José Oliveira

Physical activity and school recess time: differences between the sexes and the relationship between children's playground physical activity and habitual physical activity.

The aims of this study were: (1) to observe participation in moderate-to-vigorous physical activity (MVPA) during school recess periods; (2) to determine the relative importance of physical activity during recesses to overall daily physical activity; and (3) to examine differences in physical activity between the sexes during unstructured recess periods. The participants were 22 school children (10 boys, 12 girls) aged 8 – 10 years (mean  =  8.9, s  =  0.7) in the third and fourth grades. Daily totals for the physical activity variables were calculated by summing the values for each hour of 14 h of physical activity measurements (08:00 to 22:00 h). Recess times (minutes) were as follows: morning 10:30 to 11:00 h and afternoon 15:30 to 16:00 h. We did not differences between boys and girls in daily total accelerometer counts or the overall time spent in MVPA. However, girls were significantly (P  < 0.05) more involved (38%) in MVPA during recess time than boys (31%). Participation in MVPA during recess contributes significantly more (P  < 0.05) for girls (19%) than boys (15%) to the total amount of physical activity suggested by international health-related physical activity guidelines, while the percentage of time engaged in MVPA during recess time at school accounts for a small amount of the daily MVPA (6% for boys and 8% for girls). The results of this study suggest that school recess time is an important setting to promote MVPA and contributes to daily physical activity in young children, especially in girls.

Is exercise training an effective therapy targeting endothelial dysfunction and vascular wall inflammation

There is an increasing evidence that endothelial dysfunction and vascular wall inflammation are present in all stages of atherosclerosis. Atherosclerosis does not have to necessarily progress to an acute clinical event. Several therapeutic strategies exist, such as exercise training, which mitigates endothelial dysfunction and inflammation. Exercise training consistently improves the nitric oxide bioavailability, and the number of endothelial progenitor cells, and also diminishes the level of inflammatory markers, namely pro-inflammatory cytokines and C-reactive protein. However, the mechanisms by which exercise improves endothelial function in coronary artery disease patients are not fully clarified. Several mechanisms have been proposed to explain the positive effect of exercise on the disease progression. They include the decrease in cytokine production by the adipose tissue, skeletal muscles, endothelial cells, and blood mononuclear cells, and also, the increase in the bioavailability of nitric oxide, antioxidant defences, and regenerative capacity of endothelium. This study aims to provide a critical review of the literature linking exercise, inflammation, and endothelial dysfunction in coronary artery patients, and to discuss the potential mechanisms behind the exercise-training improvement of endothelial function and inflammatory status.

Aging effects on joint proprioception: the role of physical activity in proprioception preservation

Throughout the human life span the functions of several physiological systems dramatically change, including proprioception. Impaired proprioception leads to less accurate detection of body position changes increasing the risk of fall, and to abnormal joint biomechanics during functional activities so, over a period of time, degenerative joint disease may result. Altered neuromuscular control of the lower limb and consequently poor balance resulting from changes in the proprioceptive function could be related to the high incidence of harmful falls that occur in old age subjects. There is evidence of proprioception deterioration with aging. Regular physical activity seems to be a beneficial strategy to preserve proprioception and prevent falls among older subjects. Some studies have demonstrated that the regular physical activity can attenuate age-related decline in proprioception. This paper reviews the evidence of age effects on joint proprioception. We will discuss the possible mechanisms behind these effects and the role of regular physical activity in the attenuation of age-related decline in proprioception.

Genes and elite athletes: a roadmap for future research

Abstract  There is compelling evidence that genetic factors influence several phenotype traits related to physical performance and training response as well as to elite athletic status. Previous case‐control studies showed that ∼20 genetic variants seem to be associated with elite endurance athletic status. The present review aims to introduce novel methodological approaches in the field of sports genetics research, which can be applied in the near future to analyse the genotype profile associated with elite athletic status. These include genotype–phenotype association studies using gene expression analysis, analysis of post‐transcriptional factors, particularly microRNAs, genome‐wide scan linkage or genome‐wide association studies, and novel algorithm approaches, such as ‘genotype scores’. Several gaps in the current body of knowledge have been indentified including, among others: small sample size of most athletic cohorts, lack of corroboration with replication cohorts of different ethnic backgrounds (particularly, made up of non‐Caucasian athletes), the need of research accounting for the potential role of epigenetics in elite athletic performance, and also the need for future models that take into account the association between athletic status and complex gene–gene and gene–environment interactions. Some recommendations are provided to minimize research limitations in the field of sport genetics.

Exercise Training Improves Diastolic Function in Heart Failure Patients

PURPOSE The studys purpose was to analyze the effects of exercise training on exercise tolerance and left ventricular systolic function and structure in heart failure patients with preserved, mild, and moderate to severe reduction of left ventricular ejection fraction (LVEF). METHODS Ninety-eight patients with moderate to severe (n = 34), mild (n = 33), and preserved (n = 31) LVEF were randomly assigned to exercise training plus usual care (n = 65) or usual care alone (n = 33) in a randomization ratio of 2:1. Left ventricular function, left ventricular dimensions, and exercise tolerance were assessed before and after each intervention. RESULTS Exercise tolerance and LVEF increased with exercise training in all patient groups, whereas they remained unchanged after usual care alone. Exercise training increased the mean ratio of early to late mitral inflow velocities (E/A ratio) and decreased deceleration time (DT) of early filling in patients with mild and preserved LVEF. In patients with moderate to severe systolic dysfunction and advanced diastolic dysfunction (DT < 160 ms), exercise training decreased E/A ratio and increased DT, both of which were unchanged after usual care alone. In the remaining patients (DT > 160 ms), exercise training also improved mitral inflow patterns. Exercise training decreased left ventricular dimensions in patients with mild and moderate to severe reduction of LVEF but not in patients with preserved LVEF. CONCLUSIONS These results indicate that exercise training can improve the course of heart failure independent of the degree of baseline left ventricular dysfunction.

Exercise Training-Based Pulmonary Rehabilitation Program Is Clinically Beneficial for Idiopathic Pulmonary Fibrosis

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic, devastating, interstitial lung disease, with few therapeutic options. IPF is characterized by pulmonary restriction, dyspnea, hypoxemia, exercise intolerance and poor quality of life (QOL). Objectives: We aimed to examine the effect of exercise training (ET) on clinical outcomes in IPF patients. Methods: A randomized controlled study included thirty-two IPF patients (aged 68 ± 8 years) who were allocated either to the ET group (n = 15), participating in a 12-week, twice-weekly 60-min supervised ET-based pulmonary rehabilitation program, or to a control group (n = 17) continuing with regular medical treatment alone. Cardiopulmonary exercise test, 6-min walking distance (6MWD) test, 30-second chair-stand test, pulmonary function tests, dyspnea and QOL were assessed at baseline and at the end of the 12-week intervention. Results: Significant differences were observed between the ET and the control groups in raw mean deltas (Δ = post- - pre-intervention): Δ6MWD, 81 m, p < 0.001; ΔVO2 peak, 2.6 ml/kg/min, p = 0.002; Δwork rate, 22 W, p < 0.001; Δanaerobic threshold, 3.1 ml/kg/min, p < 0.001, and ΔFVC % predicted, 6%, p = 0.038. Dyspnea, QOL and 30-second chair-stand were also improved significantly following the program. Conclusions: ET improves exercise tolerance, functional capacity, pulmonary function, dyspnea and QOL in patients with IPF, suggesting a short-term treatment efficacy for clinical improvement, and should be considered the standard care for IPF.

Criterion-related validity of the 20-m shuttle run test in youths aged 13-19 years

Abstract We assessed the agreement between maximal oxygen consumption ([Vdot]O2max) measured directly when performing the 20-m shuttle run test and estimated [Vdot]O2max from five different equations (i.e. Barnett, equations a and b; Léger; 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 [Vdot]O2 during the test. All the equations significantly underestimated directly measured [Vdot]O2max, except Barnetts (b) equation. The mean difference ranged from 1.3 ml · kg−1 · min−1 (Barnett (b)) to 5.5 ml · kg−1 · min−1 (Léger). The standard error of the estimate ranged from 5.3 ml · kg−1 · min−1 (Ruiz) to 6.5 ml · kg−1 · min−1 (Léger), and the percentage error ranged from 21.2% (Ruiz) to 38.3% (Léger). The accuracy of the equations available to estimate [Vdot]O2max 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 Barnetts (b) equation provides the closest agreement with directly measured [Vdot]O2max (cardiorespiratory fitness) in youth.

Effects of a home-based cardiac rehabilitation program on the physical activity levels of patients with coronary artery disease.

PURPOSE Lifestyle changes including daily physical activity (PA) slow the progression of coronary artery disease. This study evaluated the effects of a home-based cardiac rehabilitation education and counseling intervention on daily PA index, daily time spent in different PA intensities, and daily PA patterns. METHODS Thirty patients with history of recent myocardial infarction were recruited and equally divided into intervention (mean age = 67.2 ± 5.4 years) and control (mean age = 69.8 ± 6.14 years) groups. The intervention group received a home-based cardiac rehabilitation intervention program of education and counseling for 12 weeks, regarding cardiovascular risk factor management; benefits and risks of PA; frequency, intensity, duration, and type of PA; moments and activities of daily living to perform PA; effort control procedures during PA; and emergency procedures. During the same period, the control group received usual outpatient follow-up care. Physical activity was objectively measured during 3 consecutive weekdays, using the ActiGraph accelerometer (model GT1M, Fort Walton Beach, Florida), in 3 different moments (1st, 6th, and 12th weeks). RESULTS The intervention group significantly increased daily PA index (from 278.2 ± 128.0 to 525.5 ± 153.4 counts per minute per day, P < .05) and time spent in moderate-intensity PA (from 16.8 ±12.6 to 63.7 ± 23.3 minutes per day, P < .05) during the intervention period. No changes were observed in the control group. CONCLUSIONS Patients participating in the home-based intervention increased PA throughout the day; moreover, they performed enough moderate-intensity PA to meet heath-related recommendations.

Impact of low cost strength training of dorsi- and plantar flexors on balance and functional mobility in institutionalized elderly people

Aim:  To evaluate the effects of a low cost strength training program of the dorsi‐ and ankle plantar flexors on muscle strength, balance and functional mobility, in elderly institutionalized subjects; and to determine the association between strength gain and balance and/or functional mobility gain.

Active travel to school, BMI and participation in organised and non-organised physical activity among Portuguese adolescents.

OBJECTIVES To assess the relationship between participation in organised (OPA) and non-organised physical activity (NOPA), commuting to school and BMI. METHODS Questionnaire assessing participation in OPA, NOPA, and travel behavior submitted in spring 2006 to 721 Portuguese secondary school students. Active travellers walked or biked (AT). Passive travellers drove or took the bus (PT). Height and weight were measured. RESULTS AT was related to NOPA among boys (odds ratio (OR)=1.8, p < or = 0.05) but not among girls. AT was unrelated to OPA. BMI was weakly associated with OPA (boys: OR=0.56, p < or = 0.05; girls: OR=0.54, p < or = 0.05) and not with NOPA. CONCLUSION After-school organised and non-organised physical activities do not predict active travelling to school among Portuguese adolescents.