Although the observed progress in the cardiovascular disease treatment, the incidence of new and recurrent coronary artery disease remains elevated and constitutes the leading cause of death in the developed countries. Three-quarters of deaths due to cardiovascular diseases could be prevented with adequate changes in lifestyle, including increased daily physical activity. New evidence confirms that there is an inverse dose-response relationship between physical activity and cardiovascular disease and mortality risk. However, participation in moderate to vigorous physical activity may not fully attenuate the independent effect of sedentary activities on increased risk for cardiovascular diseases. Physical activity also plays an important role in secondary prevention of cardiovascular diseases by reducing the impact of the disease, slowing its progress and preventing recurrence. Nonetheless, most of eligible cardiovascular patients still do not benefit from secondary prevention/cardiac rehabilitation programs. The present review draws attention to the importance of physical activity in the primary and secondary prevention of cardiovascular diseases. It also addresses the mechanisms by which physical activity and regular exercise can improve cardiovascular health and reduce the burden of the disease.

We assessed the agreement between maximal oxygen consumption (VO2max) measured directly when performing the 20-m shuttle run test and estimated VO2max from five different equations (i.e., Barnett, equations a and b; Leger; Matsuzaka; and Ruiz) in youths. The 20-m shuttle run test was performed by 26 girls (mean age 14.6 years, s = 1.5; body mass 57.2 kg, s = 8.9; height 1.60 m, s = 0.06) and 22 boys (age 15.0 years, s = 1.6; body mass 63.5 kg, s = 11.5; height 1.70 m, s = 0.01). The participants wore a portable gas analyser (K4b2, Cosmed) to measure VO2max during the test. All the equations significantly underestimated directly measured VO2max, except Barnett's (b) equation. The mean difference ranged from 1.3 ml x kg(-1) x min(-1) (Barnett (b)) to 5.5 ml x kg(-1) x min(-1) (Leger). The standard error of the estimate ranged from 5.3 ml x kg(-1) x min(-1) (Ruiz) to 6.5 ml x kg(-1) x min(-1) (Leger), and the percentage error ranged from 21.2% (Ruiz) to 38.3% (Léger). The accuracy of the equations available to estimate VO2max from the 20-m shuttle run test is questionable at the individual level. Furthermore, special attention should be paid when comparisons are made between studies (e.g., population-based studies) using different equations. The results of the present study suggest that Barnett's (b) equation provides the closest agreement with directly measured VO2max (cardiorespiratory fitness) in youth.

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This review aimed to examine the effects of exercise training on mobilization of endothelial progenitor cells (EPCs) in patients with cardiovascular disease and to discuss the possible mechanisms involved in the process. A computer-aided search on PubMed and PEDro was conducted to identify relevant studies published up to June 2012. Two reviewers independently selected studies for inclusion and extracted data, namely, quantitative assessment of circulating EPCs. Of the 88 identified studies, 13 met the inclusion criteria. The 13 studies enrolled 648 participants, including patients with chronic heart failure, peripheral artery disease, and coronary artery disease. The exercise characteristics varied largely across the studies: exercise duration ranged from 2 wks to 6 mos, session duration ranged from 20 to 60 mins, and exercise intensity was usually calculated using the maximal heart rate (ranging from 75% to 85%) or the peak/maximum oxygen consumption (60%-70%). All studies used aerobic exercise. The great majority of the 13 studies reported significant effects of different exercise regimens on the number of circulating EPCs. In summary, exercise training seems to increase the number of circulating EPCs, which could contribute to vascular regeneration and angiogenesis. These positive effects of chronic exercise seem to be closely related to the bioavailability of nitric oxide, including increased activity of endothelial nitric oxide synthase and antioxidant enzymes, and activation of matrix metalloproteinase 9.

This study aimed to investigate the effects of training on health-related quality of life (HRQoL), body composition, and function in older adults. Fifty participants were randomized into aerobic training (AT—70%-80% HRreserve), resistance training (RT—80% 1RM), or controls. They had HRQoL, body composition, and function assessed before and after 8 months. Training groups reduced body fat, increased performance in the stair ascent, 8-ft up-and-go and sit-to-stand five-times tests, and improved their physical component score (PCS; p ≤ .03). AT increased performance in the 6MWT test, and improved general and mental health (MH) domains when compared to controls (p < .01). Finally, changes in stair ascent were associated with changes in bodily pain, MH, and mental component score (p ≤ .04), while changes in handgrip strength were associated with changes in physical role and MH (p = .03). AT and RT were effective interventions for decreasing body fat and improving functionality and the PCS in older adults.

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Studies that aim to characterize oxygen uptake kinetics in efforts above maximal oxygen consumption intensity are scarce. Our aim was to analyze the oxygen kinetics in a maximal 200-m front crawl, all measurements being conducted in swimming pool conditions. 10 high-level male swimmers performed a maximal 200-m bout and oxygen uptake was directly measured through breath-by-breath gas analysis. Mean (±SD) peak oxygen uptake was 68.58 (±5.79) ml.kg(-1).min(-1), evidencing a fast component phase. As expected, peak oxygen uptake presented a direct relationship with mean swimming speed of the first 50-m lap and with the 200-m effort, and was also correlated with the amplitude of the fast component (r=0.75, r=0.72, r=0.73, p<0.05, respectively). The observed mean amplitude value was higher than those observed in the literature for other exercise intensity domains. However, the time for its onset, as well as the duration for attaining the steady state, was shorter, as the peak oxygen uptake was not correlated with these 2 components. Moreover, as previously described for swimming at high intensities, the slow component phenomenon was not observed. Aerobic metabolic pathway accounted for 78.6%, confirming the high aerobic contribution in middle distance swimming events.

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