The study aimed to evaluate the association between the changes in ventilatory variables (tidal volume (Vt), respiratory rate (RR) and lung ventilation ($\stackrel{.}{\mathrm{V}}$E)) and deoxygenation of m.intescostales (∆SmO₂-m.intercostales) during a maximal incremental exercise in 19 male high-level competitive marathon runners. The ventilatory variables and oxygen consumption ($\stackrel{.}{\mathrm{V}}$O₂) were recorded breath-by-breath by exhaled gas analysis. A near-infrared spectroscopy device (MOXY^®) located in the right-hemithorax allowed the recording of SmO₂-m.intercostales. To explore changes in oxygen levels in muscles with high demand during exercise, a second MOXY^® records SmO₂-m.vastus laterallis. The triphasic model of exercise intensity was used for evaluating changes in SmO₂ in both muscle groups. We found that ∆SmO₂-m.intercostales correlated with $\stackrel{.}{\mathrm{V}}$O_2-peak (r = 0.65; p = 0.002) and the increase of $\stackrel{.}{\mathrm{V}}$E (r = 0.78; p = 0.001), RR (r = 0.54; p = 0.001), but not Vt (p = 0.210). The interaction of factors (muscles × exercise-phases) in SmO₂ expressed as an arbitrary unit (a.u) was significant (p = 0.005). At VT1 there was no difference (p = 0.177), but SmO₂-m.intercostales was higher at VT2 (p < 0.001) and $\stackrel{.}{\mathrm{V}}$O_2-peak (p < 0.001). In high-level competitive marathon runners, the m.intercostales deoxygenation during incremental exercise is directly associated with the aerobic capacity and increased lung ventilation and respiratory rate, but not tidal volume. Moreover, it shows less deoxygenation than m.vastus laterallis at intensities above the aerobic ventilatory threshold.

Purpose: The aim of this study was to identify socio-demographic correlates of total and domain-specific sedentary behavior (SB). Methods: Cross-sectional findings are based on 9218 participants (15–65 years) from the Latin American Study of Nutrition and Health. Data were collected between September 2014 and February 2015. Participants reported time spent in SB across specific domains. Sex, age, ethnicity, socioeconomic (SEL), and education level were used as sociodemographic indicators. Results: Participants spent a total of 373.3 min/day engaged in total SB. Men, younger adults, other ethnicities, higher SEL and educational level presented higher total SB when compared with women, older adults, white/Caucasian, and low SEL and educational level. Men spent more time on the playing videogames (b: 32.8: 95% CI: 14.6;51.1) and riding in an automobile (40.5: 31.3; 49.8). Computer time, reading, socializing or listening to music was higher in younger participants (<30 years) compared with those ≥50 years in the total sample. Compared to the low SEL and educational level groups, middle (11.7: 5.7; 17.6) and higher (15.1: 5.3; 24.9) SEL groups as well as middle (9.8: 3.6; 15.9) and higher (16.6: 6.5; 26.8) education level groups reported more time spent reading. Conclusion: Socio-demographic characteristics are associated with SB patterns (total and specific) across Latin American countries.

Maximal oxygen consumption (VO_2max) and maximal power output (P_max) play a preponderant role in the performance of rowers. This study aims to describe and analyse the kinetics of ventilatory and mechanical parameters in novice male rowers on the rowing ergometer. Twelve male novice rowers were part of the study – descriptive with a selective non-probabilistic cross-sectional design. The variables were VO_2max and P_max. The kinetics of the variables were observed in an Incremental Test (IT) and a 2,000 m time trial (2,000m_TT). The differences between the tests were established by Student’s t-test (p < 0.05). In both protocols, the VO_2max reached 330–345 s. Between IT and the 2,000m_TT there were significant differences in the VO_2max (52.7 ± 3.3 vs 55.9 ± 3.4 mLO₂·kg⁻¹·min⁻¹, p ˂ 0.01) and P_max (334.7 ± 20.2 vs 269.5 ± 31.3 W, p ˂ 0.001). The novice rowers’ low physiological capacity and efficiency generated instability in the power output kinetics. A very large delta was observed between the maximum and minimum power output. Exploring tests with a shorter duration for novice rowers (360 s) and improving power output control in the different tests are suggested.