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1.
Work ; 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38552128

ABSTRACT

BACKGROUND: Firefighting is recognised as a physically demanding occupation involving exposure to hazardous environments and activities. An aging workforce combined with the age-related decline in physical fitness may result in increased future workers' compensation expenditure for fire service organisations. OBJECTIVE: The objective of this research was to investigate the costs associated with musculoskeletal sprain and strain injury and the impacts of age and injury location on Workers' Compensation claims submitted by professional urban firefighters. METHODS: Claim rates, direct costs, and days lost were extracted from a professional Fire Service organisation's workers' compensation claim database for financial years between 2011 to 2018. RESULTS: The mean cost per claim increased with age, with a mean claim cost of the 60-70-year-old group over 10 times more than the 20-29-year-old group. The mean days lost per claim were also higher for claims submitted by firefighters aged over 50. CONCLUSIONS: Older firefighters miss more workdays when injured and are associated with increased claims costs, particularly those in the 60-70-year group. With an aging workforce, Fire Service organisations must implement appropriate management and prevention strategies to reduce the potential risks associated with an aging workforce.

2.
J Strength Cond Res ; 37(11): e601-e608, 2023 Nov 01.
Article in English | MEDLINE | ID: mdl-37883408

ABSTRACT

ABSTRACT: Redshaw, AS, Carrick-Ranson, G, Bennett, H, Norton, KI, and Walker, A. Effect of aging on movement quality in Australian urban firefighters. J Strength Cond Res 37(11): e601-e608, 2023-Adequate levels of movement quality (MQ) are required to safely perform occupational tasks in physically demanding and hazardous professions such as firefighting. Although it is well established that MQ deteriorates with age in population studies, there is conflicting evidence in older tactical populations. This study sought to examine the relationship between age and MQ in Australian urban firefighters. The impact of physical activity, injury history, and body mass index on MQ were also explored. The MQ of 324 professional Australian urban firefighters was assessed using MovementSCREEN MQ assessment tool. Scores of whole-body MQ ranged from 35.3 to 82.6 (0-100 scale), with a mean score of 59.2 ± 10.0. There was a moderate, negative association between MQ and age (r = -0.500; p ≤ 0.001), with those older than 50 years of age having significantly lower scores of MQ than their younger counterparts (p ≤ 0.001). Secondary analysis found that higher body mass index (r = -0.285; p ≤ 0.001), lower habitual physical activity levels (r = 0.165; p ≤ 0.003), and the presence of any musculoskeletal injury in the previous 12 months (p = 0.016) had significant negative effects on composite MQ. Firefighters older than 50, obese, and engaging in low levels of physical activity should be considered a high priority for functional strength training interventions to maintain adequate MQ throughout their careers.


Subject(s)
Firefighters , Resistance Training , Humans , Aged , Australia , Aging , Body Mass Index , Movement
3.
JAMA Netw Open ; 6(8): e2328633, 2023 08 01.
Article in English | MEDLINE | ID: mdl-37566413

ABSTRACT

Importance: Concussions are common in sports. Return-to-play protocols can be enhanced by objective biometrics. Objective: To characterize temporal changes of headpulse, a digital biometric, in athletes with sports-related concussion; to explore the association of unstructured physical activity with headpulse changes. Design, Setting, and Participants: This cohort study included headpulse measurements from players in the highest level of amateur Australian Rules Football in South Australia. Analysis included feasibility and validation phases, with the feasibility cohort recruited between August 5, 2021, and September 10, 2021, and the validation cohort recruited between May 5, 2022, and September 3, 2022. Data were analyzed October 2022 through January 2023. Interventions: Cranial accelerometry detected micromovements of the head following cardiac contraction (what we have described as "headpulse"). Headpulse was serially recorded for 1 month in concussed individuals. Main Outcomes and Measures: Headpulse waveforms underwent frequency transformation analysis per prespecified algorithm. Result Z scores were calculated. Headpulse Z scores exceeding 2 (2 SDs from control means) met an abnormality threshold. Headpulse sensitivity, timing, and duration of change were determined. Results: A total of 59 control and 43 concussed individuals (44 total concussions; 1 control also concussed, 1 concussed individual injured twice) provided headpulse measurements. The feasibility cohort (all male) included 17 control (median [IQR] age, 23 [19-28] years) and 15 concussed individuals (median [IQR] age, 21 [19-23] years). The validation cohort included 25 female (median [IQR] age, 21 [20-22] years) and 17 male (median [IQR] age, 26 [23-29] years) control individuals, and 8 female (median [IQR] age, 28 [20-31] years) and 20 male (median [IQR] age, 21 [19-23] years) concussed individuals. Headpulse reached abnormality threshold in 26 of 32 concussed individuals (81%; 9% on day 0, 50% by day 2, 90% by day 14). Headpulse alterations lasted 14 days longer than symptoms and were exacerbated by return-to-play or unsupervised physical activity. Conclusions and Relevance: In this study of 101 amateur Australian Rules Football athletes, the digital headpulse biometric was evaluated in 44 sports-related concussions. Compared with controls, new headpulse changes occurred after concussion; this objective metric may complement return-to-play protocols.


Subject(s)
Brain Concussion , Humans , Male , Female , Young Adult , Adult , Cohort Studies , Australia/epidemiology , Brain Concussion/diagnosis , Athletes , Biometry
4.
J Pharmacol Toxicol Methods ; 121: 107266, 2023.
Article in English | MEDLINE | ID: mdl-36963703

ABSTRACT

INTRODUCTION: Characterization of the incidence of spontaneous arrhythmias to identify possible drug-related effects is often an important part of the analysis in safety pharmacology studies using telemetry. METHODS: A retrospective analysis in non-clinical species with and without telemetry transmitters was conducted. Electrocardiograms (24 h) from male and female beagle dogs (n = 131), Göttingen minipigs (n = 108) and cynomolgus non-human primates (NHP; n = 78) were analyzed. RESULTS: Ventricular tachycardia (VT) was observed in 3% of the dogs but was absent in minipigs and NHPs. Ventricular fibrillation (VF) was not observed in the 3 species. Ventricular premature beats (VPBs) were more frequent during daytime and atrioventricular blocks (AVBs) were more frequent at night in all species. A limited number of animals exhibited a high arrhythmia frequency and there was no correlation between animals with higher frequency of an arrhythmia type and the frequency of other arrythmias in the same animals. Clinical chemistry or hematology parameters were not different with or without telemetry devices. NHP with a transmural left ventricular pressure (LVP) catheter exhibited a greater incidence of VPBs and PJCs compared to telemetry animals without LVP. DISCUSSION: All species were similar with regards to the frequency of ventricular ectopic beats (26-46%) while the dog seemed to have more frequent junctional complexes and AVB compared to NHP and minipigs. Arrhythmia screening may be considered during pre-study evaluations, to exclude animals with abnormally high arrhythmia incidence.


Subject(s)
Arrhythmias, Cardiac , Telemetry , Animals , Dogs , Swine , Male , Female , Swine, Miniature , Incidence , Retrospective Studies , Electrocardiography
5.
Sci Rep ; 12(1): 19803, 2022 11 17.
Article in English | MEDLINE | ID: mdl-36396735

ABSTRACT

Landscape evolution is driven by tectonics, climate and surface denudation. In New Zealand, tectonics and steep climatic gradients cause a dynamic landscape with intense chemical weathering, rapid soil formation, and high soil losses. In this study, soil, and elemental redistribution along two adjacent hillslopes in East Otago, New Zealand, having different landscape settings (ridge versus valley) are compared to identify soil weathering and erosion dynamics. Fallout radionuclides (239+240Pu) show that over the last ~ 60 years, average soil erosion rates in the valley (~ 260 [t km-2 year-1]) are low compared to the ridge (~ 990 [t km-2 year-1]). The ridge yields up to 26% lower soil weathering intensity than the topographical-protected valley. The lowest soil weathering intensity is found at both hilltop positions, where tors (residual rocks) are present and partially disintegrate. The soil weathering intensity increases with distance from tors, suggesting that tors rejuvenate the chemical weathering signature at the hilltop positions with fresh material. The inversed and decreasing weathering degree with all soil depth indicates that the fresh mineral contribution must be higher at the soil surface than at the bedrock weathering front. Higher erosion rates at the exposed ridge may be partially attributed to wind, consistent with rock abrasion of tors, and low local river sediment yields (56 [t km-2 year-1]). Thus, the East Otago spatial patterns of soil chemistry and erosion are governed by tor degradation and topographic exposure.


Subject(s)
Soil , Weather , New Zealand , Rivers
6.
Int J Sports Physiol Perform ; 17(2): 170-175, 2022 02 01.
Article in English | MEDLINE | ID: mdl-34560664

ABSTRACT

PURPOSE: Modeling intermittent work capacity is an exciting development to the critical power model with many possible applications across elite sport. With the Skiba 2 model validated using subelite participants, an adjustment to the model's recovery rate has been proposed for use in elite cyclists (Bartram adjustment). The team pursuit provides an intermittent supramaximal event with which to validate the modeling of W' in this population. METHODS: Team pursuit data of 6 elite cyclists competing for Australia at a Track World Cup were solved for end W' values using both the Skiba 2 model and the Bartram adjustment. Each model's success was evaluated by its ability to approximate end W' values of 0 kJ, as well as a count of races modeled to within a predetermined error threshold of ±1.840 kJ. RESULTS: On average, using the Skiba 2 model found end W' values different from zero (P = .007; mean ± 95% confidence limit, -2.7 ± 2.0 kJ), with 3 out of 8 cases ending within the predetermined error threshold. Using the Bartram adjustment on average resulted in end W' values that were not different from zero (P = .626; mean ± 95% confidence limit, 0.5 ± 2.5 kJ), with 4 out of 8 cases falling within the predetermined error threshold. CONCLUSIONS: On average, the Bartram adjustment was an improvement to modeling intermittent work capacity in elite cyclists, with the Skiba 2 model underestimating the rate of W' recovery. In the specific context of modeling team pursuit races, all models were too variable for effective use; hence, individual recovery rates should be explored beyond population-specific rates.


Subject(s)
Bicycling , Soccer , Australia , Exercise Test , Humans , Oxygen Consumption
7.
Sports Med Open ; 7(1): 28, 2021 Apr 28.
Article in English | MEDLINE | ID: mdl-33913061

ABSTRACT

BACKGROUND: There is extensive research investigating the match demands of players in the Australian Football League (AFL). OBJECTIVE: This systematic literature review and meta-regression sought to analyse the evolution of in-game demands in AFL matches from 2005 to 2017, focusing on the relationship between volume and intensity. METHODS: A systematic search of Ovid MEDLINE, Embase, Emcare, Scopus, SPORTDiscus, and Cochrane Library databases was conducted. Included studies examined the physical demands of AFL matches utilising global positioning system (GPS) technology. Meta-regression analysed the shift in reported volume (total distance and total match time) and intensity (metres per minute [m.min-1], sprint duration and acceleration) metrics for overall changes, across quarters and positional groups (forwards, nomadics and defenders) from 2005 to 2017 inclusive and for each year between 2005 and 2007, 2007 and 2010, 2010 and 2012, and 2012 and 2015/2017 breakpoints. RESULTS: Distance (p = 0.094), m.min-1 (p = 0.494), match time (p = 0.591), time over 18 km·h-1 (p = 0.271), and number of accelerations greater than 4 km·h-1 (p = 0.498) and 10 km·h-1 (p = 0.335) in 1 s did not change from 2005 to 2017. From 2005 to 2007 volume decreased (- 6.10 min of match time; p = 0.010) and intensity increased (6.8 m.min-1 increase; p = 0.023). Volume and intensity increased from 2007 to 2010, evidenced by increases in total distance (302 m; p = 0.039), time over 18 km·h-1 (0.31 min; p = 0.005), and number of accelerations greater than 4 km·h-1 (41.1; p = 0.004) and 10 km·h-1 (3.6; p = 0.005) in 1 s. From 2010 to 2012, intensity decreased, evidenced by reductions in metres per minute (- 4.3; p = 0.022), time over 18 km·h-1 (- 0.93 min; p < 0.001), and number of accelerations greater than 4 km·h-1 (- 104.4; p < 0.001) and 10 km·h-1 (- 8.3; p < 0.001) in 1 s, whilst volume stabilised with no changes in distance (p = 0.068) and match time (p = 0.443). From 2012 to 2015/2017 volume remained stable and intensity increased with time over 18 km·h-1 (0.27 min; p = 0.008) and number of accelerations greater than 4 km·h-1 (31.6; p = 0.016) in 1 s increasing. CONCLUSIONS: Changes in volume and intensity of AFL match demands are defined by discrete periods from 2007 to 2010 and 2010 to 2012. The interaction of rule and interpretation changes and coaching strategies play a major role in these evolutionary changes. In turn, modified game styles impact player game demands, training, and selection priorities. Standardisation and uniformity of GPS data reporting is recommended due to inconsistencies in the literature.

8.
J Sports Sci Med ; 19(3): 508-516, 2020 09.
Article in English | MEDLINE | ID: mdl-32874103

ABSTRACT

The aim of this investigation was to compare the changes in endurance running performance and physiological variables after a four-week period of high intensity interval training (HIIT) in either running or cycling in female athletes. Fourteen recreational female runners (age = 42 10 yr, height = 1.67 0.06 m, body mass = 61.6 10.4 kg, body mass index (BMI) = 22.2 3.4 kg.m-2) were randomly allocated to one of two HIIT training groups: running (HIITrun) or cycling (HIITbike). Each group performed two HIIT sessions per week for 4 weeks, which consisted of 6 x 2 min at 95% of maximal heart rate (HRmax) and 4 x 1 min all out efforts. Maximal oxygen consumption (VO2max) in treadmill running increased significantly after the HIITrun (p < 0.01, ES = 0.6) but remained unchanged in HIITbike. However, HIITbike improved average velocity in a 10 km running time trial (TTrun) (p < 0.05, ES = -0.4), whereas, no changes were found for the HIITrun group. Analysing the first and last HIIT sessions, for HIITrun only the average rate of perceived exertion (RPEav) increased significantly, whereas, performance variables such as average heart rate (HRav) and average pace (paceav) remained unchanged. HIITbike enhanced significantly the average speed of HIIT sets (speedav) and the peak power output (PPO) of the session, as well as, the RPEav and delayed onset muscle soreness immediately after HIIT session (DOMSpost) were increased significantly. A regime of HIIT in cycling may evoke increases in female recreational runners' power, which may be related with improvements in a 10 km TTrun independent of changes in aerobic capacity. This may be advantageous in order to avoid overuse running related injuries.


Subject(s)
Bicycling/physiology , High-Intensity Interval Training/methods , Physical Endurance/physiology , Running/physiology , Adult , Creatine Kinase/blood , Female , Heart Rate , Humans , Lactic Acid/blood , Middle Aged , Muscle Fatigue/physiology , Myalgia/metabolism , Myalgia/physiopathology , Oxygen Consumption , Perception/physiology , Physical Exertion/physiology
10.
J Sports Sci Med ; 19(1): 78-83, 2020 03.
Article in English | MEDLINE | ID: mdl-32132830

ABSTRACT

The aim of this study was to evaluate the influence of contextual factors on game styles in professional soccer. Interactions between styles and different playing venues, opposition quality, total match goals, and competing styles, were investigated using logistic regression and odds ratios. Game styles were characterised using the moments of play framework where three distinct styles have been identified: Style 1 - moderate strength in defence; Style 2 - dominance in transition, and Style 3 - strength in attacking phases of play. Results revealed that when playing at home against teams identified by Style 1, teams were more likely to play Style 2 (p < 0.05) or Style 3 (p < 0.001). Against top 10 opposition, teams were less likely to play Style 3 compared to either Style 1 (p < 0.001) or Style 2 (p < 0.001). Regardless of venue, teams were more likely to play Style 3 against bottom 10 sides compared to either Style 1 (p < 0.001) or Style 2 (p < 0.001), suggesting a hierarchical order between contextual factors. Competing game styles significantly impacted total match goals scored, whilst match results were also influenced by game style combinations. Overall, this study showed the significant effects of various contextual variables on game styles played by teams in the EPL.


Subject(s)
Athletic Performance/physiology , Competitive Behavior/physiology , Soccer/physiology , England , Humans , Motor Skills/physiology
11.
Int J Sports Physiol Perform ; 15(1): 68-72, 2020 Jan 01.
Article in English | MEDLINE | ID: mdl-31034296

ABSTRACT

PURPOSE: To determine the typical variation of variables from a countermovement jump (CMJ) test and a submaximal run test (SRT), along with comparing the sensitivity of each test for the detection of practically important changes within high-performance Australian rules football players. METHODS: A total of 23 professional and semiprofessional Australian rules football players performed 6 CMJs and three 8-second 50-m runs every 30 seconds (SRT), 7 days apart. Absolute and trial-to-trial reliability was represented as a coefficient of variation, CV (±90% confidence intervals). Test-retest reliability was examined using the magnitude of the difference (effect size [±90% confidence interval]) from week 1 to week 2. The smallest worthwhile change was calculated as 0.25 × SD. RESULTS: Good reliability (CVs = 6.6%-9.3%) was determined for all variables except eccentric displacement (CV = 12.8%), with no clear changes observed in any variables between week 1 and week 2. All variables from the SRT possessed a CV less than smallest worthwhile change, indicating an ability to detect practically important changes in performance. Only peak velocity from the CMJ test possessed a CV less than smallest worthwhile change, exhibiting a limitation of this test in detecting practically meaningful changes within this environment. CONCLUSIONS: The results suggest that while all variables possess acceptable reliability, a SRT might offer to be a more sensitive monitoring tool than a CMJ test within high-performance Australian rules football, due to its greater ability for detecting practically important changes in performance.

12.
Int J Sports Phys Ther ; 14(3): 424-435, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31681501

ABSTRACT

BACKGROUND/PURPOSE: Movement quality is commonly assessed to identify movement limitations and guide exercise prescription. Rapid growth in the movement assessment landscape has led to the development and utilization of various movement quality assessments, many without reliability estimates. MovementSCREEN is a novel, tablet-based, video-recorded movement assessment tool, currently without published reliability information. Therefore, the purpose of this study was to determine the intra and inter-rater reliability of the MovementSCREEN, including the impact of rater experience, and provide estimates of measurement error and minimal detectable change. STUDY DESIGN: Cross-sectional design; reliability study. METHODS: Thirty healthy young adults (14M:16F, mean age 28.4 yrs, SD 9.1) were video recorded completing the nine MovementSCREEN assessment items on two occasions, two weeks apart. Each individual movement was assessed against objective scoring criteria (component items: yes/no) and using a 100-point sliding scale. To create an overall score for each movement, the scale score is weighted against the objective items to provide a score out of 100. At the completion of all nine individual movements, a mean composite score of movement quality is also established (0-100). The first recording was scored twice by two expert and two novice assessors to investigate inter- and intra-rater reliability. The second recording was scored by one expert assessor to investigate within-subject error. Inter- and intra-rater reliability was calculated using intraclass correlation coefficients (ICCs) and Kappa statistics. The standard error of measurement (SEM), and minimal detectable change (MDC95) for the overall score for each movement, and the composite score of movement quality, were calculated. RESULTS: Intra-rater reliability for the component items ranged from κ = 0.619 - 1.000 (substantial to near perfect agreement) and 0.233 - 1.000 (slight to near perfect agreement) for expert and novice assessors, respectively. The ICCs for the overall movement quality scores for each individual movement ranged from 0.707 - 0.952 (fair to high) in expert and 0.502 - 0.958 (poor to high) in novice assessors. Inter-rater agreement for the component items between expert assessors ranged from κ = 0.242 - 1.000 (slight to almost perfect agreement), while for novice assessors ranged from 0.103 - 1.000 (less than chance to almost perfect agreement). ICCs for the overall scores for each individual movement from expert and novice assessors ranged from 0.294 - 0.851 (poor to good) and 0.249 - 0.775 (poor to fair), respectively. The SEM for the composite score was 2 points, while the MDC95 was 6 points, with an ICC 0.901. CONCLUSIONS: The MovementSCREEN can assess movement quality with fair to high reliability on a test-retest basis when used by experienced assessors, although reliability scores decrease in novice assessors. Comparisons between assessors involve greater error. Therefore, the training of inexperienced assessors is recommended to improve reliability. LEVEL OF EVIDENCE: 2b.

13.
J Sports Sci ; 37(24): 2806-2817, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31500505

ABSTRACT

The aim of this trial was to compare an eight-week individual movement quality versus traditional resistance training intervention on movement quality and physical performance. Forty-six trained adults were randomised to a movement quality-focused training (MQ) or a traditional resistance training (TRAD) group, and performed two individualised training sessions per week, for 8 weeks. Session-RPE (sRPE) was obtained from each session. Measures of movement quality (MovementSCREEN and Functional Movement Screen (FMS)) and physical performance were performed pre- and post-intervention. All measures improved significantly in both groups (3-14.5%, p = <0.005). The between-group difference in MovementSCREEN composite score was not statistically significant (0.3, 95% CI -3.4, 4.1, p = 0.852). However, change in FMS composite was significantly greater in MQ (1.3, 95% CI 0.8, 1.8, p < 0.001). There were no significant between-group differences in physical performance (p = 0.060-0.960). The mean sRPE was significantly lower in MQ (5.25, SD 1.2) compared to TRAD (6.6 SD 1.0, p = <0.001). Thus, although movement quality scores were not distinctly greater in the MQ group, a movement quality specific intervention caused comparable improvements in physical performance compared to traditional resistance training but at lower perceived training intensity.


Subject(s)
Motor Skills , Movement , Physical Functional Performance , Resistance Training , Adult , Female , Humans , Male , Muscle Strength , Muscle, Skeletal/physiology , Young Adult
14.
J Sports Med Phys Fitness ; 59(8): 1328-1338, 2019 Aug.
Article in English | MEDLINE | ID: mdl-30758168

ABSTRACT

INTRODUCTION: With the underlying mechanisms of fatigue shown to be task-specific, gaining an understanding of changes within the running profile due to fatigue may provide a greater task-specific method for monitoring neuromuscular fatigue (NMF) in elite team sport athletes. This review aimed to identify, review and summarize the literature to understand the effects of fatigue on the running profile of elite team sport athletes. EVIDENCE ACQUISITION: MEDLINE, SPORTDiscus, EMBASE and CINAHL were searched. To manage heterogeneity in athlete characteristics and sport demands, studies were limited to elite male field/court team sports, in which changes in running, gait or stride characteristics were assessed. EVIDENCE SYNTHESIS: Thirteen studies were included in the analysis with changes in sprint time, kinematic variables; contact time, center of mass vertical displacement and vertical stiffness, GPS accelerometer vector variables; z and y, and mechanical parameters; velocity and V0, all shown to be sensitive measures of fatigue. Due to having at least three sets of data points, meta-analysis was run for sprint time, with results showing a significant increase immediately postexercise (effect size [ES]±95% confidence interval [CI]; 1.67±1.61, P=0.04), but no change 24 hours postexercise (ES±95% CI; 0.93±3.21, P=0.57). CONCLUSIONS: The findings indicate that fatigue has a negative impact on the running profile in elite team sport athletes, offering an alternative task-specific measure of monitoring NMF in this population. However, due to large discrepancies in protocols, future research is required to allow greater uniformity in variables and methods.


Subject(s)
Running/physiology , Athletic Performance/physiology , Biomechanical Phenomena , Fatigue/physiopathology , Humans , Male
15.
Sports Med ; 49(1): 41-55, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30390202

ABSTRACT

OBJECTIVE: To estimate international and national temporal trends in the cardiorespiratory fitness (CRF) of adults, and to examine relationships between trends in CRF and trends in health-related, socioeconomic, and environmental indicators. METHODS: Data were obtained from a systematic search of studies that explicitly reported temporal trends in the CRF of apparently healthy adults aged 18-59 years. Sample-weighted temporal trends were estimated using best-fitting regression models relating the year of testing to mean CRF. Post-stratified population-weighted mean changes in percent and standardized CRF were estimated. Pearson's correlations were used to describe associations between linear trends in CRF and linear trends in health-related, socioeconomic, and environmental indicators. RESULTS: 2,525,827 adults representing eight high- and upper-middle-income countries between 1967 and 2016 collectively showed a moderate decline of 7.7% (95% CI - 8.4 to - 7.0) or 1.6% per decade (95% CI - 1.7 to - 1.5). Internationally, CRF improved in the 1960s and 1970s, and progressively declined at an increasing rate thereafter. Declines were larger for men than for women, and for young adults (< 40 years) than for middle-aged adults (≥ 40 years). All countries experienced declines in CRF with a very strong negative correlation between CRF trends and obesity trends. CONCLUSIONS: There has been a meaningful decline in the CRF of adults since 1980, which has progressively increased in magnitude over time, suggestive of a corresponding decline in population health. Continuous national and international surveillance systems are needed in order to monitor health and fitness trends, especially among low- and middle-income countries for which data do not currently exist. PROSPERO registration number: CRD42013003678.


Subject(s)
Cardiorespiratory Fitness , Global Health/trends , Adolescent , Adult , Female , Health Status , Humans , Male , Middle Aged , Young Adult
16.
Int J Sports Physiol Perform ; 14(2): 239-245, 2019 Feb 01.
Article in English | MEDLINE | ID: mdl-30080432

ABSTRACT

PURPOSE: To investigate changes in physiological and performance variables in triathletes following a 4-wk period of reduced training volume and increased training intensity. METHODS: Sixteen moderately trained triathletes were randomly allocated to 2 groups: a control (CON) group, which followed their usual training, or a high-intensity interval training (HIIT) group, which completed 2 HIIT sessions per week during 4 wk of reduced training volume Results: Maximal oxygen consumption (VO2max) increased significantly in the HIIT group (P = .03, d = 0.5) but remained unchanged in the CON group. Cycling power at first and second ventilatory thresholds increased significantly in the HIIT subjects (P = .03, d = 1.0) and was unchanged in the CON participants (P = .57). During the simulated triathlon test, pretest-posttest cycling times and average power were unchanged in both groups (P > .05). No significant interactive effects between groups were observed for running time (P = .50). CONCLUSION: After a 4-wk HIIT program, VO2max and power at first and second ventilatory thresholds were found to have increased significantly while cycling and running performance were unchanged, despite an overall reduction in training time. In the present study, performance was only shown to improve with usual (high-volume) training. Summarizing, in order to improve running or cycling performances, high-volume training programs are highly recommended.


Subject(s)
Athletic Performance/physiology , High-Intensity Interval Training , Physical Endurance , Adult , Athletes , Bicycling/physiology , Female , Humans , Male , Middle Aged , Oxygen Consumption , Physical Fitness , Running/physiology , Swimming/physiology
17.
Int J Sports Physiol Perform ; 14(5): 598-605, 2019 May 01.
Article in English | MEDLINE | ID: mdl-30427228

ABSTRACT

Purpose: To compare the sensitivity of a submaximal run test (SRT) with a countermovement-jump test (CMJ) to provide an alternative method of measuring neuromuscular fatigue (NMF) in high-performance sport. Methods: A total of 23 professional and semiprofessional Australian rules football players performed an SRT and CMJ test prematch and 48 and 96 h postmatch. Variables from accelerometers recorded during the SRT were player load 1D up (vertical vector), player load 1D side (mediolateral vector), and player load 1D forward (anteroposterior vector). Meaningful difference was examined through magnitude-based inferences (effect size [ES]), with reliability assessed as typical error of measurements expressed as coefficient of variance. Results: A small decrease in CMJ height, ES -0.43 ± 0.39 (likely), was observed 48 h postmatch before returning to baseline 96 h postmatch. This was accompanied by corresponding moderate decreases in the SRT variables player load 1D up, ES -0.60 ± 0.51 (likely), and player load 1D side, ES -0.74 ± 0.57 (likely), 48 h postmatch before also returning to prematch baseline. Conclusion: The results suggest that in the presence of NMF, players use an alternative running profile to produce the same external output (ie, time). This indicates that changes in accelerometer variables during an SRT can be used as an alternative method of measuring NMF in high-performance Australian rules football and provides a flexible option for monitoring changes in the recovery phase postmatch.


Subject(s)
Accelerometry/methods , Exercise Test/methods , Fatigue/diagnosis , Adolescent , Adult , Football , Humans , Male , Muscle Fatigue , Plyometric Exercise , Reproducibility of Results , Running , Young Adult
18.
Sports Med ; 48(11): 2517-2548, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30141022

ABSTRACT

BACKGROUND: Intensified training is important for inducing adaptations to improve athletic performance, but detrimental performance effects can occur if prescribed inappropriately. Monitoring biomarker responses to training may inform changes in training load to optimize performance. OBJECTIVE: This systematic review and meta-analysis aimed to identify biomarkers associated with altered exercise performance following intensified training. METHODS: Embase, MEDLINE, CINAHL, Scopus and SPORTDiscus were searched up until September 2017. Included articles were peer reviewed and reported on biomarkers collected at rest in well-trained male athletes before and after periods of intensified training. RESULTS: The full text of 161 articles was reviewed, with 59 included (708 participants) and 42 (550 participants) meta-analysed. In total, 118 biomarkers were evaluated, with most being cellular communication and immunity markers (n = 54). Studies most frequently measured cortisol (n = 34), creatine kinase (n = 25) and testosterone (n = 20). Many studies reported decreased immune cell counts following intensified training, irrespective of performance. Moreover, reduced performance was associated with a decrease in neutrophils (d = - 0.57; 95% confidence interval (CI) - 1.07 to - 0.07) and glutamine (d = - 0.37; 95% CI - 0.43 to - 0.31) and an increase in urea concentration (d = 0.80; 95% CI 0.30 to 1.30). In contrast, increased performance was associated with an increased testosterone:cortisol ratio (d = 0.89; 95% CI 0.54 to 1.24). All remaining biomarkers showed no consistent patterns of change with performance. CONCLUSIONS: Many biomarkers were altered with intensified training but not in a manner related to changes in exercise performance. Neutrophils, glutamine, urea and the testosterone:cortisol ratio exhibited some evidence of directional changes that corresponded with performance changes therefore indicating potential to track performance. Additional investigations of the potential for these markers to track altered performance are warranted.


Subject(s)
Athletes , Athletic Performance/physiology , Biomarkers/analysis , Exercise , Creatine Kinase/analysis , Glutamine/analysis , Humans , Hydrocortisone/analysis , Lymphocyte Count , Male , Neutrophils , Testosterone/analysis , Urea/analysis
19.
PLoS One ; 13(6): e0199836, 2018.
Article in English | MEDLINE | ID: mdl-29944718

ABSTRACT

OBJECTIVES: To investigate the levels of agreement between self-reported responses to the Adult Pre-exercise Screening System (APSS) questionnaire using online versus face-to-face (F2F) modalities. DESIGN: Convenience sample of adults completing a pre-exercise screening questionnaire using different modalities. METHODS: Adult volunteers (n = 94) were recruited to complete the APSS using both online and F2F modalities. Participants were provided a URL link to an online APSS questionnaire then followed-up the next day in a F2F interview. Objective health risk factors were also measured. Comparisons between responses were undertaken using kappa and correlation statistics to determine levels of agreement. RESULTS: The levels of agreement between online versus F2F responses for the seven compulsory Stage 1 questions (known diseases and signs and/or symptoms of disease) were >94% (kappa = 0.644-0.794). Response comparisons for Stage 2 questions on health risk factors were also generally high (>82% agreement) but there were larger differences between reported and measured risk factors in Stage 3. CONCLUSIONS: Levels of agreement between the Stage 1 responses were substantial and support the use of this online option for pre-exercise screening. There were larger differences between self-reported and objectively measured health risk factors in Stages 2 and 3.


Subject(s)
Exercise , Internet , Surveys and Questionnaires , Adolescent , Adult , Aged , Female , Humans , Male , Middle Aged
20.
Article in English | MEDLINE | ID: mdl-29580876

ABSTRACT

INTRODUCTION: Assessment of effects of potential drug candidates on the respiratory system is part of the regulatory preclinical safety assessment conducted prior to first in human trials (FTIH). Commonly, this is carried out utilizing head out plethysmography (HOP) or whole body plethysmography (WBP) which record only ventilatory parameters. When dosing via the inhaled route a more thorough respiratory assessment, including a direct measure of airway mechanics, is desirable. The aim of the present work was to improve the strategy for respiratory safety testing by a) evaluating a telemetered pleural pressure - HOP (PP-HOP) model and b) evaluating a crossover study design protocol in the WBP model to reduce variability and animal usage. METHODS: For the PP- HOP model, rats were surgically implanted with a telemetry device for measurement of pleural pressure. Animals were placed in HOP tubes and respiratory function assessed when exposed to methacholine at doses of 0 (saline only), 0.42, 1.6 and 3.8 mg/kg. WBP assessment was performed in rats in a crossover study design when treated with theophylline at doses of 0 (saline only), 3, 10 and 30 mg/kg. RESULTS: Data from the PP-HOP study confirmed the expected changes in ventilatory parameters and airway mechanics in response to inhaled methacholine, including an increase in pulmonary resistance and decrease in tidal volume. Data from the WBP crossover study demonstrated similar sensitivity and statistical power to detect changes in respiratory rate and tidal volume to a standard parallel group design. CONCLUSION: Measurement of PP-HOP in a stand-alone safety pharmacology study in conjunction with HOP assessment conducted as part of a toxicology study, represents an improved respiratory testing strategy for inhaled drugs. For compounds administered by other routes, we conclude that use of WBP using a crossover dosing design is a suitable alternative to parallel dosing groups, with a significant reduction in animal numbers and no loss of statistical power.


Subject(s)
Animal Experimentation/legislation & jurisprudence , Bronchodilator Agents/administration & dosage , Models, Animal , Respiratory Mechanics/drug effects , Theophylline/administration & dosage , Administration, Inhalation , Animals , Bronchodilator Agents/toxicity , Cross-Over Studies , Male , Plethysmography, Whole Body/methods , Rats , Rats, Wistar , Respiratory Mechanics/physiology , Telemetry/methods , Theophylline/toxicity , Tidal Volume/drug effects , Tidal Volume/physiology
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