scholarly journals Aerobic Fitness and Trainability in Healthy Youth: Gaps in Our Knowledge

2016 ◽  
Vol 28 (2) ◽  
pp. 171-177 ◽  
Author(s):  
Neil Armstrong ◽  
Melitta McNarry
Keyword(s):  
Young People ◽  
Aerobic Fitness ◽  
Exercise Intensity ◽  
Peak Oxygen Uptake ◽  
Chronological Age ◽  
Future Research ◽  
Criterion Measure ◽  
Transient Kinetics ◽  
Rapid Changes ◽  
Kinetics Of

Peak oxygen uptake (V̇O2) is widely recognized as the criterion measure of young people’s aerobic fitness. Peak V̇O2 in youth has been assessed and documented for over 75 years but the interpretation of peak V̇O2 and its trainability are still shrouded in controversy. Causal mechanisms and their modulation by chronological age, biological maturation and sex remain to be resolved. Furthermore, exercise of the intensity and duration required to determine peak V̇O2 is rarely experienced by most children and adolescents. In sport and in everyday life young people are characterized by intermittent bouts of exercise and rapid changes in exercise intensity. In this context it is the transient kinetics of pulmonary V̇O2 (pV̇O2), not peak V̇O2, which best describe aerobic fitness. There are few rigorously determined and appropriately analyzed data from young people’s pV̇O2 kinetics responses to step changes in exercise intensity. Understanding of the trainability of pV̇O2 kinetics is principally founded on comparative studies of trained and untrained youth and much remains to be elucidated. This paper reviews peak V̇O2, pV̇O2 kinetics, and their trainability in youth. It summarizes “what we know,” identifies significant gaps in our knowledge, raises relevant questions, and indicates avenues for future research.

Aerobic fitness

2017 ◽  
Author(s):  
Neil Armstrong ◽  
Alison M McManus
Keyword(s):  
Aerobic Fitness ◽  
Peak Oxygen Uptake ◽  
Chronological Age ◽  
V̇o2 Kinetics ◽  
Modelling Techniques ◽  
Blood Lactate Accumulation ◽  
Independent Effects ◽  
Biological Maturity ◽  
Kinetics Of ◽  
Integrated Responses

Peak oxygen uptake (V̇O2) is the criterion measure of young people's aerobic fitness, and blood lactate accumulation (BLA) is a useful indicator of aerobic fitness with reference to the ability to sustain submaximal exercise. In sport and in everyday life it is the pulmonary (p)V̇O2 kinetics of the non-steady state which best assess the integrated responses of the oxygen delivery system and the metabolic demands of the exercising muscle. Data analysis using sophisticated modelling techniques has enhanced understanding of sexual dimorphism and the independent effects of chronological age, body size, and biological maturity on peak V̇O2 and BLA. The extant data on young people's pV̇O2 kinetic responses to step changes in exercise intensity are sparse, but describe intriguing chronological age and sex differences across exercise domains. However, independent effects of biological maturation are yet to be revealed.

scholarly journals Game on: a cycling exergame can elicit moderate-to-vigorous intensity. A pilot study

2020 ◽  
Vol 6 (1) ◽  
pp. e000744 ◽  
Author(s):  
Jonathan Berg ◽  
Trine Moholdt
Keyword(s):  
Heart Rate ◽  
Pilot Study ◽  
Oxygen Uptake ◽  
Aerobic Exercise ◽  
Aerobic Fitness ◽  
Exercise Intensity ◽  
Preliminary Data ◽  
Peak Oxygen Uptake ◽  
Strong Positive Correlation ◽  
Vigorous Intensity

ObjectivesThe aims of this pilot study were to investigate oxygen uptake (V̇O2) while playing a cycling exergame to assess exercise intensity to determine its potential as a feasible exercise alternative to improve aerobic fitness, and to assess the validity of using heart rate (HR) to estimate V̇O2 in exergaming.MethodsFive males (age: 32±8; peak oxygen uptake (V̇O2peak): 47.9±7.8 mL·kg−1·min−1) and five females (age: 27±3; V̇O2peak: 33.9±4.6 mL·kg−1·min−1) played the cycling exergame ‘Pedal Tanks’ for 45 min, with measurements of HR and V̇O2.ResultsAverage and peak V̇O2 during exergaming were 61.7±10.1% and 78.3±11.7% of V̇O2peak, respectively, whereas average and peak HR were 80.0±9.4% and 91.5%±6.7% of HRpeak. There was a strong positive correlation between V̇O2 and HR for all participants (p<0.05) although estimated V̇O2 from HR was 9% higher than that measured during exergaming.ConclusionOur preliminary data suggest that the cycling exergame we investigated can elicit moderate-to-vigorous intensities and may therefore be a viable alternative to conventional aerobic exercise. The exercise intensity during exergaming was overestimated when using HR alone.

scholarly journals Aerobic fitness profile of youth soccer players: effects of chronological age and playing position

2016 ◽  
Vol 18 (6) ◽  
pp. 700 ◽  
Author(s):  
Giovani Dos Santos Cunha ◽  
André Luís Lopes ◽  
Jeam Marcel Geremia ◽  
Gabriela Tomedi Leites ◽  
Bruno Manfredini Baroni ◽  
...  
Keyword(s):  
Aerobic Fitness ◽  
Peak Oxygen Uptake ◽  
Soccer Players ◽  
Chronological Age ◽  
Position Effects ◽  
Youth Soccer ◽  
Biological Maturation ◽  
Maximal Aerobic Speed ◽  
Fitness Parameters ◽  
Positive Effect

DOI: http://dx.doi.org/10.5007/1980-0037.2016v18n6p700 To establish a profile of the aerobic fitness in young soccer players, it is critical to consider different intervenient factors such as maturity status, chronological age and playing position. The aim of this study was to identify the biological maturation, chronological age, and playing position effects on physical and physiological characteristics of young soccer players. Two hundred and one soccer players of 11-19 years old were divided into groups relative to their maturity status, chronological age and playing position. A maximal exercise test was performed to determine peak oxygen uptake (VO2peak) and ventilatory thresholds (VT1 and VT2) parameters in a treadmill. Biological maturation showed no significant effect on relative values (mL.kg-1.min-1) of VO2peak, VT2 and VT1 (0.004 < h2 < 0.039), but showed large positive effect on maximal aerobic speed (MAS) and speed at VT2 (VT2speed). Chronological age showed a medium positive effect on relative values of VO2peak, VT2 and VT1 (0.095 < h2 < 0.137) and a large positive effect on MAS and VT2speed. Relative values of VO2peak and VT1 showed no significant differences among groups for playing position (P>0.05; 0.044 < h2 < 0.051). However, goalkeepers showed significant lower relative values for VT2 and VT2speed than other playing positions and a medium positive effect was observed (P<0.05; 0.077 < h2 < 0.119). Chronological age showed a medium to large positive effect on aerobic fitness parameters, while biological maturation showed a positive effect only on MAS and VT2speed. Playing position showed a medium positive effect on VT2 and VT2speed. 

Maturity Status Does Not Exert Effects on Aerobic Fitness in Soccer Players After Appropriate Normalization for Body Size

2016 ◽  
Vol 28 (3) ◽  
pp. 456-465 ◽  
Author(s):  
Giovani Dos Santos Cunha ◽  
Marco Aurélio Vaz ◽  
Jeam Marcel Geremia ◽  
Gabriela T. Leites ◽  
Rafael Reimann Baptista ◽  
...  
Keyword(s):  
Body Size ◽  
Aerobic Fitness ◽  
Ventilatory Threshold ◽  
Peak Oxygen Uptake ◽  
Muscle Volume ◽  
Soccer Players ◽  
Chronological Age ◽  
Maximal Exercise Test ◽  
Positive Effect ◽  
Size Descriptor

The present study investigated the effects of pubertal status on peak oxygen uptake (VO2peak), respiratory compensation point (RCP), and ventilatory threshold (VT) in young soccer players using different body size descriptors. Seventy-nine soccer players (14 prepubescent, 38 pubescent and 27 postpubescent) participated in this study. A maximal exercise test was performed to determine the VO2peak, RCP, and VT. Ultrasonography was used to measure lower limb muscle volume (LLMV). LLMV (mL-b) was rated as the most effective body size descriptor to normalize VO2peak (mLO2•mL-0.43•min-1), RCP (mLO2•mL-0.48•min-1), and VT (mLO2•mL-0.40•min-1). The values of VO2peak, RCP, and VT relative to allometric exponents derived by LLMV were similar among groups (p > .05; 0.025 < η2 < 0.059) when the effect of chronological age was controlled. Allometric VO2peak, RCP, and VT values were: 100.1 ± 7.9, 107.5 ± 9.6, and 108.0 ± 10.3 mLO2.mL-0.43•min-1; 51.8 ± 5.3, 54.8 ± 4.7, and 57.3 ± 5.8 mLO2•mL-0.48•min-1; and 75.7 ± 7.1, 79.4 ± 7.0, and 80.9 ± 8.3 mLO2•mL-0.40•min-1 for prepubertal, pubertal, and postpubertal groups, respectively. Maturity status showed no positive effect on VO2peak, RCP, and VT when the data were properly normalized by LLMV in young soccer players. Allometric normalization using muscle volume as a body size descriptor should be used to compare aerobic fitness between soccer players heterogeneous in chronological age, maturity status, and body size.

Extraction of Auditory Information by Modulation of Neuronal Ion Channels

2018 ◽  
pp. 272-300
Author(s):  
Leonard K. Kaczmarek
Keyword(s):  
Ion Channels ◽  
Neuronal Firing ◽  
Auditory Information ◽  
Auditory Neurons ◽  
Complex Sound ◽  
Medial Nucleus ◽  
Rapid Changes ◽  
Genes Encoding ◽  
Kinetics Of ◽  
Trapezoid Body

All neurons express a subset of over seventy genes encoding potassium channel subunits. These channels have been studied in auditory neurons, particularly in the medial nucleus of the trapezoid body. The amplitude and kinetics of various channels in these neurons can be modified by the auditory environment. It has been suggested that such modulation is an adaptation of neuronal firing patterns to specific patterns of auditory inputs. Alternatively, such modulation may allow a group of neurons, all expressing the same set of channels, to represent a variety of responses to the same pattern of incoming stimuli. Such diversity would ensure that a small number of genetically identical neurons could capture and encode many aspects of complex sound, including rapid changes in timing and amplitude. This review covers the modulation of ion channels in the medial nucleus of the trapezoid body and how it may maximize the extraction of auditory information.All neurons express a subset of over seventy genes encoding potassium channel subunits. These channels have been studied in auditory neurons, particularly in the medial nucleus of the trapezoid body. The amplitude and kinetics of various channels in these neurons can be modified by the auditory environment. It has been suggested that such modulation is an adaptation of neuronal firing patterns to specific patterns of auditory inputs. Alternatively, such modulation may allow a group of neurons, all expressing the same set of channels, to represent a variety of responses to the same pattern of incoming stimuli. Such diversity would ensure that a small number of genetically identical neurons could capture and encode many aspects of complex sound, including rapid changes in timing and amplitude. This review covers the modulation of ion channels in the medial nucleus of the trapezoid body and how it may maximize the extraction of auditory information.

Behavior change techniques in mobile apps targeting self-harm in young people: a systematic review

2021 ◽  
Author(s):  
Elena Panagiotopoulou ◽  
Celeste Peiris ◽  
Daniel Hayes
Keyword(s):  
Young People ◽  
Behavior Change ◽  
Dialectical Behavior Therapy ◽  
Mobile Apps ◽  
Mental Healthcare ◽  
Future Research ◽  
Active Components ◽  
Behavior Change Techniques ◽  
Other Information ◽  
Self Harm

Abstract Despite the high prevalence of self-harm among young people, as well as their extensive use of mobile apps for seeking support with their mental healthcare, it is unclear whether the design of mobile apps aimed at targeting self-harm is underpinned by behavior change techniques (BCTs). To systematically analyze and identify (a) what BCTs and (b) what theories are present in self-harm apps for young people in an attempt to understand their active components. Systematic searches in Apple store, followed by thorough screening, were conducted to identify free mobile apps targeting self-harm in young people. Five apps met the inclusion criteria and were used by trained researchers, who coded identified features against the BCT Taxonomy V1. Despite the majority of apps being underpinned by principles of Dialectical Behavior Therapy (DBT), no other information is available about specific theories underpinning these apps. Nineteen of the 93 BCTs were identified across the five apps. The most frequently used BCT was “Distraction” (54.2%), offering ideas for activities to distract users from self-harming. Other techniques that were used often were “Social Support (unspecified)” (27.0%) and “Behavior Substitution” (10.6%). This study provides the first analysis of BCTs present in mental health apps which are designed to target the reduction of self-harm in young people. Future research is needed to evaluate the effectiveness of the apps, as well as assess the effectiveness of the BCTs present.

scholarly journals Polyelectrolyte Gels: A Unique Class of Soft Materials

Gels ◽  
2021 ◽  
Vol 7 (3) ◽  
pp. 102
Author(s):  
Ferenc Horkay
Keyword(s):  
Exchange Process ◽  
Interaction Strength ◽  
Soft Materials ◽  
Industrial Applications ◽  
Future Research ◽  
Swelling Kinetics ◽  
Polyelectrolyte Gels ◽  
Ion Exchange Process ◽  
Counter Ions ◽  
Kinetics Of

The objective of this article is to introduce the readers to the field of polyelectrolyte gels. These materials are common in living systems and have great importance in many biomedical and industrial applications. In the first part of this paper, we briefly review some characteristic properties of polymer gels with an emphasis on the unique features of this type of soft material. Unsolved problems and possible future research directions are highlighted. In the second part, we focus on the typical behavior of polyelectrolyte gels. Many biological materials (e.g., tissues) are charged (mainly anionic) polyelectrolyte gels. Examples are shown to illustrate the effect of counter-ions on the osmotic swelling behavior and the kinetics of the swelling of model polyelectrolyte gels. These systems exhibit a volume transition as the concentration of higher valence counter-ions is gradually increased in the equilibrium bath. A hierarchy is established in the interaction strength between the cations and charged polymer molecules according to the chemical group to which the ions belong. The swelling kinetics of sodium polyacrylate hydrogels is investigated in NaCl solutions and in solutions containing both NaCl and CaCl2. In the presence of higher valence counter-ions, the swelling/shrinking behavior of these gels is governed by the diffusion of free ions in the swollen network, the ion exchange process and the coexistence of swollen and collapsed states.

scholarly journals Social Media Use Among Young People in China: A Systematic Literature Review

SAGE Open ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 215824402110164
Author(s):  
Lian Tang ◽  
Siti Zobidah Omar ◽  
Jusang Bolong ◽  
Julia Wirza Mohd Zawawi
Keyword(s):  
Social Media ◽  
Young People ◽  
Literature Review ◽  
Systematic Literature Review ◽  
Media Use ◽  
Academic Research ◽  
Future Research ◽  
Research Topics ◽  
Social Media Use ◽  
Systematic Analysis

The widespread use of social media has promoted extensive academic research on this channel. The present study conducts a systematic analysis of extant research on social media use among young people in China. This systematic literature review aims to identify and bridge gaps in topics, theories, variables, and conceptual frameworks in studies of social media usage among young people in China. The study aims to develop a cause–effect framework that shows the causal relationships among research structures. The PRISMA method is used to review 20 articles drawn from the Scopus and Google Scholar databases. From the analysis, 10 major research topics, eight theories or models, and a complete framework of causal relations emerge. It is recommended that future research on social media should include a greater diversity of types of social media, investigate a wider range of research topics, and adopt different theories or models. Researchers should also implement a more complete and detailed systematic method for reviewing literature on social media research in China.

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