partial oxygen pressure decrease with increasing altitude. Hypobaric hypoxia produced is responsible for altitude-related diseases and it can cause severe decrements in exercise performance. The physiological adaptations to the altitude are multiple and they contribute to alter different athletic qualities. The VO2 worsening could be associated to increased pulmonary vascular resistance and nitric oxide diffusion alteration. Performance impairments at altitude can also be accentuated by hypoxia-induced elevations in pulmonary arterial pressure. Clinical studies have demonstrated the beneficial effects of sildenafil on the treatment of pulmonary hypertension. These effects have led to suggest that its indication for competitions at altitude might improve athletic performance. The investigations demonstrate different results depending on the altitude level and times and intensities of exercise. Some studies show performance improvements, although not in all participants. Individual responses vary widely between different athletes. This presentation examines the effects of altitude on exercise capacity and shows studies about the use of sildenafil to improve sport performance. This text also discusses the possible side effects and implications for the use of sildenafil in athletes, indication that is not the basic one of the drug. The physicians must know in each athlete the individual sildenafil side effects that could arise and that would influence negatively on health and performance.

/pdf/sildenafil-and-exercise-performance-at-altitude-4gnqigmrcd.pdf

Sildenafil and exercise performance at altitude

The left ventricle (LV) torsion is an important feature of the ventricle’s biomechanics. Using speckle-tracking echography (STE) the assessment of LV torsion dynamics would be more available in clinical and research cardiology Particular features of the LV torsion have been described during exercise and in some sportsmen, but up to now the LV torsion dynamics has not been studied in soccer players. The aims were to characterize the LV systolic and diastolic torsion dynamic in professional soccer players using STE, and to analyze the main differences in torsion dynamics between soccer players and age-matched non-trained individuals. To this end the LV apical and basal rotation were quantified, and the systolic and diastolic torsion dynamic was characterized using a time and frequency-domain approach. The STE allowed characterizing the LV torsion level in both groups. The LV torsion level was lesser in soccer players than in non-trained individuals. Soccer players showed lesser amplitudes in the low frequency components of the LV torsion Fourier spectrum.

Time and frequency-domain characterization of the left ventricle torsion pattern of professional soccer players using speckle-tracking echocardiography

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