共查询到20条相似文献，搜索用时 31 毫秒
1.
Johna K. Register-Mihalik Kenneth L. Cameron Melissa C. Kay Zachary Y. Kerr Karen Y. Peck Megan N. Houston Laura A. Linnan Heidi Hennink-Kaminski Paula Gildner Steven J. Svoboda Stephen W. Marshall 《Journal of Science and Medicine in Sport》2019,22(5):509-515
Objectives
Non-disclosure of concussion complicates concussion management, but almost nothing is known about non-disclosure in military settings. This study describes concussion disclosure-related knowledge, attitudes, perceived social norms, perceived control, and intention. Additionally, the study identifies determinants of high intention to disclose concussion symptoms.Design
Cross sectional survey.Methods
First-year service academy cadets completed a cross-sectional survey to assess perceptions of concussion disclosure. Independent variables included: gender, race, ethnicity, high school athlete status, NCAA athlete status, previous concussion history, previous concussion education, socioeconomic proxy, concussion-related knowledge, attitudes about concussion, perceived social norms (perceived peer/organizational support and actions), and perceived control over disclosure. Log-binomial regression was used to identify determinants of high intention to disclose concussion symptoms.Results
A total of 972 first-year military service academy cadets completed the survey [85% response; age = 18.4 ± 0.9 y]. In the simple models, previous concussion history was associated with lower intention to disclose concussion symptoms. High perceived control over disclosure, higher concussion knowledge, more favorable attitudes and social norms about concussion were associated with high intention to disclose. In the multivariable model, a 10% shift towards more favorable perceived social norms (PR = 1.28; p < 0.001) and attitudes (PR = 1.07; p = 0.05) about concussion were associated with high intention to disclose concussion symptoms. High perceived control over disclosure was associated with high intention to disclose concussion symptoms (PR = 1.39; p = 0.08).Conclusions
Concussion-related perceived social norms, attitudes, and perceived control are associated with intention to disclose. Organizationally appropriate intervention strategies can be developed from these data. 相似文献2.
David R. Howell Julie C. Wilson Anna N. Brilliant Andrew J. Gardner Grant L. Iverson William P. Meehan 《Journal of Science and Medicine in Sport》2019,22(5):521-525
Objectives
To prospectively evaluate single/dual-task timed-up-and-go (TUG) and tandem gait performance among children and adolescents with concussion and healthy controls.Design
Repeated measures.Methods
Participants with concussion (n = 23; age = 14.1 ± 2.5 years; 52% female) completed single/dual-task TUG, tandem gait, and symptom assessments 6.7 ± 2.6 and 23.3 ± 6.1 days post injury. The control group (n = 27; age = 14.1 ± 2.3 years; 48% female) completed the same protocol initially and 10.7 ± 16.1 days later. All participants completed single-task (undivided attention) and dual-task (divided attention) tests. The primary outcome variable was test completion time.Results
The concussion group completed single-task (concussion group mean = 11.1 ± 1.9 vs. control group mean 9.9 ± 1.4 s, p = 0.027) and dual-task (concussion group mean = 14.4 ± 3.3 vs. control group mean 12.7 ± 1.9 s, p = 0.047) TUG tests slower than the control group across both time points. The concussion group completed dual-task tandem gait tests slower than the control group at both time points (21.3 ± 6.3 vs. 16.8 ± 5.5 s, p = 0.006), and were slower in the single-task condition at the first test (19.8 ± 5.4 vs. 13.8 ± 4.4 s, p = 0.003). Symptoms were significantly worse for the concussion group compared to the control group at the first (34.1 ± 21.4 vs. 3.9 ± 9.1, p < 0.001), but not the second test (9.1 ± 12.0 vs. 2.2 ± 6.8; p = 0.08).Conclusions
Slower dual-task TUG and tandem gait times were detected across both time points for the concussion group relative to the control group. In contrast, single-task tandem gait deficits appeared to improve in a similar fashion as symptoms, suggesting increased complexity from the addition of a cognitive task allows for the detection of persistent post-concussion deficits that might take longer to resolve. 相似文献3.
Shaun Porter Noah D. Silverberg Naznin Virji-Babul 《Journal of Science and Medicine in Sport》2019,22(4):397-402
Objectives
To examine the neurophysiological correlates and brain network organization underlying physical and cognitive exertion in active young adults.Design
Repeated measures.Methods
Thirteen healthy adults completed three exertion tasks in a counterbalanced order: a graded working memory task (anti-saccade and serial addition task (ASAT)), a graded exercise task (cycling on a stationary bicycle) (EX) and a combined graded working memory and exercise task (ASAT + EX). All three tasks were performed under five levels of increasing difficulty. Continuous EEG was recorded in each session. Heart rate, perceived exertion and accuracy on the working memory task were recorded throughout. Power spectrum analysis and graph theoretical analysis was applied to the EEG data.Results
Heart rate and perceived exertion increased with exercise load and in both the EX only and ASAT + EX tasks. Overall accuracy was equally high for the ASAT and ASAT + EX tasks. Analysis of EEG data showed there was an increase in theta power associated with the ASAT + EX task and increase in functional connectivity in the frontal regions of the brain compared with ASAT only task. Accuracy decreased in the last two blocks when the task was most difficult. This decrease in accuracy was associated with a decrease in theta power and a decrease in functional connectivity.Conclusions
Combined physical and mental exertion results in significant changes in perceived exertion, EEG theta power and network organization in healthy adults and will be valuable in revealing residual neurocognitive deficits after sports related concussion. 相似文献4.
Objective
To examine the association between sedentary leisure-time and all-cause mortality and differences in survival time.Design
Prospective cohort study.Methods
Information on sedentary leisure-time, defined as TV viewing and/or sitting reading, was collected from 72 003 Swedish adults who were 45–83 (median 60) years of age and completed a self-administered questionnaire at baseline and were followed up for 17 years through linkage with the Swedish Death Register.Results
The association between sedentary leisure-time and all-cause mortality was modified by age with a more pronounced association in middle-aged (<60 years of age) than in older adults (≥60 years of age) (p-interaction < 0.001). During follow-up, 3358 and 15 217 deaths occurred in the middle-aged and older age group, respectively. The multivariable-adjusted hazard ratios for the highest (>6 h/day) versus lowest category (<1 h/day) of sedentary leisure-time were 1.72 (95% confidence interval [CI] 1.29–2.30) in middle-aged adults and 1.19 (95% CI 1.05–1.36) in older adults. This corresponded to a difference in survival time of respectively 2.4 (95% CI ?4.1 to ?0.8) years and 1.5 (95% CI ?2.2 to ?0.7) years.Conclusions
Prolonged sedentary leisure-time was associated with a significantly decreased survival time up to 2.4 years in middle-aged adults. 相似文献5.
Tara Reilly Evan Walsh Barry Stockbrugger 《Journal of Science and Medicine in Sport》2019,22(5):591-595
Objectives
The Canadian Army fitness objective is FORCE COMBAT?. This consists of a 5 km march (35 kg) between 50–60 min, and the annual FORCE physical employment standard as a circuit without the usual 5 min rest intervals (FORCE circuit) in full fighting order (25 kg). The objective of this research was to determine the number of practice attempts required to establish reliability of FORCE COMBAT?. Additionally, this study aims to identify the minimal detectable change once reliability is established.Design
The study used a within participant design.Methods
33 Canadian Army members were divided into two groups. Group 1 performed four maximum effort attempts of FORCE COMBAT? completely. Group 2 performed only the FORCE circuit component, not the loaded march. On the fifth trial, the tasks of the groups were switched. Variability within and between trials of the FORCE circuit of FORCE COMBAT? were analysed based on six statistical factors of reliability.Results
Four statistical factors indicated that one maximal effort practice attempt of FORCE COMBAT? is required, as reflected in the variability of performance between trials 1 and 2. The minimum detectable change, highlighting inherent measurement error of the test was 89.18 s with 95% confidence.Conclusions
Results suggest that Canadian Army members should complete one FORCE COMBAT? in completion at maximal effort, before formal assessment. Further, members performing within 89 s of the recommended completion time, on FORCE COMBAT? should be offered a re-attempt (in its entirety). 相似文献6.
S. Kierkegaard I. Mechlenburg B. Lund L. Rømer K. Søballe U. Dalgas 《Journal of Science and Medicine in Sport》2019,22(4):413-419
Objectives
Little is known about hip function after hip arthroscopic surgery in patients with femoroacetabular impingement syndrome. Hence, the aim of the study was (1) to investigate changes in hip muscle strength from before to one year after hip arthroscopic surgery, (2) to compare patients with a reference group.Design
Cohort study with a cross-sectional comparison.Methods
Before and after hip arthroscopic surgery, patients underwent hip muscle strength testing of their hip flexors and extensors during concentric, isometric and eccentric contraction in an isokinetic dynamometer. Reference persons with no hip problems underwent tests at a single time point. Participants completed completed the Copenhagen Hip and Groin Outcome Score (HAGOS) questionnaire and physical capacity (stair climbing loaded and unloaded, stepping loaded and unloaded and jumping) tests.Results
After surgery, hip flexion strength improved during all tests (6–13%, p < 0.01) and concentric hip extension strength improved (4%, p = 0.002). Hip flexion and extension strength was lower for patients than for reference persons (9–13%, p < 0.05) one year after surgery. Higher hip extension strength after surgery was associated with better patient reported outcomes. Patients, who were unable to complete at minimum one test of physical capacity, demonstrated significantly weaker hip muscle strength. Compared with their healthy counterparts, female patients were more impaired than male patients.Conclusions
One year after surgery, patients improved their maximal hip muscle strength. When compared to reference persons, maximal hip muscle strength was still impaired. 相似文献7.
Amanda J.L. Watson Anna Timperio Helen Brown Kylie D. Hesketh 《Journal of Science and Medicine in Sport》2019,22(4):438-443
Objectives
To assess the feasibility and efficacy of a 6-week pilot active break program (ACTI-BREAK) on academic achievement, classroom behaviour and physical activity.Design
Pilot cluster randomised controlled trial.Methods
374 children in Year 3 and 4 (74% response) were recruited from six schools across Melbourne, Australia. Schools were randomised to the ACTI-BREAK intervention or usual teaching practice. The intervention involved teachers incorporating 3 × 5 min active breaks into their classroom routine daily. Academic achievement was assessed using 1-min tests in reading and mathematics; classroom behaviour at the individual and whole class level was observed by teachers; and physical activity levels were assessed using accelerometers. Multilevel mixed effects linear regression models were conducted using intention to treat (ITT) and per protocol (PP) analyses.Results
Significant intervention effects were found for classroom behaviour at the individual level (ITT B = 16.17; 95% CI: 6.58, 25.76); effects were stronger for boys (B = 21.42; 95% CI: 10.34, 32.49) than girls (B = 12.23; 95% CI: 1.52, 22.92). No effect was found for classroom behaviour at the whole class level, reading, math or physical activity. PP findings were similar.Conclusions
Implementing active breaks during class time may improve classroom behaviour, particularly for boys. There was no evidence to suggest that implementing active breaks had any adverse effect on academic achievement or classroom behaviour, which may encourage classroom teachers to incorporate active breaks into their routine. 相似文献8.
Maria Reyes Beltran-Valls Xanne Janssen Abdulaziz Farooq Ashley J. Adamson Mark S. Pearce Jessica K. Reilly Laura Basterfield John J. Reilly 《Journal of Science and Medicine in Sport》2019,22(4):450-455
Objective
The aims of our study were to quantify levels and investigate sex-specific changes and trajectories in VPA longitudinally from age 7 to 15 years.Design
Longitudinal observational study.Methods
Participants were part of the Gateshead Millennium Study. Measures were taken at age 7 (n = 507), 9 (n = 510), 12 (n = 425) and 15 years (n = 310). Vigorous physical activity was quantified objectively using ActiGraph GT1 M accelerometers over 5–7 days at the four time-points. Multilevel linear spline random-effects model and trajectory analysis to identify sub-groups were performed.Results
In boys, average VPA declined across childhood followed by an increase at adolescence, while in girls, average VPA declined across the 8-year study period. In boys, daily VPA decreased from 9-12 years (1.70 minutes/year) and increased from 12-15 years (1.99 minutes/year) (all p < 0.05). In girls daily VPA decreased from 7-9 years (1.70 minutes/year) (p < 0.05). Three VPA trajectories were identified which differed between the sexes. In boys, one group decreased from an initial relatively high level, one group, initially relatively low, increased, whereas the third one was stable over the 8-year period. In girls, all three groups declined from baseline.Conclusions
Marked sex and age-specific trajectories in VPA change were observed. These novel findings should help sports and exercise medicine specialists, as well as policy makers, in their effort to maintain or increase VPA in childhood and adolescence. 相似文献9.
Baruch Vainshelboim Ricardo M. Lima Elisabeth Edvardsen Jonathan Myers 《Journal of Science and Medicine in Sport》2019,22(4):403-407
Objectives
To evaluate the association between cardiorespiratory fitness (CRF), lung cancer incidence and cancer mortality in men.Design
Prospective cohort study.Methods
Maximal exercise testing was performed in 4920 men (59.2 ± 11.4 years) free from malignancy at baseline. Multivariate Cox hazard models adjusted for established cancer risk factors including smoking were analyzed for lung cancer incidence and cancer mortality among those who were diagnosed with lung cancer. Population attributable risks (PAR) of low CRF (<5 METs) were determined.Results
During 12.7 ± 7.5 years follow-up, 105 (2.1%) participants were diagnosed with lung cancer and 83 (79%) of those died from cancer after 3.6 ± 4.6 years from diagnosis. CRF was inversely and independently associated with cancer outcomes. A 1-MET increase and categories of moderate and high CRF were associated with 10%, 47% and 65% reduction in lung cancer incidence (p = 0.002), and 13%, 58% and 76% reduction in cancer mortality (p = 0.002), respectively. Also, individuals who were diagnosed with lung cancer and were at moderate or high CRF categories at baseline exhibited longer survival time (p < 0.001). The PARs% for lung cancer incidence and cancer mortality were 8.7% and 18.5%, respectively.Conclusions
Higher CRF is associated with lower lung cancer incidence in men. Among individuals who were diagnosed with lung cancer, higher CRF was associated with reduced cancer mortality and longer survival time. These results support the protective benefits of higher CRF in the prevention of lung cancer outcomes. Eliminating low CRF as a risk factor would potentially prevent considerable lung cancer morbidity and mortality. 相似文献10.
Luke Hogarth Carl Payton Vaughan Nicholson Jemima Spathis Sean Tweedy Mark Connick Emma Beckman Peter Van de Vliet Brendan Burkett 《Journal of Science and Medicine in Sport》2019,22(5):526-531
Objectives
The International Paralympic Committee has mandated that International Sport Federations develop sport-specific classification systems that are evidence-based. This study examined the predictive and convergent validity of instrumented tapping tasks to classify motor coordination impairments in Para swimming.Design
Cross-sectional.Methods
Thirty non-disabled participants and twenty-one Para swimmers with brain injury completed several instrumented tapping tasks as an assessment of upper and lower limb motor coordination. Para swimmers also completed a maximal freestyle swim to obtain a performance measure. The predictive and convergent validity of instrumented tapping tasks was examined by establishing differences in test measures between participants with and without brain injury and defining the strength of association between test measures and maximal freestyle swim speed in Para swimmers, respectively.Results
Random forest successfully classified 96% of participants with and without brain injury using test measures derived from instrumented tapping tasks. Most test measures had moderate to high correlations (r = 0.54 to 0.72; p < 0.01) with maximal freestyle swim speed and collectively explained up to 72% of the variance in maximal freestyle swim performance in Para swimmers with brain injury.Conclusions
The results of this study evidence the predictive and convergent validity of instrumented tapping tasks to classify motor coordination impairments in Para swimmers with brain injury. These tests can be included in revised Para swimming classification to improve the objectivity and transparency in determining athlete eligibility and sport class for these Para athletes. 相似文献11.
Feng Pan Karl Smith Byrne Rema Ramakrishnan Manuela Ferreira Terence Dwyer Graeme Jones 《Journal of Science and Medicine in Sport》2019,22(4):444-449
Objectives
To describe the cross-sectional association between musculoskeletal pain at multiple sites and physical work capacity (PWC) and objectively measured physical activity (PA).Design
Observational study.Methods
Data from a subsample of the UK Biobank were utilised (n = 9856; mean age 58.5 years, mean body mass index 30.2 kg/m2, 62% female). PWC was measured by a bicycle ergometer and PA by an accelerometer. Pain experienced in hip, knee, back and neck/shoulder was collected by questionnaire. Linear regression modelling was used with adjustment for potential confounders to estimate the association between pain and PWC and PA.Results
Increase in number of painful sites was associated with lower PWC, moderate and vigorous PA and increased low intensity PA in a dose-response relationship (all p-values for trend ≤0.001) before and after adjustment for confounders. In site specific analyses, hip pain was associated with an increased low intensity PA (β 52.8 min/week, 95% CI 2.3–103.2) and reduced moderate PA (β ?50.1 min/week, 95% CI ?98.5 to ?1.8). Knee pain was only associated with vigorous PA (β ?5.7 min/week, 95% CI ?10.0 to ?1.3). Pain at neck/shoulder pain and back were not independently associated with PWC and PA.Conclusions
Greater number of painful sites is consistently associated with poorer PWC, increased low intensity PA and reduced moderate to vigorous PA. Clinicians should address the critical role of being physically active in managing chronic musculoskeletal pain and interventions targeting musculoskeletal pain may be needed to increase PA levels. 相似文献12.
Erin K. Howie Leo Ng Darren Beales Joanne A. McVeigh Leon M. Straker 《Journal of Science and Medicine in Sport》2019,22(4):456-461
Objectives
The purpose of this study was to identify early life factors that were associated with childhood and adolescent organized sport participation trajectories.Design
Participants were in the Raine Study, a pregnancy cohort in Western Australia recruited from 1989 to 1991.Methods
Three organized sport trajectories over ages 5–17 years were previously identified for girls (n = 824: consistent participators, dropouts, and non-participators in sport) and boys (n = 855: consistent participators, dropouts, joiners — those who joined sport in adolescence). Physical, psychological and social factors were measured from birth to age 5.Results
For girls and boys, children who were breastfed, were taller, did not have behavior problems, and attended childcare were more likely to consistently participate. Girls who had a previous injury (Relative risk ratio 1.55: 95% confidence interval 1.05, 2.29 vs never been injured) or who had parents who had worries about their child’s health (1.56: 1.00, 2.42 vs no worries) were more likely to be in the dropout trajectory. Boys born preterm (2.00, 2.06, 3.76 vs full-term), did not have a previous injury (0.72, 0.53, 0.97 those with injury vs never been injured), had more difficult temperament (1.63, 1.02, 2.60 vs easy temperament), and higher family dysfunction (1.49, 1.06, 2.08) were more likely to be in the dropout trajectory.Conclusions
Early life factors were associated with membership in sport trajectories. Physical, psychological, and social factors may serve as early warning signs for parents and practitioners that children may be at higher risk of dropping out of sports. 相似文献13.
Pontus Henriksson Marja H. Leppänen Hanna Henriksson Christine Delisle Nyström Cristina Cadenas-Sanchez Anna Ek Jonatan R. Ruiz Francisco B. Ortega Marie Löf 《Journal of Science and Medicine in Sport》2019,22(5):574-579
Objectives
Although physical fitness is considered a marker of health in youth, little is known whether physical fitness in pre-school age is related to later body composition. Thus, this study investigated (i) associations of physical fitness at 4.5 years of age with body composition 12 months later and (ii) whether improvements in physical fitness during the 12-month follow-up were associated with changes in body composition.Design
This study included 142 children, measured at 4.5 and 5.5 years, from the control group of the MINISTOP trial.Methods
Physical fitness (cardiorespiratory fitness, lower- and upper-body muscular strength and motor fitness) was measured using the PREFIT test battery. Body composition was assessed using air-displacement plethysmography.Results
In adjusted regression analyses, greater cardiorespiratory fitness, lower-body muscular strength and motor fitness at 4.5 years were associated with a lower fat mass index at 5.5 years (standardized β= ?0.182 to ?0.229, p ≤ 0.028). Conversely, greater cardiorespiratory fitness, lower- and upper-body muscular strength as well as motor fitness at 4.5 years of age were associated with a higher fat-free mass index (standardized β = 0.255–0.447, p ≤ 0.001). Furthermore, improvements in cardiorespiratory fitness, lower-body muscular strength and motor fitness during the 12-month follow-up period were associated with decreases in fat mass index and/or % fat mass.Conclusions
In conclusion, the results of this study provide evidence of the importance of physical fitness early in life. Nevertheless, further studies are needed in order to clarify the influence of physical fitness in the pre-school age with later health outcomes. 相似文献14.
Wen-Shiuan Shih Chueh-Hung Wu Tyng-Guey Wang 《Journal of Science and Medicine in Sport》2019,22(4):392-396
Objectives
Among symptomatic dancers, sonographic abnormalities are common. Whether asymptomatic dancers have any abnormalities remains unknown. Some dancers became cyanosis over distal feet after ballet training. The hemodynamic changes at the feet in ballet are not clearly understood.Design
Cross-sectional study.Methods
In 25 dancers and 14 non-dancers, B-mode ultrasonography was used to measure cross-sectional areas (CSA) of tendons of deep posterior compartment muscles. Doppler ultrasonography was used to measure peak velocity (Vpeak) of posterior tibial artery in three ankle postures: the neutral position, passively and forced actively plantar flexion (en pointe). The big toe oxygen saturation was recorded in neutral position and during 1-min en pointe. Single-leg standing heel rise test was performed to represent the muscle function.Results
The CSA of FHL was larger in dancers (0.26 cm2 [0.20, 0.30] vs 0.21 cm2 [0.17, 0.24], p < 0.01), while other tendons were not different (all p > 0.05). Higher Vpeak was recorded in passively plantar flexion than in neutral position (p < 0.01, in both groups). The blood flow was undetectable during en pointe, more frequently in dancers (54.9% vs 14.3%, p < 0.01). Oxygen saturation decreased during en pointe more prominently in dancers (85% [80, 90] vs 94% [84, 97], p < 0.01). There was no significant difference in muscle function.Conclusions
US showed the FHL tendon thickening and en pointe-related vascular compromise in pre-professional dancers, even when they are asymptomatic. 相似文献15.
Joseph M. Northey Kate L. Pumpa Clare Quinlan Ashley Ikin Kellie Toohey Disa J. Smee Ben Rattray 《Journal of Science and Medicine in Sport》2019,22(5):580-585
Objectives
The current study investigated the effects of two exercise interventions on cognitive function amongst breast cancer survivors.Design
Pilot randomised-controlled trial.Methods
Seventeen female cancer survivors (mean: 62.9 ± 7.8 years) were randomised into three groups: high-intensity interval training (HIIT, n = 6); moderate-intensity continuous training (MOD, n = 5); or wait-list control (CON, n = 6). The HIIT and MOD groups exercised on a cycle ergometer 3 days/week for 12-weeks. Primary outcomes were cognitive function assessments utilising CogState. Secondary outcomes were resting middle cerebral artery blood flow velocity, cerebrovascular reactivity and aerobic fitness (VO2peak). Data were analysed with General Linear Mixed Models and Cohen’s d effect sizes were calculated.Results
All 17 participants who were randomised were available for follow-up analysis and adherence was similar for HIIT and MOD (78.7 ± 13.2% vs 79.4 ± 12.0%; p = 0.93). Although there were no significant differences in the cognitive and cerebrovascular outcomes, HIIT produced moderate to large positive effects in comparison to MOD and CON for outcomes including episodic memory, working memory, executive function, cerebral blood flow and cerebrovascular reactivity. HIIT significantly increased VO2peak by 19.3% (d = 1.28) and MOD had a non-significant 5.6% (d = 0.72) increase, compared to CON which had a 2.6% decrease.Conclusions
This study provides preliminary evidence that HIIT may be an effective exercise intervention to improve cognitive performance, cerebrovascular function and aerobic fitness in breast cancer survivors. Considering the sample size is small, these results should be confirmed through larger clinical trials. 相似文献16.
Kimberley L. Way Rachelle N. Sultana Angelo Sabag Michael K. Baker Nathan A. Johnson 《Journal of Science and Medicine in Sport》2019,22(4):385-391
Objectives
Greater arterial stiffness and poor 24 h blood pressure (BP) are recognized as indicators of poor cardiovascular health. Evidence has shown that high intensity interval training (HIIT) may be a superior alternative to moderate intensity continuous training (MICT) for improving cardiovascular disease risk factors such as cardiorespiratory fitness and vascular function. However, there are limited data comparing the effect of HIIT to MICT on central arterial stiffness and/or 24 h BP response. The purpose of this study was to compare HIIT versus MICT on central arterial stiffness and 24 h BP outcomes by systematic review and meta-analysis.Design
A systematic review and meta-analysis was conducted.Methods
Eligible studies were exercise training interventions (≥4 weeks) that included both HIIT and MICT and reported central arterial stiffness, as measured by pulse wave velocity and augmentation index and/or 24 h BP outcome measures.Results
HIIT was found to be superior to MICT for reducing night-time diastolic BP (ES: ?0.456, 95% CI: ?0.826 to ?0.086 mmHg; P = 0.016). A near-significant greater reduction in daytime systolic (ES: ?0.349, 95% CI: ?0.740 to 0.041 mmHg; p = 0.079) and diastolic BP was observed with HIIT compared to MICT (ES: ?0.349, 95% CI: ?0.717 to 0.020 mmHg; p = 0.063). No significant difference was found for other BP responses or arterial stiffness outcomes.Conclusions
HIIT leads to a superior reduction in night-time diastolic BP compared to MICT. Furthermore, a near-significant greater reduction in daytime BP was found with HIIT compared to MICT. No significant difference was observed for changes to central arterial stiffness between HIIT and MICT. 相似文献17.
Jonathan M.D. Staynor Sean D. Byrne Jacqueline A. Alderson Cyril J. Donnelly 《Journal of Science and Medicine in Sport》2019,22(4):420-424
Objectives
Appropriate statistical analysis of clustered data necessitates accounting for within-participant effects to ensure results are repeatable and translatable to real-world applications. This study aimed to compare statistical output and injury risk interpretation differences from two statistical regression models built from a clinical movement sidestepping database. A “naïve” regression model, which does not account for within-participant effects, was compared with an appropriately applied mixed effects model.Design
Comparative study.Methods
Three-dimensional unplanned sidestepping joint angle data (trunk, hip, and knee) from 35 males (112 observations) were used to model peak knee valgus moments and anterior cruciate ligament injury risk during the impact phase of stance. Both statistical models were cross-validated using a k-fold analysis.Results
The naïve regression returned inflated goodness of fit statistics (R2 = 0.50), which was evident following cross-validation (predicted R2 = 0.43). Following cross-validation, the mixed effects model (predicted R2 = 0.40) explained a similar amount of variance, despite containing three less predictors. The naïve model produced inaccurate parameter estimates, overestimating the effects of certain kinematic parameters by as much as 79 %.Conclusions
A regression model naïvely applied to clustered observations of sidestepping data resulted in erroneous parameter estimates and goodness of fit statistics which have the potential to mislead future research and real-world applications. It is important for sport and clinical scientists to use statistically appropriate mixed effects models when modelling clustered motion capture data for injury biomechanics research to protect the translatability of the findings. 相似文献18.
Cassandra S. Thompson Claire E. Hiller Siobhan M. Schabrun 《Journal of Science and Medicine in Sport》2019,22(4):425-429
Objectives
To compare soleus spinal reflex excitability, presynaptic inhibition and recurrent inhibition between chronic ankle instability (CAI), acute Lateral Ankle Sprain coper (LAS-coper) and healthy populations. The relationship between spinal reflex excitability and pain and perceived instability in people with CAI was also examined.Design
Cross-sectional laboratory experiment.Methods
Twelve individuals with CAI, twelve ‘copers’ and twelve healthy age, limb and gender-matched controls participated. Soleus H-reflex recruitment curves, pre-synaptic excitability and recurrent inhibition of the spinal-reflex pathway were examined during static double- and single-leg stance. Reporting of pain and perceived instability were used to perform a regression analysis on measures of soleus spinal excitability in people with CAI, LAS-coper and healthy controls.Results
Soleus spinal reflex excitability was greater during single-leg stance in CAI compared to healthy and coper individuals (p = <0.001). Pre-synaptic inhibition was three-times less in CAI participants compared to both healthy controls and copers (p = <0.001). There were no differences between healthy and coper participants in spinal-level measures of sensorimotor control. Reports of pain explained 15–16% of the variance in soleus spinal reflex excitability and presynaptic inhibition during single and double-leg stance, while perceived instability explained 20% of the variance in spinal reflex during single leg stance only.Conclusions
CAI participants presented with an inability to suppress soleus spinal reflexes during tasks with increased postural threat; likely due to disinhibition of pre-synaptic mechanisms. Pain and perceived instability may contribute to changes in spinal-level sensorimotor control in CAI. 相似文献19.
Ida J. Berglund Sara E. Sørås Bård E. Relling Kari M. Lundgren Ida A. Kiel Trine Moholdt 《Journal of Science and Medicine in Sport》2019,22(5):607-610
Objectives
It is suggested that individuals will not reach their heart rate maximum (HRmax) at an incremental cardiorespiratory fitness (CRF) test and commonly five beats per minute (bpm) are added to the highest heart rate (HR) reached. To our knowledge, there is not sufficient data justifying such estimation. Our aim was to assess whether individuals reached HRmax in an incremental CRF test to exhaustion.Design and methods
Fifty-one males and 57 females (aged 22–70 years) completed both an incremental CRF test (gradual increase in speed and/or inclination until volitional exhaustion) and a test designed to reach HRmax (with repeated work bouts at high intensity before maximal exertion) ≥48 h apart. We investigated the relationship between the highest HR in the two tests using hierarchical linear regression analysis, with HRmax from the HRmax test as a dependent variable, and the highest HR reached at the CRF test (HRcrf), whether maximum oxygen uptake was reached on the CRF test, CRF, sex and age as independent variables.Results
HRmax was 2.2 (95% confidence interval, 1.5–2.9) bpm higher in the test designed to reach HRmax than in the CRF test (p < 0.001). Only HRcrf significantly predicted HRmax, with no contribution of the other variables in the model. HRmax was predicted from the highest HR reached in an incremental CRF test by multiplying HRcrf with 0.967, and adding 8.197 (HRmax = 8.197 + [0.967 × HRcrf]) beats/min.Conclusion
Non-athletes reached close to HRmax in a standard CRF test. 相似文献20.
Andrew Murray Alec Buttfield Andrew Simpkin John Sproule Anthony P. Turner 《Journal of Science and Medicine in Sport》2019,22(4):488-493
