Your Canada Aerobic Community Heart Failure Companion Bridging Suggestions in your Training

This study aimed to compare physiological factors and cycle characteristics during cross-country (XC) roller-skiing at matched inclines and speeds using the double-poling (DP) and diagonal-stride (DS) sub-techniques in junior female and male XC skiers.
Twenty-three well-trained junior XC skiers (11 women, 12 men; age 18.2 ± 1.2yr.) completed two treadmill roller-skiing tests in a randomized order using either DP or DS. The exercise protocols were identical and included a 5min warm-up, 4 × 5min submaximal stages, and an incremental test to exhaustion, all performed at a 5° incline.
No significant three-way interactions were observed between sex, submaximal exercise intensity, and sub-technique. For the pooled sample, higher values were observed for DP versus DS during submaximal exercise for the mean oxygen uptake kinetics response time (33%), energy cost (18%), heart rate (HR) (9%), blood lactate concentration (5.1 versus 2.1mmol·L
), rating of perceived exertion (12%), and cycle rate (25%), while cycle length was lower (19%) (all P < 0.001). During the time-to-exhaustion (TTE) test, peak oxygen uptake ([Formula see text]O
peak), peak HR, and peak oxygen pulse were 8%, 2%, and 6% lower, respectively, for DP than DS, with a 29% shorter TTE during DP (pooled data, all P < 0.001).
In well-trained junior XC skiers, DP was found to exert a greater physiological load than DS during uphill XC roller-skiing at submaximal intensities. During the TTE test, both female and male athletes were able to ski for longer and reached markedly higher [Formula see text]O
peak values when using DS compared to DP.
In well-trained junior XC skiers, DP was found to exert a greater physiological load than DS during uphill XC roller-skiing at submaximal intensities. During the TTE test, both female and male athletes were able to ski for longer and reached markedly higher [Formula see text]O2peak values when using DS compared to DP.
The purpose of this study was to examine the composite, intra-individual, and inter-individual patterns of responses for deoxygenated hemoglobin and myoglobin (deoxy[heme]), oxygenated hemoglobin and myoglobin (oxy[heme]), total hemoglobin and myoglobin (total[heme]), and tissue saturation index (StO
%) during fatiguing, maximal, isokinetic, unilateral, and bilateral leg extensions.
Nine men (Mean ± SD; age = 21.9 ± 2.4 years; height = 181.8 ± 11.9cm; body mass = 85.8 ± 6.2kg) performed 50 unilateral and bilateral maximal, concentric, isokinetic leg extensions at 180°s
on two separate visits. The muscle oxygenation parameters assessed with near-infrared spectroscopy from the dominant leg and isokinetic torque were averaged for 2 consecutive repetitions at 5 repetition intervals. Separate 2 (Condition [Unilateral and Bilateral]) × 10 (Repetition [5-50]) repeated measures ANOVAs were performed to examine mean differences for normalized isokinetic torque and each muscle oxygenation parameter. Intra- and i.
The present findings indicated that the greater performance fatigability for unilateral versus bilateral fatiguing, maximal, isokinetic leg extensions was not attributable to differences in muscle oxygenation. Future studies of muscle oxygenation should report individual and composite fatigue-induced patterns of responses due to the substantial intra- and inter-individual variabilities.This study investigates the overall volumetric oxygen transfer coefficient (KLa) in multiphase hydrocarbon-based bioprocess under a range of hydrocarbon concentrations (HC), solid loadings (deactivated yeast) (SL) and superficial gas velocities (UG) in a bubble column reactor (BCR). KLa increased with increasing UG in the air-water system; due to an increase in the number of small bubbles which enhanced gas holdup. In air-water-yeast systems, the initial addition of yeast increased KLa significantly. Further increases in SL reduced KLa, due to increases in the bubble size with increasing SL. KLa decreased when HC was added in air-water-hydrocarbon systems. However, UG, SL and HC affected KLa differently in air-water-yeast-hydrocarbon systems an indication of the complex interactions between the yeast and hydrocarbon phases which changed the system's hydrodynamics and therefore affected KL. This work illustrates the effect of the operating conditions (SL, HC and UG) on oxygen transfer behaviour in multiphase systems.Natural nanomaterials, which play a very important role in environmental processes, are so far poorly studied. Firstly, the separation of nanoparticles from the bulk sample is a challenge. Secondly, the absence of reference natural nanomaterials makes it impossible to compare the results obtained by different researchers and develop a unified methodology for the separation and characterization of natural nanomaterials. Therefore, the development of reference natural nanomaterials is an urgent need of the environmental analytical chemistry. In this work, mineral nanoparticles (kaolinite, montmorillonite, muscovite, and quartz) have been studied as potential reference natural nanomaterials. A set of analytical methods including coiled-tube field-flow fractionation, scanning electron microscopy, dynamic light scattering, laser diffraction, inductively coupled plasma atomic emission, and mass spectrometry are applied to the separation and characterization of nanoparticles. It has been shown by laser diffraction that 93-98% of separated mineral nanoparticles are in the size range from about 40 to 300 nm, while 2-7% have size up to 830 nm. The size range of particles is confirmed by electron microscopy. Major (Al, Na, K, Ca, Fe), trace (Ti, Co, Cu, Zn, Tl, Pb, Bi, etc.), and rare earth elements have been determined in the suspensions of kaolinite, montmorillonite, and muscovite nanoparticles. Based on Al content, the concentration of mineral nanoparticles in suspensions is estimated. Agglomeration stability (consistency of size distribution) of nanoparticles at pH 6-8 is assessed. It has been shown that muscovite nanoparticles are stable at pH 7-8, whereas montmorillonite nanoparticles are stable only at pH 8 for at least 4 weeks. A noticeable agglomeration of kaolinite nanoparticles is observed at pH 6-8. Adenine sulfate Due to the low concentration of quartz nanoparticles, their characterization and stability assessment are hindered. The challenges of the development of reference natural nanomaterials are discussed.