Changes in Sitting Time, Screen Exposure and Physical Activity during COVID-19 Lockdown in South American Adults: A Cross-Sectional Study.

The worldwide prevalence of insufficient physical activity (PA) and prolonged sedentary behavior (SB) were high before the coronavirus (COVID-19) pandemic. Measures that were taken by governments (such as home confinement) to control the spread of COVID-19 may have affected levels of PA and SB. This cross-sectional study among South American adults during the first months of COVID-19 aims to (i) compare sitting time (ST), screen exposure, moderate PA (MPA), vigorous PA (VPA), and moderate-to-vigorous PA (MVPA) before and during lockdown to sociodemographic correlates and (ii) to assess the impact of lockdown on combinations of groups reporting meeting/not-meeting PA recommendations and engaging/not-engaging excessive ST (≥7 h/day). Bivariate associations, effect sizes, and multivariable linear regressions were used. Adults from Argentina (n = 575) and Chile (n = 730) completed an online survey with questions regarding demographics, lifestyle factors, and chronic diseases. Mean reductions of 42.7 and 22.0 min./day were shown in MPA and VPA, respectively; while increases of 212.4 and 164.3 min./day were observed in screen and ST, respectively. Those who met PA recommendations and spent <7 h/day of ST experienced greatest changes, reporting greater than 3 h/day higher ST and more than 1.5 h/day lower MVPA. Findings from the present study suggest that efforts to promote PA to South American adults during and after COVID-19 restrictions are needed.

Effects of a rehabilitation program on microvascular function of CHD patients assessed by near-infrared spectroscopy.

This study aimed to evaluate whether near-infrared spectroscopy (NIRS)-derived reperfusion slope would detect the effects of a 12-week rehabilitation program on lower limb microvascular responsiveness in patients with coronary heart disease (CHD). Ten CHD patients (7 males and 3 females; 57.3 ± 7.6 years) underwent 12 weeks of drug treatment and high-intensity interval training (HIIT), 2 times per week (40 min/session). Microvascular responsiveness was assessed by using NIRS assessment of muscle oxygen saturation (StO2 ) combined with a vascular occlusion test (VOT) (NIRS-VOT). NIRS-VOT measures were taken at pre- and postintervention, and microvascular responsiveness was evaluated by examining the slope 2 of re-oxygenation rate (slope 2 StO2 ) and the area under the curve (StO2AUC ) of StO2 signal following cuff release subsequent to a 5-min occlusion period. The slope 2 StO2 was significantly steeper after 12 weeks of training (4.8 ± 1.6% sec-1 ) compared to the pretraining (3.1 ± 1.6% sec-1 ) (P < 0.05). The area under the curve for the change in the % StO2 signal during re-oxygenation increased significantly from 3494 ± 2372%∙sec at pretraining to 9006 ± 4311%∙sec at post-training (P < 0.05). NIRS-VOT technique detected the improvements of 12 weeks of rehabilitation program in the lower limb microvascular responsiveness of CHD patients.

Anthropometrics of Italian Senior Male Rugby Union Players: From Elite to Second Division.

UNLABELLED: Anthropometric evaluation of athletes is necessary to optimize talent identification and player development. OBJECTIVES: To provide a specific anthropometric reference database of senior male rugby players competing at different levels in the southern European region. DESIGN: Cross-sectional. METHODS: In 362 professional players (25 ± 4 y; 138 Italian national team, 97 first-division, and 127 second-division national championships) the authors measured mass, stature, and percentage body fat (plicometry). Mean, SD, and coefficient of variation were calculated for forwards and backs and for positional subgroups. Binomial logistic regression and receiver-operating-characteristic curve were performed to assess which variables best predicted level assignment (international vs national level). RESULTS: For all competitive levels forwards were significantly heavier and taller and had a larger percentage body fat and fat-free mass than backs. The lower the competitive level, the higher the within-role variability observed; furthermore, players in a specific positional subgroup were lighter, shorter, and fatter and had less fat-free mass. Fatfree mass is the variable that best predicts the likelihood of being classified as an international or national player (cutoff value 79.54 kg). CONCLUSIONS: The data confirm the specificity in the physical requirements of rugby in individual playing positions at all competitive levels and document significant differences among elite and 1st- and 2nd-division players in the same positional role. These differences may reflect the variable technical abilities, selection, training practices, and requirements of the game among these categories.

Determination of respiratory point compensation in healthy adults: Can non-invasive near-infrared spectroscopy help?

OBJECTIVES: We tested the hypothesis that the respiratory compensation point can be accurately determined in healthy participants during incremental cycling exercise using non-invasive near-infrared spectroscopy-derived measures of deoxygenated hemoglobin (deoxyHb). DESIGN: Validation study. METHODS: 118 healthy men (average age 47 ± 19 yrs, range 20-79 yrs) performed an incremental cycling test to exhaustion. Breath-by-breath pulmonary oxygen uptake (VO2) and other ventilatory and gas exchange variables were measured and used to determine respiratory compensation point. Vastus lateralis deoxyHb was monitored using a frequency domain multi-distance system near-infrared spectroscopy device and deoxyHb data were modeled with a piece-wise double-linear function from which the deoxyHb deflection point (deoxyHbDP) was determined. The absolute (L min(-1)) and relative (% maximal VO2 [VO 2max]) VO2 values associated with the respiratory compensation point and deoxyHbDP were determined for each individual. RESULTS: DeoxyHb increased as a function of exercise intensity up to a point (deoxyHbDP) after which the signal displayed a "near-plateau". The deoxyHbDP corresponded to a VO2 of 2.25 ± 0.69 L min(-1) (74 ± 12% VO 2max) which was not significantly different from the VO2 at respiratory compensation point (2.28 ± 0.70 L min(-1) and 74 ± 10% VO 2max, p < 0.05). Both indices were highly correlated (r(2) = 0.86) and Bland Altman analyses confirmed a non-significant bias for VO2 (-0.024 L min(-1)) concomitant with a small imprecision of 0.26 L min(-1). CONCLUSIONS: During incremental cycling exercise, the VO2 associated with the onset of a plateau in near-infrared spectroscopy-derived deoxyHb occurs in coincidence with the VO2 at respiratory compensation point suggesting that respiratory compensation point can be accurately estimated, non-invasively, using near-infrared spectroscopy-derived deoxyHb in alternative to the use of ventilatory-based techniques.