Effect of High-Intensity Training and Asthma on the VO2 Kinetics of Adolescents

Purpose High-intensity interval training (HIIT) represents a potent stimulus to the dynamic oxygen uptake (V[Combining Dot Above]O2) response in adults but whether the same is evident in youth is unknown. HIIT has also been suggested to place a lower demand on the respiratory system, decreasing the likelihood of exacerbation in those with respiratory conditions, such as asthma.Methods Sixty-nine adolescents (13.6±0.9 years; 36 asthma) took part, 35 of which (17 asthma) participated in a 30-minute HIIT intervention three-times/week for six months. Each participant completed an incremental ramp test to volitional exhaustion and three heavy-intensity constant work-rate tests to determine the dynamic oxygen uptake (V[Combining Dot Above]O2), heart rate (HR) and deoxyhaemoglobin ([HHb]) response at baseline, mid-intervention, post-intervention and at a three-month follow-up.Results There was no influence of asthma at baseline or in response to the intervention. Participants in the intervention group demonstrated a faster V[Combining Dot Above]O2 time constant (τp) post-intervention (intervention: 29.2±5.7 vs. control: 34.2±6.5 s; P=0.003), with these differences maintained at follow-up (intervention: 32.5±5.5 vs. control: 37.3±8.7 s; P=0.008). The intervention was associated with a speeding of the [HHb] τ (Pre: 20.1±4.7 vs. Post: 18.2±4.1 s; P=0.05), compared to a slowing over the same time period in the control participants (Pre: 17.9±4.9 vs. Post: 20.1±4.6 s; P=0.012). HR kinetics were not altered (Pre: 46.5±12.2 vs. Post: 47.7±11.1 s; P=0.98).Conclusion These findings highlight the potential utility of school-based HIIT as a strategy to enhance the V[Combining Dot Above]O2 kinetics of youth, regardless of the presence of asthma

Identifying facilitators and barriers for adolescents participating in a school-based HIIT intervention: the eXercise for asthma with commando Joe’s® (X4ACJ) programme

BackgroundHigh-intensity interval training (HIIT) elicits numerous health benefits, but little evidence is available regarding the feasibility of delivering school-based HIIT interventions. The aim of this study was to explore adolescents’ perceptions of a 6-month, 3 × 30-min sessions per week, HIIT intervention delivered either before or after school.MethodEighty adolescents allocated to the intervention group (13.3 ± 1.0 years; 45 boys) were invited to take part in semi-structured focus groups post-intervention. Participants were categorised as attendees (≥40% attendance) or non-attendees (< 5% attendance). Data were transcribed verbatim and thematically analysed deductively, with key emergent themes represented using pen profiles.ResultsResults showed that a school-based HIIT intervention can be an enjoyable form of exercise. Irrespective of attendance, similar facilitators and barriers to participating were highlighted, including benefits of participation, content of the exercise session and the intervention instructor.ConclusionThis study provides support for the delivery of a HIIT intervention in a school setting but highlights the importance of a flexible design and delivery to accommodate competing interests. There is a need to educate adolescents on the possible benefits of participation and to make the sessions enjoyable in order to increase their extrinsic and intrinsic motivation to sustain participation

Asthma, body mass and aerobic fitness, the relationship in adolescents: The exercise for asthma with commando Joe’s® (X4ACJ) trial

Although an association has been suggested between asthma, obesity, fitness and physical activity, the relationship between these parameters remains to be elucidated in adolescents. Six-hundred and sixteen adolescents were recruited (334 boys; 13.0 ± 1.1years; 1.57 ± 0.10m; 52.6 ± 12.9kg), of which 155 suffered from mild-to-moderate asthma (78 boys). Participants completed a 20-metre shuttle run test, lung function and 7-day objective physical activity measurements and completed asthma control and quality of life questionnaires. Furthermore, 69 adolescents (36 asthma; 21 boys) completed an incremental ramp cycle ergometer test. Although participants with asthma completed significantly fewer shuttle runs than their peers, peak V̇O2 did not differ between the groups. However, adolescents with asthma engaged in less physical activity (53.9 ± 23.5 vs 60.5 ± 23.6minutes) and had higher BMI (22.2 ± 4.8 vs 20.4 ± 3.7kg·m-2), than their peers. Whilst a significant relationship was found between quality of life and cardiorespiratory fitness according to peak V̇O2, only BMI was revealed as a significant predictor of asthma status. The current findings highlight the need to use accurate measures of cardiorespiratory fitness rather than indirect estimates to assess the influence of asthma during adolescence. Furthermore, the present study suggests that BMI and fitness may be key targets for future interventions seeking to improve asthma quality of life

A Cryogenic Silicon Interferometer for Gravitational-wave Detection

The detection of gravitational waves from compact binary mergers by LIGO has opened the era of gravitational wave astronomy, revealing a previously hidden side of the cosmos. To maximize the reach of the existing LIGO observatory facilities, we have designed a new instrument that will have 5 times the range of Advanced LIGO, or greater than 100 times the event rate. Observations with this new instrument will make possible dramatic steps toward understanding the physics of the nearby universe, as well as observing the universe out to cosmological distances by the detection of binary black hole coalescences. This article presents the instrument design and a quantitative analysis of the anticipated noise floor

A cryogenic silicon interferometer for gravitational-wave detection

The detection of gravitational waves from compact binary mergers by LIGO has opened the era of gravitational wave astronomy, revealing a previously hidden side of the cosmos. To maximize the reach of the existing LIGO observatory facilities, we have designed a new instrument able to detect gravitational waves at distances 5 times further away than possible with Advanced LIGO, or at greater than 100 times the event rate. Observations with this new instrument will make possible dramatic steps toward understanding the physics of the nearby Universe, as well as observing the Universe out to cosmological distances by the detection of binary black hole coalescences. This article presents the instrument design and a quantitative analysis of the anticipated noise floor

Perceptions of asthma and exercise in adolescents with and without asthma

Objective: To elicit the views of adolescents, with and without asthma, about exercise and asthma, and the perceived benefits of and barriers to participation. The adolescent views elicited would subsequently inform the design of a high-intensity exercise intervention to improve asthma control. Methods: Fifty-four adolescents (age 13.1±0.9years; 26 with asthma) participated in twelve semi-structured group interviews. Questions were structured around knowledge, attitudes and beliefs towards asthma and its impact on exercise participation and lifestyle. The interviews were transcribed verbatim, thematically analysed and presented via diagrams of emergent themes. Ethical approval was granted by the institutional research ethics committee. Results: Fear of an asthma attack emerged as the main barrier to exercise, with many adolescents with asthma withdrawing from exercise as a coping strategy; many healthy adolescents perceived this withdrawal as laziness or an excuse. Despite this, the majority (81%) of adolescents with asthma reported exercise to be their most enjoyable activity. Adolescents suggested incorporating mixed activities, such as team games (e.g., rounders, football, netball), for future interventions to ensure adherence. Conclusions: Whilst exercise is important in the management of asthma, the tendency of those with asthma to withdraw from exercise to avoid adverse events could be addressed through a games-based high-intensity exercise intervention. Furthermore, educating all adolescents on asthma could simultaneously reduce stigmatisation and enhance exercise engagement

High-Intensity Interval Training Interventions in Children and Adolescents: A Systematic Review

BackgroundWhilst there is increasing interest in the efficacy of high-intensity interval training in children and adolescents as a time-effective method of eliciting health benefits, there remains little consensus within the literature regarding the most effective means for delivering a high-intensity interval training intervention. Given the global health issues surrounding childhood obesity and associated health implications, the identification of effective intervention strategies is imperative.ObjectivesThe aim of this review was to examine high-intensity interval training as a means of influencing key health parameters and to elucidate the most effective high-intensity interval training protocol.MethodsStudies were included if they: (1) studied healthy children and/or adolescents (aged 5–18 years); (2) prescribed an intervention that was deemed high intensity; and (3) reported health-related outcome measures.ResultsA total of 2092 studies were initially retrieved from four databases. Studies that were deemed to meet the criteria were downloaded in their entirety and independently assessed for relevance by two authors using the pre-determined criteria. From this, 13 studies were deemed suitable. This review found that high-intensity interval training in children and adolescents is a time-effective method of improving cardiovascular disease biomarkers, but evidence regarding other health-related measures is more equivocal. Running-based sessions, at an intensity of >90% heart rate maximum/100–130% maximal aerobic velocity, two to three times a week and with a minimum intervention duration of 7 weeks, elicit the greatest improvements in participant health.ConclusionWhile high-intensity interval training improves cardiovascular disease biomarkers, and the evidence supports the effectiveness of running-based sessions, as outlined above, further recommendations as to optimal exercise duration and rest intervals remain ambiguous owing to the paucity of literature and the methodological limitations of studies presently available

A Cryogenic Silicon Interferometer for Gravitational-wave Detection

The detection of gravitational waves from compact binary mergers by LIGO has opened the era of gravitational wave astronomy, revealing a previously hidden side of the cosmos. To maximize the reach of the existing LIGO observatory facilities, we have designed a new instrument that will have 5 times the range of Advanced LIGO, or greater than 100 times the event rate. Observations with this new instrument will make possible dramatic steps toward understanding the physics of the nearby universe, as well as observing the universe out to cosmological distances by the detection of binary black hole coalescences. This article presents the instrument design and a quantitative analysis of the anticipated noise floor

A Cryogenic Silicon Interferometer for Gravitational-wave Detection

The detection of gravitational waves from compact binary mergers by LIGO has opened the era of gravitational wave astronomy, revealing a previously hidden side of the cosmos. To maximize the reach of the existing LIGO observatory facilities, we have designed a new instrument able to detect gravitational waves at distances 5 times further away than possible with Advanced LIGO, or at greater than 100 times the event rate. Observations with this new instrument will make possible dramatic steps toward understanding the physics of the nearby Universe, as well as observing the Universe out to cosmological distances by the detection of binary black hole coalescences. This article presents the instrument design and a quantitative analysis of the anticipated noise floor