Purpose Cystic Fibrosis(CF)is a multisystem disease associated with symptoms such as dyspnoea,tachycardia and tachyp-nea that may be related to changes in autonomic function and sensitive to improvement following insp...Purpose Cystic Fibrosis(CF)is a multisystem disease associated with symptoms such as dyspnoea,tachycardia and tachyp-nea that may be related to changes in autonomic function and sensitive to improvement following inspiratory muscle training(IMT).The aim of the present study was to investigate the effect of IMT on heart rate variability(HRV)and respiratory function in children.Methods Five CF and five matched controls(40%boys)performed a 4-weeks IMT programme,involving 30 breaths,twice a day.Weeks 1-2 of training were set at 40%of a participant's maximal strength index(S.Index),with week's 3-4 set at 50%.Participants wore an ActiHeart for three consecutive days at baseline and post-intervention and indices of HRV were derived.Standard measures of lung function were obtained along with health-related quality of life(HRQoL)using the CF-specific questionnaire(CFQ-R).Results IMT elicited clinically meaningful increases in respiratory muscle strength and respiratory symptom domain scores,but no improvements in respiratory volume,irrespective of group.Similarly,no significant improvements were found in HRQoL despite 62.5%of the population increased their HRQoL score.Post-intervention,CF participants showed a clinically meaningful decrease in the very low frequency(VLF)domain.Conclusion These results may indicate clinically meaningful changes in HRV and inspiratory muscle strength following a 4-week IMT intervention,although a more powerful study is required to draw further conclusions.Indeed,the trends for improved HRQoL support the need for such studies to ascertain the potential therapeutic role of IMT in those with CF.展开更多
Purpose The aim of this study was to determine the modulatory roles of biological maturity and age on the predictors of performance in youth swimmers and their stability over a six-month training cycle.Methods In tota...Purpose The aim of this study was to determine the modulatory roles of biological maturity and age on the predictors of performance in youth swimmers and their stability over a six-month training cycle.Methods In total,28 swimmers(10 pre-pubertal[6 boys],11.1±1.8 years;18 pubertal[8 boys],15.2±2.0 years old)and 26 untrained controls(15 pre-pubertal[10 boys],9.7±1.5 years;11 pubertal[6 boys],14.4±0.5 years old)were recruited.At baseline,3-and 6-months,participants completed an incremental ramp cycle test,isometric handgrip strength test and countermovement jumps,with speed assessed as a measure of performance in swimmers.Principle component analysis(PCA)identified factors that described youth swimmers’physical profile,with linear mixed models subsequently used to determine their interaction with age and maturity on performance.Results Aerobic fitness and upper body strength were significantly higher in the trained participants,irrespective of maturity status or time-point.Four key factors were identified through PCA(anthropometrics;strength;aerobic capacity;aerobic rate),accounting for 90%of the between parameter variance.Age exerted a widespread influence on swimming performance predic-tors,influencing all four factors,whilst maturity only influenced the aerobic factors.The key age of divergence was 13 years.Conclusion Overall,the present study found no evidence of a maturational threshold in the aerobic or strength-related response to training in youth.The influence of age on performance predictors suggests that utilising a single or select group of parameters to inform selection and/or talent identification throughout the dynamic processes of growth and maturation should be avoided.展开更多
文摘Purpose Cystic Fibrosis(CF)is a multisystem disease associated with symptoms such as dyspnoea,tachycardia and tachyp-nea that may be related to changes in autonomic function and sensitive to improvement following inspiratory muscle training(IMT).The aim of the present study was to investigate the effect of IMT on heart rate variability(HRV)and respiratory function in children.Methods Five CF and five matched controls(40%boys)performed a 4-weeks IMT programme,involving 30 breaths,twice a day.Weeks 1-2 of training were set at 40%of a participant's maximal strength index(S.Index),with week's 3-4 set at 50%.Participants wore an ActiHeart for three consecutive days at baseline and post-intervention and indices of HRV were derived.Standard measures of lung function were obtained along with health-related quality of life(HRQoL)using the CF-specific questionnaire(CFQ-R).Results IMT elicited clinically meaningful increases in respiratory muscle strength and respiratory symptom domain scores,but no improvements in respiratory volume,irrespective of group.Similarly,no significant improvements were found in HRQoL despite 62.5%of the population increased their HRQoL score.Post-intervention,CF participants showed a clinically meaningful decrease in the very low frequency(VLF)domain.Conclusion These results may indicate clinically meaningful changes in HRV and inspiratory muscle strength following a 4-week IMT intervention,although a more powerful study is required to draw further conclusions.Indeed,the trends for improved HRQoL support the need for such studies to ascertain the potential therapeutic role of IMT in those with CF.
文摘Purpose The aim of this study was to determine the modulatory roles of biological maturity and age on the predictors of performance in youth swimmers and their stability over a six-month training cycle.Methods In total,28 swimmers(10 pre-pubertal[6 boys],11.1±1.8 years;18 pubertal[8 boys],15.2±2.0 years old)and 26 untrained controls(15 pre-pubertal[10 boys],9.7±1.5 years;11 pubertal[6 boys],14.4±0.5 years old)were recruited.At baseline,3-and 6-months,participants completed an incremental ramp cycle test,isometric handgrip strength test and countermovement jumps,with speed assessed as a measure of performance in swimmers.Principle component analysis(PCA)identified factors that described youth swimmers’physical profile,with linear mixed models subsequently used to determine their interaction with age and maturity on performance.Results Aerobic fitness and upper body strength were significantly higher in the trained participants,irrespective of maturity status or time-point.Four key factors were identified through PCA(anthropometrics;strength;aerobic capacity;aerobic rate),accounting for 90%of the between parameter variance.Age exerted a widespread influence on swimming performance predic-tors,influencing all four factors,whilst maturity only influenced the aerobic factors.The key age of divergence was 13 years.Conclusion Overall,the present study found no evidence of a maturational threshold in the aerobic or strength-related response to training in youth.The influence of age on performance predictors suggests that utilising a single or select group of parameters to inform selection and/or talent identification throughout the dynamic processes of growth and maturation should be avoided.
