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McNarry MA, Lester L, Ellins EA, Halcox JP, Davies G, Winn CON, Mackintosh KA. Asthma and high-intensity interval training have no effect on clustered cardiometabolic risk or arterial stiffness in adolescents. Eur J Appl Physiol 2021; 121:1967-1978. [PMID: 33778908 PMCID: PMC8192411 DOI: 10.1007/s00421-020-04590-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 12/17/2020] [Indexed: 12/18/2022]
Abstract
PURPOSE Cardiometabolic risk, including arterial stiffness, is increasing in youth. Those with asthma are suggested to be particularly at risk of cardiovascular disease. Efficient and effective strategies are required to prevent the atherosclerotic process in youth. The purpose of this study was to investigate the effect of 6 months high-intensity interval training (HIIT) on cardiometabolic risk in youth with and without asthma. METHODS 65 adolescents (31 mild asthma; 34 non-asthma) were recruited, 32 (16 asthma) of whom were randomly allocated to receive HIIT three times per week for 6 months. At baseline, mid-intervention, post-intervention and at a 3-month follow-up, anthropometric, metabolic and vascular determinants of cardiometabolic risk were assessed. Following principal component analysis (PCA), linear mixed models were used to assess the influence of asthma, HIIT and their interaction. RESULTS Seven factors were identified which explained 88% of the common variance shared among the parameters. Those with asthma demonstrated lower arterial stiffness factor scores mid-intervention (P = 0.047) and lower cholesterol factor scores post-intervention (P = 0.022) but there was no effect of the intervention, or interaction effects, on any PCA-identified factor, at any time-point. HIIT was associated with a lower low-density lipoprotein and diastolic blood pressure at mid-intervention. DISCUSSION Neither arterial stiffness nor clustered cardiometabolic risk are influenced by HIIT in adolescents with or without asthma, despite important changes in blood lipid and pressure profiles. Blood pressure, augmentation and pulse wave velocity should be considered physiologically distinct constructs and as potential markers of cardiovascular health.
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Affiliation(s)
- M A McNarry
- Applied Sports, Technology, Exercise and Medicine Research Centre, College of Engineering, Swansea University, Bay Campus, Swansea, SA1 8EN, UK.
| | - L Lester
- School of Human Sciences, University of Western Australia, Perth, 6009, Australia
| | - E A Ellins
- Swansea University Medical School, Swansea University, Swansea, SA2 8PP, UK
| | - J P Halcox
- Swansea University Medical School, Swansea University, Swansea, SA2 8PP, UK
| | - G Davies
- Swansea University Medical School, Swansea University, Swansea, SA2 8PP, UK
| | - C O N Winn
- Applied Sports, Technology, Exercise and Medicine Research Centre, College of Engineering, Swansea University, Bay Campus, Swansea, SA1 8EN, UK
| | - K A Mackintosh
- Applied Sports, Technology, Exercise and Medicine Research Centre, College of Engineering, Swansea University, Bay Campus, Swansea, SA1 8EN, UK
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Denford S, Hill DM, Mackintosh KA, McNarry MA, Barker AR, Williams CA. Using photo-elicitation to explore perceptions of physical activity among young people with cystic fibrosis. BMC Pulm Med 2019; 19:220. [PMID: 31771568 PMCID: PMC6878712 DOI: 10.1186/s12890-019-0985-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 11/06/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Physical activity is recommended in the management of cystic fibrosis (CF). The aim of this study was to explore motives, barriers and enablers to physical activity among this population. METHODS Twelve participants (12-18 years) were recruited via convenience sampling. Photo-elicitation alongside semi-structured interviews were used to explore participants' views and experiences of physical activity. RESULTS Our findings revealed motives for physical activity including health, enjoyment and autonomy. Those with families who valued physical activity tended to have positive attitudes towards physical activity, and valued and integrated it into their lives. Moreover, they were likely to be intrinsically motivated to be active. Several factors enable and act as barriers to physical activity. Whilst CF influenced physical activity, the majority of enablers and barriers raised where congruent with the general populations. CONCLUSION This study provides support that healthcare providers should encourage both young people with CF and their families to be active, and subsequently informs the development of clinical interventions to support physical activity among young people with CF and their families.
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Affiliation(s)
- S Denford
- Children's Health and Exercise Research Centre, Sport and Health Sciences, University of Exeter, St. Luke's Campus, Heavitree Road, Exeter, EX1 2LU, UK.
| | - D M Hill
- Applied Sports Science, Technology, Exercise and Medicine Research Centre (A-STEM), Swansea University, Bay Campus, Swansea, UK
| | - K A Mackintosh
- Applied Sports Science, Technology, Exercise and Medicine Research Centre (A-STEM), Swansea University, Bay Campus, Swansea, UK
| | - M A McNarry
- Applied Sports Science, Technology, Exercise and Medicine Research Centre (A-STEM), Swansea University, Bay Campus, Swansea, UK
| | - A R Barker
- Children's Health and Exercise Research Centre, Sport and Health Sciences, University of Exeter, St. Luke's Campus, Heavitree Road, Exeter, EX1 2LU, UK
| | - C A Williams
- Children's Health and Exercise Research Centre, Sport and Health Sciences, University of Exeter, St. Luke's Campus, Heavitree Road, Exeter, EX1 2LU, UK
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Larribaut J, Gruet M, McNarry MA, Mackintosh KA, Verges S. Methodology and reliability of respiratory muscle assessment. Respir Physiol Neurobiol 2019; 273:103321. [PMID: 31629881 DOI: 10.1016/j.resp.2019.103321] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 10/11/2019] [Accepted: 10/14/2019] [Indexed: 11/26/2022]
Abstract
The optimal method for respiratory muscle endurance (RME) assessment remains unclear. This study assessed the test-retest reliability of two RME-test methodologies. Fifteen healthy adults attended the laboratory on four occasions, separated by 5 ± 2 days, and completed each test in a random, "one on two" order. They performed spirometry testing, maximal respiratory pressure assessment and two different RME tests: an inspiratory resistive breathing (IRB) and an isocapnic hyperpnea endurance (IHE) test. Typical error, expressed as coefficient of variation, for IRB maximal inspiratory pressure (MIP) and IHE maximal ventilation were 12.21 (8.85-19.67) % and 10.73 (7.78-17.29) %, respectively. Intraclass correlation coefficients for the same parameters were 0.83 (0.46-0.94) and 0.80 (0.41-0.93), respectively. No correlations were found between RME parameters derived from the IHE and IRB tests (all p > 0.05). Significant positive correlations were found between both IRB and IHE outcomes and spirometry parameters, MIP and maximal expiratory pressure (p < 0.05). Given these results, IRB and IHE appear to be suitable for RME testing in healthy people, although they may reflect different physiological mechanisms (respiratory mechanics and respiratory muscle capacity for IHE test vs. inspiratory muscle capacity for IRB test). Future studies are therefore warranted that compare IRB and IHE tests in clinical settings.
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Affiliation(s)
- J Larribaut
- HP2 Laboratory, INSERM, Grenoble Alpes University, Grenoble, France
| | - M Gruet
- LAMHESS, Université de Toulon, France; Unité de Recherche Impact de l'Activité Physique sur la Santé, UR IAPS n°201723207F, France.
| | - M A McNarry
- A-STEM, Swansea University, Swansea, Wales, UK
| | | | - S Verges
- HP2 Laboratory, INSERM, Grenoble Alpes University, Grenoble, France
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Runacres A, Bezodis NE, Mackintosh KA, McNarry MA. The reliability of force-velocity-power profiling during over-ground sprinting in children and adolescents. J Sports Sci 2019; 37:2131-2137. [PMID: 31130073 DOI: 10.1080/02640414.2019.1622316] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Anaerobic performance in youth has received little attention partly due to the lack of a "gold-standard" measurement. However, force-velocity-power (F-v-P) profiling recently showed high reliability and validity in trained adults. Therefore, the aim was to determine the reliability of F-v-P profiling in children and adolescents. Seventy-five children (60 boys, 15 girls; age: 14.1 ± 2.6 years) completed three 30 m sprints. Velocity was measured at 46.875 Hz using a radar device. The F-v-P profile was fitted to a velocity-time curve allowing instantaneous power variables to be calculated. Reliability was assessed using the intra-class correlation coefficient (ICC), coefficient of variation (CV), standard error of measurement (SEM) and smallest worthwhile change (SWC). High reliability was evident for absolute peak (Ppeak) and mean power (Pmean), Ppeak and Pmean expressed relative to body mass, peak and mean velocity, 30 m sprint time, peak horizontal force (F0), relative F0, mechanical efficiency index and fatigue rate (ICC: 0.75-0.88; CV: 1.9-9.4%) with time to peak power demonstrating moderate reliability (ICC: 0.50; CV: 9.5%). The F-v-P model demonstrated at least moderate reliability for all variables. This therefore provides a potential alternative for paediatric researchers assessing sprint performance and the underlying kinetics.
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Affiliation(s)
- A Runacres
- a A-STEM , Swansea University , Swansea , UK
| | - N E Bezodis
- a A-STEM , Swansea University , Swansea , UK
| | | | - M A McNarry
- a A-STEM , Swansea University , Swansea , UK
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Runacres A, Mackintosh KA, McNarry MA. The effect of constant-intensity endurance training and high-intensity interval training on aerobic and anaerobic parameters in youth. J Sports Sci 2019; 37:2492-2498. [PMID: 31319760 DOI: 10.1080/02640414.2019.1644890] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
INTRODUCTION High-Intensity Interval Training (HIIT) and Constant-Intensity Endurance Training (CIET) improves peak oxygen uptake (V̇O2) similarly in adults; but in children this remains unclear, as does the influence of maturity. METHODS Thirty-seven boys formed three groups: HIIT (football; n = 14; 14.3 ± 3.1 years), CIET (distance runners; n = 12; 13.1 ± 2.5 years) and a control (CON) group (n = 11; 13.7 ± 3.2 years). Peak V̇O2 and gas exchange threshold (GET) were determined from a ramp test and anaerobic performance using a 30 m sprint pre-and-post a three-month training cycle. RESULTS The HIIT groups peak V̇O2 was significantly higher than the CON group pre (peak V̇O2: 2.54 ± 0.63 l·min-1 vs 2.03 ± 0.53 l·min-1, d = 0.88; GET: 1.41 ± 0.26 l·min-1 vs 1.13 ± 0.29 l·min-1, d = 1.02) and post-training (peak V̇O2: 2.63 ± 0.73 l·min-1 vs 2.08 ± 0.64 l·min-1, d = 0.80; GET: 1.32 ± 0.33 l·min-1 vs 1.15 ± 0.38 l·min-1, d = 0.48). All groups showed a similar magnitude of change during the training (p > 0.05). CONCLUSION HIIT was not superior to CIET for improving aerobic or anaerobic parameters in adolescents. Secondly, pre- and post-pubertal participants demonstrated similar trainability.
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Affiliation(s)
- A Runacres
- College of Engineering, Swansea University , Wales , UK
| | | | - M A McNarry
- College of Engineering, Swansea University , Wales , UK
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McNarry MA, Lewis MJ, Wade N, Davies GA, Winn C, Eddolls WTB, Stratton GS, Mackintosh KA. Effect of asthma and six-months high-intensity interval training on heart rate variability during exercise in adolescents. J Sports Sci 2019; 37:2228-2235. [PMID: 31164059 DOI: 10.1080/02640414.2019.1626115] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Little is known regarding the influence of asthma and exercise, and their interaction, on heart rate variability (HRV) in adolescents. Thirty-one adolescents with asthma (13.7±0.9 years; 21.9±3.9 kg·m-2; 19 boys, 12 girls) and thirty-three healthy adolescents (13.8±0.9 years; 20.3±3.2 kg·m-2; 16 boys, 17 girls) completed an incremental ramp test and three heavy-intensity constant-work-rate cycle tests. Thirteen adolescents (7 boys, 6 girls; 6 asthma, 7 control) completed six-months high-intensity interval training (HIIT) and were compared to age- and sex-matched controls. Standard time-domain, frequency-domain and non-linear indices of HRV were derived at baseline, three- and six-months. Asthma did not influence HRV at baseline or following HIIT. Total power, low frequency and normalised low frequency power, and sympathovagal balance increased at three-months in HIIT, subsequently declining towards baseline at six-months. Normalised high frequency power was reduced at three-months in both groups, which was sustained at six-months. No effects of HIIT were observed in the time-domain nor in the non-linear indices. HRV was not influenced by asthma, potentially because such derangements are a function of disease progression, severity or duration. HIIT may be associated with a short-term shift towards greater sympathetic predominance during exercise, perhaps caused by physiological overload and fatigue.
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Affiliation(s)
- M A McNarry
- a Applied Sports Technology Exercise and Medicine Research Centre, Swansea University , Swansea , UK
| | - M J Lewis
- a Applied Sports Technology Exercise and Medicine Research Centre, Swansea University , Swansea , UK
| | | | - G A Davies
- b Swansea University Medical School, Singleton Campus, Swansea University , Swansea , UK
| | - Con Winn
- a Applied Sports Technology Exercise and Medicine Research Centre, Swansea University , Swansea , UK.,b Swansea University Medical School, Singleton Campus, Swansea University , Swansea , UK
| | - W T B Eddolls
- a Applied Sports Technology Exercise and Medicine Research Centre, Swansea University , Swansea , UK
| | - G S Stratton
- a Applied Sports Technology Exercise and Medicine Research Centre, Swansea University , Swansea , UK
| | - K A Mackintosh
- a Applied Sports Technology Exercise and Medicine Research Centre, Swansea University , Swansea , UK
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Denford S, Mackintosh KA, McNarry MA, Barker AR, Williams CA. Promotion of physical activity for adolescents with cystic fibrosis: a qualitative study of UK multi disciplinary cystic fibrosis teams. Physiotherapy 2019; 106:111-118. [PMID: 30992157 DOI: 10.1016/j.physio.2019.01.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 01/08/2019] [Indexed: 11/24/2022]
Abstract
BACKGROUND The Cystic Fibrosis Trust recently published a standards of care document which stated that patients should be given a physical activity (PA) programme based on their motivations, fitness, and willingness to be active. However, there remains much debate regarding the roles and responsibilities for PA promotion, as well as "optimal" recommendations and advice. This study aimed to qualitatively explore cystic fibrosis (CF) multidisciplinary teams (MDTs) advice, recommendations and practices relating to PA promotion for adolescents with CF. METHOD Semi-structured interviews were conducted with fifteen members of CF MDTs (11 physiotherapists, two dieticians and two paediatricians). Thematic analysis was used to analyse the data. RESULTS Major themes identified were: (1) structure of MDTs, (2) recommendations relating to intensities, durations and types of PA, and (3) use of exercise testing. Participants reported variation between MDTs in terms of who is responsible for promoting and supporting PA, the nature of advice given to patients, and the use of exercise testing. Participants consistently lacked confidence in their own or others' knowledge to provide standardised recommendations to patients and highlighted that PA promotion and support was often overlooked during busy periods. CONCLUSIONS Despite its importance, PA support and promotion is not always prioritised. MDTs lack confidence in their ability to promote PA. Standardised advice and training relating to optimal intensities, durations and types of PA would provide a baseline from which to individualise advice to each patient and could increase confidence in PA promotion among MDTs.
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Affiliation(s)
- S Denford
- Children's Health and Exercise Research Centre, Sport and Health Sciences, University of Exeter, St Luke's Campus, Exeter, UK.
| | - K A Mackintosh
- Applied Sports Science, Technology, Exercise and Medicine Research Centre (A-STEM), Swansea University, Bay Campus, Swansea, UK
| | - M A McNarry
- Applied Sports Science, Technology, Exercise and Medicine Research Centre (A-STEM), Swansea University, Bay Campus, Swansea, UK
| | - A R Barker
- Children's Health and Exercise Research Centre, Sport and Health Sciences, University of Exeter, St Luke's Campus, Exeter, UK
| | - C A Williams
- Children's Health and Exercise Research Centre, Sport and Health Sciences, University of Exeter, St Luke's Campus, Exeter, UK
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Winn CON, Mackintosh KA, Eddolls WTB, Stratton G, Wilson AM, Rance JY, Doull IJM, McNarry MA, Davies GA. Perceptions of asthma and exercise in adolescents with and without asthma. J Asthma 2017; 55:868-876. [DOI: 10.1080/02770903.2017.1369992] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- C. O. N. Winn
- Swansea University Medical School, Swansea University, Swansea, Wales, UK
- Applied Sports Technology Exercise and Medicine Research Centre, College of Engineering, Swansea University, Swansea, Wales, UK
| | - K. A. Mackintosh
- Applied Sports Technology Exercise and Medicine Research Centre, College of Engineering, Swansea University, Swansea, Wales, UK
| | - W. T. B. Eddolls
- Applied Sports Technology Exercise and Medicine Research Centre, College of Engineering, Swansea University, Swansea, Wales, UK
| | - G. Stratton
- Applied Sports Technology Exercise and Medicine Research Centre, College of Engineering, Swansea University, Swansea, Wales, UK
| | - A. M. Wilson
- Norwich Medical School, University of East Anglia, Norwich, England, UK
| | - J. Y. Rance
- College of Human and Health Sciences, Swansea University, Swansea, Wales, UK
| | - I. J. M. Doull
- Department of Paediatric Respiratory Medicine and Paediatric Cystic Fibrosis Centre, Children's Hospital for Wales, Cardiff, Wales, UK
| | - M. A. McNarry
- Applied Sports Technology Exercise and Medicine Research Centre, College of Engineering, Swansea University, Swansea, Wales, UK
| | - G. A. Davies
- Swansea University Medical School, Swansea University, Swansea, Wales, UK
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McNarry MA, Wilson RP, Holton MD, Griffiths IW, Mackintosh KA. Investigating the relationship between energy expenditure, walking speed and angle of turning in humans. PLoS One 2017; 12:e0182333. [PMID: 28796796 PMCID: PMC5552125 DOI: 10.1371/journal.pone.0182333] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 07/17/2017] [Indexed: 12/05/2022] Open
Abstract
Recent studies have suggested that changing direction is associated with significant additional energy expenditure. A failure to account for this additional energy expenditure of turning has significant implications in the design and interpretation of health interventions. The purpose of this study was therefore to investigate the influence of walking speed and angle, and their interaction, on energy expenditure in 20 healthy adults (7 female; 28±7 yrs). On two separate days, participants completed a turning protocol at one of 16 speed- (2.5, 3.5, 4.5, 5.5 km∙h-1) and angle (0, 45, 90, 180°) combinations, involving three minute bouts of walking, interspersed by three minutes seated rest. Each condition involved 5 m of straight walking before turning through the pre-determined angle with the speed dictated by a digital, auditory metronome. Tri-axial accelerometry and magnetometry were measured at 60 Hz, in addition to gas exchange on a breath-by-breath basis. Mixed models revealed a significant main effect for speed (F = 121.609, P < 0.001) and angle (F = 19.186, P < 0.001) on oxygen uptake ( V˙O2) and a significant interaction between these parameters (F = 4.433, P < 0.001). Specifically, as speed increased, V˙O2 increased but significant increases in V˙O2 relative to straight line walking were only observed for 90° and 180° turns at the two highest speeds (4.5 and 5.5 km∙hr-1). These findings therefore highlight the importance of accounting for the quantity and magnitude of turns completed when estimating energy expenditure and have significant implications within both sport and health contexts.
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Affiliation(s)
- M. A. McNarry
- Applied Sports, Technology, Exercise and Medicine Research Centre, College of Engineering, Swansea University, Swansea, United Kingdom
- * E-mail:
| | - R. P. Wilson
- Swansea Lab for Animal Movement, Biosciences, College of Science, Swansea University, Swansea, United Kingdom
| | - M. D. Holton
- Visual Computing, Computer Science, College of Science, Swansea University, Swansea, United Kingdom
| | - I. W. Griffiths
- Applied Sports, Technology, Exercise and Medicine Research Centre, College of Engineering, Swansea University, Swansea, United Kingdom
| | - K. A. Mackintosh
- Applied Sports, Technology, Exercise and Medicine Research Centre, College of Engineering, Swansea University, Swansea, United Kingdom
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Mackintosh KA, Montoye AHK, Pfeiffer KA, McNarry MA. Investigating optimal accelerometer placement for energy expenditure prediction in children using a machine learning approach. Physiol Meas 2016; 37:1728-1740. [DOI: 10.1088/0967-3334/37/10/1728] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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McNarry MA, Mackintosh KA, Stoedefalke K. Longitudinal investigation of training status and cardiopulmonary responses in pre- and early-pubertal children. Eur J Appl Physiol 2014; 114:1573-80. [PMID: 24770727 DOI: 10.1007/s00421-014-2890-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 04/07/2014] [Indexed: 10/25/2022]
Abstract
PURPOSE The presence of a maturational threshold that modulates children's physiological responses to exercise training continues to be debated, not least due to a lack of longitudinal evidence to address this question. The purpose of this study was to investigate the interaction between swim-training status and maturity in nineteen trained (T, 10 ± 1 years, -2.4 ± 1.9 years pre-peak height velocity, 8 boys) and fifteen untrained (UT, 10 ± 1 years, -2.3 ± 0.9 years pre-peak height velocity, 5 boys) children, at three annual measurements. METHODS In addition to pulmonary gas exchange measurements, stroke volume (SV) and cardiac output ([Formula: see text]) were estimated by thoracic bioelectrical impedance during incremental ramp exercise. RESULTS At baseline and both subsequent measurement points, trained children had significantly (P < 0.05) higher peak oxygen uptake (year 1 T 1.75 ± 0.34 vs. UT 1.49 ± 0.22; year 2 T 2.01 ± 0.31 vs. UT 1.65 ± 0.08; year 3 T 2.07 ± 0.30 vs. UT 1.77 ± 0.16 l min(-1)) and [Formula: see text] (year 1 T 15.0 ± 2.9 vs. UT 13.2 ± 2.2; year 2 T 16.1 ± 2.8 vs. UT 13.8 ± 2.9; year 3 T 19.3 ± 4.4 vs. UT 16.0 ± 2.7 l min(-1)). Furthermore, the SV response pattern differed significantly with training status, demonstrating the conventional plateau in UT but a progressive increase in T. Multilevel modelling revealed that none of the measured pulmonary or cardiovascular parameters interacted with maturational status, and the magnitude of the difference between T and UT was similar, irrespective of maturational status. CONCLUSION The results of this novel longitudinal study challenge the notion that differences in training status in young people are only evident once a maturational threshold has been exceeded.
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Affiliation(s)
- M A McNarry
- College of Engineering, Swansea University, Singleton Park, Swansea, SA2 8PP, Wales, UK,
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