Mothers supporting play as a choice for children with disabilities within a culturally and linguistically diverse community.

Background: Play is a right for children; an essential childhood occupation influenced by their family environment. Despite increasing recognition of unstructured outdoor play benefits, children with disabilities experience limited play opportunities.Aim: To apply a capabilities approach lens to understand outdoor play decision-making by mothers of children with disabilities within a culturally and linguistically diverse community.Materials and methods: Data collection for this case study involved semi-structured interviews with five mothers of primary school-aged children with disabilities and a week-long survey that profiled their children's outdoor play. Analysis was thematic and involved identifying barriers and opportunities at each ecocultural layer, aggregating strategies families used to address the barriers, and understanding their overall play decision-making.Findings: Mothers considered the child's interests and abilities, valued play as both a means and ends, planned for play, and facilitated in the moment as required. Multiple factors influenced mothers' outdoor play decisions. Mothers' values were child-centred, positively influencing the child's play opportunities.Conclusion and significance: This study's capabilities lens could inform professions such as occupational therapy to support families of children with disabilities from culturally diverse communities to advocate for play opportunities across settings.

Trunk Exercises Improve Balance in Parkinson Disease: A Phase II Randomized Controlled Trial.

BACKGROUND AND PURPOSE: Trunk control is important for maintaining balance; hence, deficient trunk control may contribute to balance problems in people with Parkinson disease (PD). Unfortunately, this deficit is poorly managed with pharmacological therapies, emphasizing the need for alternative therapies for these patients. This randomized controlled trial sought to examine the effects of a 12-week trunk-specific exercise-based intervention on balance in people with PD. METHODS: Twenty-four people with PD and with a history of falls completed assessments of motor symptom severity, balance confidence, mobility, quality of life, and quiet-standing balance. Participants were then randomized to receive either 12 weeks of exercise or education and reassessed after 12 and 24 weeks. RESULTS: Linear mixed-models analyses showed no significant changes in clinical outcomes following the intervention. However, during quiet standing, sway area on a foam surface without vision was reduced for the exercise group at 12 (-6.9 ± 3.1 cm; 95% confidence interval [CI] = -13.1 to -0.7; P = 0.029; d = 0.66) and 24 weeks (-7.9 ± 3.1 cm; 95% CI = -14.1 to -1.7; P = 0.013; d = 0.76). Furthermore, the exercise group demonstrated reduced sway variability at 12 (-0.2 ± 0.1 cm; 95% CI = -0.4 to 0.0; P = 0.042; d = 0.62) and 24 weeks in the medial-lateral direction (-0.2 ± 0.1 cm; 95% CI = -0.4 to 0.0; P = 0.043; d = 0.62). No changes in quiet standing balance were recorded for the education group. DISCUSSION AND CONCLUSIONS: The results of this study suggest that exercise-based interventions targeting trunk strength, endurance, and mobility may be effective for improving quiet-standing balance in people with PD. However, additional research is needed to determine whether these improvements are sufficient to reduce falls risk.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A254).

Alternate Subthalamic Nucleus Deep Brain Stimulation Parameters to Manage Motor Symptoms of Parkinson's Disease: Systematic Review and Meta-analysis.

BACKGROUND: The use of alternate frequencies, amplitudes, and pulse widths to manage motor symptoms in Parkinson's disease (PD) patients with subthalamic nucleus deep brain stimulation (STN-DBS) is of clinical interest, but currently lacks systematic evidence. OBJECTIVE/HYPOTHESIS: Systematically review whether alternate STN-DBS settings influence the therapy's efficacy for managing PD motor symptoms. METHODS: Systematic searches identified studies that; involved bilateral STN-DBS PD patients; manipulated ≥ 1 STN-DBS parameter (e.g., amplitude); assessed ≥ 1 motor symptom (e.g., tremor); and contrasted the experimental and chronic stimulation settings. A Mantel-Haenszel random-effects meta-analysis compared the UPDRS-III sub-scores at low (60-Hz) and high frequencies ( ≥ 130 Hz). Inter-study heterogeneity was assessed with the Cohen's χ2 and I2 index, while the standard GRADE evidence assessment examined strength of evidence. RESULTS: Of the 21 included studies, 17 investigated the effect of alternate stimulation frequencies, five examined alternate stimulation amplitudes, and two studied changes in pulse width. Given the available data, meta-analyses were only possible for alternate stimulation frequencies. Analysis of the heterogeneity amongst the included studies indicated significant variability between studies and, on the basis of the GRADE framework, the pooled evidence from the meta-analysis studies was of very low quality due to the significant risks of bias. CONCLUSIONS: The meta-analysis reported a very low quality of evidence for the efficacy of low-frequency STN-DBS for managing PD motor symptoms. Furthermore, it highlighted that lower amplitudes lead to the re-emergence of motor symptoms and further research is needed to understand the potential benefits of alternate STN-DBS parameters for PD patients.

Planning for outdoor play: Government and family decision-making.

BACKGROUND: Despite indisputable developmental benefits of outdoor play, children with disabilities can experience play inequity. Play decisions are multifactorial; influenced by children's skills and their familial and community environments. Government agencies have responsibilities for equity and inclusion of people with disabilities; including in play. AIM: This multiple-perspective case study aimed to understand outdoor play decision-making for children with disabilities from the perspectives and interactions of: local government and families of primary school-aged children with disabilities. MATERIAL AND METHOD: Five mothers, four local government employees, and two not-for-profit organization representatives participated in semi-structured interviews. Inductive and iterative analyzes involved first understanding perspectives of individuals, then stakeholders (local government and families), and finally similarities and differences through cross-case analysis. FINDINGS: Local government focused more on physical access, than social inclusion. Local government met only minimal requirements and had little engagement with families. This resulted in poor understanding and action around family needs and preferences when designing public outdoor play spaces. CONCLUSION AND SIGNIFICANCE: To increase meaningful choice and participation in outdoor play, government understanding of family values and agency around engagement with local government needs to improve. Supporting familial collective capabilities requires understanding interactions between individuals, play, disability, and outdoor play environments.

Sex Differences in Physical Fitness Characteristics and Match-Play Demands in Adolescent Netball: Should Male and Female Adolescents Co-compete in Netball?

Tissera, KM, Naughton, GA, Gabbett, TJ, Krause, LM, Moresi, MP, and Benson, AC. Sex differences in physical fitness characteristics and match-play demands in adolescent netball: Should male and female adolescents co-compete in netball? J Strength Cond Res 33(3): 846-856, 2019-Sports participation offers multifaceted benefits, especially during adolescence. However, policies relating to male and female adolescents co-competing in team sports can be prohibitive and lack an evidence base. This study aimed to strengthen evidence on coparticipation of male and female adolescents playing recreational netball. Off-court fitness characteristics (power, speed, agility, and high-speed intermittent running) and match-play performances from global positioning system (GPS) and video analysis were compared in adolescent males (n = 34, mean ± SD, age, 15.2 ± 0.8 years) and females (n = 45, mean ± SD, age, 14.9 ± 0.7 years), with previous recreational netball experience. Independent t-tests showed adolescent men outperforming females in all off-court fitness characteristics (p < 0.001). Two-way analyses of variance explored sex-based interactions in match-play (GPS accelerometer data and notational analyses) and type of competition (mixed-/single-sex formats) in forty-two 7-minute matches. Overall, no differences in match-play performances were found between males and females (p > 0.05). Notational skill-based comparisons showed that male skills were better in mixed- than single-sex matches. Conversely, competition format did not alter skills of females. Despite more netball experience in females and superior off-court fitness characteristics in males, on-court performance differences between males and females were minimal in these recreational adolescent netball players. Coparticipation in netball was not detrimental to the performance of either sex.

Equity of Physical Characteristics Between Adolescent Males and Females Participating in Single- or Mixed-Sex Sport.

Krause, LM, Naughton, GA, Benson, AC, and Tibbert, S. Equity of physical characteristics between adolescent males and females participating in single- or mixed-sex sport. J Strength Cond Res 32(5): 1415-1421, 2018-Policies on single- or mixed-sex junior sports participation continue to be challenged publically and legally. Often challenges relate to perceptions of size and performance variability between adolescent males and females, yet the evidence base behind these challenges lacks recent review and rigor. Physical performance was compared between males and females from 2 groups of younger (<13 years, n = 109, 67% females, 33% males) and older (≥13 years, n = 108, 43% females, 57% males) adolescents. Using a cross-sectional design, adolescents were tested for speed, strength, power, and endurance. No sex differences were found for most of the physical test results in the <13 years age group, although males showed greater endurance (p = 0.020) and upper-body strength (p = 0.010) than females. However, among adolescents aged ≥13 years, males scored better than females in all physical tests, without exception (p > 0.05). Further explorations comparing how many females in the same age grouping shared test results equal to or greater than the top third of males were fewer in the older than younger age group. Equality of participation in mixed-sex sport becomes more difficult to guarantee for older adolescents when results from generic sport-related physical test performances are considered.

Bone Health of Young Male Gymnasts: A Systematic Review.

PURPOSE: To synthesize existing literatures on the impact of gymnastics participation on the skeletal health of young male gymnasts. METHODS: Following a systematic search, 12 studies were included in this review. Quality of included studies was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE modified) criteria. RESULTS: Assessment of skeletal health varied between and within imaging modality protocols. Gymnasts had higher total bone content, greater total and trabecular bone density, larger bone size, a thicker cortex, and higher estimates of bone strength than controls. Recreational studies reported no difference in height or weight between gymnasts and controls; however, elite gymnasts were shorter and lighter than nongymnasts. STROBE scores ranged from 65% to 95%. CONCLUSION: Gymnastics participation may be beneficial to the bone health of young males as gymnasts had higher bone density and bone mineral content, larger bones, and greater estimates of bone strength than controls.

Neuromuscular Impairments Are Associated With Impaired Head and Trunk Stability During Gait in Parkinson Fallers.

Background The trunk plays a critical role in attenuating movement-related forces that threaten to challenge the body's postural control system. For people with Parkinson's disease (PD), disease progression often leads to dopamine-resistant axial symptoms, which impair trunk control and increase falls risk. Objective This prospective study aimed to evaluate the relationship between impaired trunk muscle function, segmental coordination, and future falls in people with PD. Methods Seventy-nine PD patients and 82 age-matched controls completed clinical assessments and questionnaires to establish their medical history, symptom severity, balance confidence, and falls history. Gait characteristics and trunk muscle activity were assessed using 3-dimensional motion analysis and surface electromyography. The incidence, cause, and consequence of any falls experienced over the next 12 months were recorded and indicated that 48 PD and 29 control participants fell at least once during this time. Results PD fallers had greater peak and baseline lumbar multifidus (LMF) and thoracic erector spinae (TES) activations than control fallers and nonfallers. Analysis of covariance indicated that the higher LMF activity was attributable to the stooped posture adopted by PD fallers, but TES activity was independent of medication use, symptom severity, and trunk orientation. Furthermore, greater LMF and TES baseline activity contributed to increasing lateral head, trunk, and pelvis movements in PD fallers but not nonfallers or controls. Conclusions The results provide evidence of neuromuscular deficits for PD fallers that are independent of medications, symptom severity, and posture and contribute to impaired head, trunk, and pelvis control associated with falls in this population.

Validity and Reliability of a Submaximal Intermittent Running Test in Elite Australian Football Players.

Veugelers, KR, Naughton, GA, Duncan, CS, Burgess, DJ, and Graham, SR. Validity and reliability of a submaximal intermittent running test in elite Australian football players. J Strength Cond Res 30(12): 3347-3353, 2016-The aim of this article was to determine the validity and reliability of a submaximal intermittent running (SIR) test in elite Australian rules football (ARF) players. Heart rate (HR) responses of 38 elite ARF players to both the SIR and the yo-yo intermittent recovery 2 (YYIR2) tests were compared over 2 trials. Linear regression analysis was used to examine the relationship between SIR test HR responses and YYIR2 test performance. Heart rate responses of 25 elite ARF players to the SIR test were monitored over 3 trials. Day-to-day reliability was determined using intraclass correlation coefficient (ICC), typical error of measurement, coefficient of variation (CV), and smallest worthwhile change. Large inverse correlations were reported between 2-, 3-, and 4-minute HR during the SIR test and YYIR2 test distance (r = -0.58 to -0.61, p < 0.01). Heart rate recovery after 2 and 3 minutes of the SIR test was moderately correlated to YYIR2 distance (r = 0.32-0.35, p ≤ 0.05). Strong correlations for ICC (r = 0.90-0.97) and low CV (1.3-9.2%) were reported for all HR variables. Monitoring HR during the SIR test is a valid and reliable indicator of YYIR2 test performance in elite ARF players. These findings support the use of the SIR test as a regular and non-fatiguing indicator of intermittent running capacity.

Assessing stability in mild and moderate Parkinson's disease: Can clinical measures provide insight?

This cross-sectional study aimed to investigate the relationship between accelerometer-derived measures of movement rhythmicity and clinical measures of mobility, balance confidence and gait difficulty in people with Parkinson's disease (PD). Twenty-nine independently-living PD patients (Hoehn & Yahr Stages 1-3) with no history of significant injury or orthopaedic/deep brain stimulation surgery were recruited from a database of patients who had expressed an interest to participate in research. Participants completed clinical assessments of mobility, postural stability, balance confidence and symptom severity, while head and trunk rhythmicity was evaluated during gait using accelerometers. Following data collection, patients were stratified based on disease stage into either a Mild (Hoehn & Yahr Stage 1) or Moderate (Hoehn & Yahr Stages 2-3) PD group. The results highlighted that the Moderate PD group had poorer quality of life, reduced balance confidence and increased gait and falls difficulty. Furthermore, for these patients, gait disability and the number of previous falls were both negatively correlated with multiple components of head and trunk rhythmicity. For the Mild PD group, six-meter walk time was positively correlated with ML head rhythmicity and linear regression highlighted a significant predictive relationship between these outcomes. For the Mild and Moderate PD groups, balance confidence respectively predicted anterior-posterior trunk rhythmicity and vertical head rhythmicity. While these findings demonstrate that falls history and the Gait and Falls questionnaire provide moderate insight into head and trunk rhythmicity in Moderate PD patients, objective and clinically-feasible measures of postural instability would assist with the management of these symptoms.

Use of a Short-Form Balance Confidence Scale to Predict Future Recurrent Falls in People With Parkinson Disease.

OBJECTIVES: To assess whether the 16-item Activities-specific Balance Confidence scale (ABC-16) and short-form 6-item Activities-specific Balance Confidence scale (ABC-6) could predict future recurrent falls in people with Parkinson disease (PD) and to validate the robustness of their predictive capacities. DESIGN: Twelve-month prospective cohort study. SETTING: General community. PARTICIPANTS: People with idiopathic PD (N=79). INTERVENTIONS: Clinical tests were conducted to assess symptom severity, balance confidence, and medical history. Over the subsequent 12 months, participants recorded any falls on daily fall calendars, which they returned monthly by reply paid post. MAIN OUTCOME MEASURES: Logistic regression and receiver operating characteristic analyses estimated the sensitivities and specificities of the ABC-16 and ABC-6 for predicting future recurrent falls in this cohort, and "leave-one-out" validation was used to assess their robustness. RESULTS: Of the 79 patients who completed follow-up, 28 (35.4%) fell more than once during the 12-month period. Both the ABC-16 and ABC-6 were significant predictors of future recurrent falls, and moderate sensitivities (ABC-16: 75.0%; ABC-6: 71.4%) and specificities (ABC-16: 76.5%; ABC-6: 74.5%) were reported for each tool for a cutoff score of 77.5 and 65.8, respectively. CONCLUSIONS: The results have significant implications and demonstrate that the ABC-16 and ABC-6 independently identify patients with PD at risk of future recurrent falls.

The effect of intense exercise periods on physical and technical performance during elite Australian Football match-play: A comparison of experienced and less experienced players.

OBJECTIVES: The physical and technical responses of experienced (≥5 years) and less experienced (1-4 years) elite Australian Football (AF) players were compared following the most intense passages of match-play. DESIGN: Descriptive cohort study. METHODS: Time-motion analyses were performed using global positioning systems (MinimaxX S4, Catapult Innovations, Melbourne, Australia) on one elite AF team during 13 matches. The global positioning data were categorised into total distance, low-speed activity (0-2.78ms(-1)), moderate-speed running (2.79-4.14ms(-1)) and high-speed running (≥4.15ms(-1)) distances. A standardised 5-point technical coding criteria was used to rate the number and quality of skill involvements during match-play. RESULTS: Following the most intense 3-min running period the experienced players covered greater distances at high-speeds in match quarters two (effect size, ES=0.42±0.30) and three (ES=0.38±0.33) than their less experienced counterparts. Compared with less experienced players, experienced players performed more skill involvements during the second quarter (ES=0.42±0.33) and fourth quarter peak 3-min bouts of exercise intensity (ES=0.40±0.30) and quarter one (ES=0.49±0.29) and three subsequent periods (ES=0.33±0.20). CONCLUSIONS: Less experienced players exhibited greater reductions in physical and technical performance following peak periods of match-play. These findings suggest that training may require a greater emphasis on developing the ability of less experienced players to maintain physical performance and gain possession of the football following intense periods of match-play.

Effects of a Multi-Disciplinary Lifestyle Intervention on Cardiometabolic Risk Factors in Young Women with Abdominal Obesity: A Randomised Controlled Trial.

BACKGROUND: Young women are under-represented in cardiovascular disease research, with obesity and cardiometabolic risk factor interventions generally targeting older adults. Furthermore, appropriate study designs for young women remain uncertain. This study aimed to assess the impact of a 12 week multi-disciplinary lifestyle intervention on cardiometabolic risk factors in premenopausal women with abdominal obesity. METHODS: Women aged 18-30 y with abdominal obesity [waist circumference (WC) ≥ 80 cm] were randomised to a 12 week lifestyle intervention (n = 26) of physical activity, nutrition education and cognitive behavioural therapy, or a wait-list control group (n = 17). Both groups completed anthropometric, biochemical, nutrition and fitness testing, at pre (0 weeks) and post (12 weeks), with intervention participants completed follow-up testing at 24 weeks. RESULTS: Results from a linear mixed model showed no between-group differences, other than increased physical activity in the intervention group, at post. In the intervention group alone, positive within-group changes were observed in WC, waist-hip-ratio (WHR), waist-height-ratio (WHtR), resting heart rate, blood pressure, predicted VO2max, and total energy intake. Most changes were maintained at 24 weeks post-intervention. Similar within-group improvements were observed in control participants in WC, WHR, WHtR, and systolic blood pressure but no changes were detected in physical activity and nutrition. CONCLUSIONS: Cardiometabolic risk factors were decreased as a result of a lifestyle intervention in young women with abdominal obesity. It is difficult to describe observations in the control group without greater understanding of the behaviour of wait-list participants. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12612001017819.

Young Women With Abdominal Obesity Have Subclinical Myocardial Dysfunction.

BACKGROUND: Abdominal obesity is an independent risk factor for cardiovascular disease. The effect of abdominal obesity on myocardial function in young obese women remains unknown. Therefore, we aimed to investigate cardiac morphology and function, myocardial deformation, and mechanical indices, in young women with and without abdominal obesity. METHODS: Cross-sectional analyses of 39 women with abdominal obesity (waist circumference ≥ 80 cm) and 33 nonobese control subjects (waist circumference < 80 cm) aged 18-30 years underwent conventional echocardiographic measures of cardiac morphology and function together with tissue Doppler, and 2-dimensional speckle tracking measures of myocardial deformation and mechanics. Cardiometabolic risk factors including anthropometric, hypertension, biochemistry, and fitness were also assessed. RESULTS: Standard echocardiography results for cardiac morphology and function were similar between groups, with the exception of larger left atrial dimensions in women with abdominal obesity (P ≤ 0.05). Compared with control subjects, women with abdominal obesity also demonstrated reduced systolic and diastolic mitral annular plane velocities, increased left atrial pressure surrogates (E/diastolic mitral annular plane velocity), and prolonged timing measures of diastolic function including isovolumic relaxation time and transmitral deceleration time (P ≤ 0.05). In addition, longitudinal strain and diastolic strain rate were reduced in women with abdominal obesity (P ≤ 0.05) but circumferential deformation and myocardial mechanics (twist indices and rotation) were preserved. Markers of abdominal obesity retained an independent direct correlation with parameters of cardiac dysfunction, explaining 12%-39% of the overall variability. CONCLUSIONS: A young, otherwise healthy group of women with abdominal obesity displayed subclinical cardiac dysfunction indicated using selected tissue Doppler imaging and speckle tracking echocardiography measures.

Wearable sensor use for assessing standing balance and walking stability in people with Parkinson's disease: a systematic review.

BACKGROUND: Postural instability and gait disability threaten the independence and well-being of people with Parkinson's disease and increase the risk of falls and fall-related injuries. Prospective research has shown that commonly-used clinical assessments of balance and walking lack the sensitivity to accurately and consistently identify those people with Parkinson's disease who are at a higher risk of falling. Wearable sensors provide a portable and affordable alternative for researchers and clinicians who are seeking to objectively assess movements and falls risk in the clinical setting. However, no consensus currently exists on the optimal placements for sensors and the best outcome measures to use for assessing standing balance and walking stability in Parkinson's disease patients. Hence, this systematic review aimed to examine the available literature to establish the best sensor types, locations and outcomes to assess standing balance and walking stability in this population. METHODS: Papers listed in three electronic databases were searched by title and abstract to identify articles measuring standing balance or walking stability with any kind of wearable sensor among adults diagnosed with PD. To be eligible for inclusion, papers were required to be full-text articles published in English between January 1994 and December 2014 that assessed measures of standing balance or walking stability with wearable sensors in people with PD. Articles were excluded if they; i) did not use any form of wearable sensor to measure variables associated with standing balance or walking stability; ii) did not include a control group or control condition; iii) were an abstract and/or included in the proceedings of a conference; or iv) were a review article or case study. The targeted search of the three electronic databases identified 340 articles that were potentially eligible for inclusion, but following title, abstract and full-text review only 26 articles were deemed to meet the inclusion criteria. Included articles were assessed for methodological quality and relevant data from the papers were extracted and synthesized. RESULTS: Quality assessment of these included articles indicated that 31% were of low methodological quality, while 58% were of moderate methodological quality and 11% were of high methodological quality. All studies adopted a cross-sectional design and used a variety of sensor types and outcome measures to assess standing balance or walking stability in people with Parkinson's disease. Despite the typically low to moderate methodological quality, 81% of the studies reported differences in sensor-based measures of standing balance or walking stability between different groups of Parkinson's disease patients and/or healthy controls. CONCLUSION: These data support the use of wearable sensors for detecting differences in standing balance and walking stability between people with PD and controls. Further high-quality research is needed to better understand the utility of wearable sensors for the early identification of Parkinson's disease symptoms and for assessing falls risk in this population. PROSPERO REGISTRATION: CRD42014010838.

Understanding mismatches in body size, speed and power among adolescent rugby union players.

OBJECTIVES: With adolescent sport increasingly challenged by mismatches in size, new strategies are important to maximize participation. The objectives were to (1) improve the understanding of mismatches in physical size, speed and power in adolescent rugby union players, (2) explore associations between size and performance with demographic, playing-history, and injury profiles, and (3) explore the applicability of existing criteria for age/body mass-based dispensation (playing-down) strategies. DESIGN: Cross-sectional study. METHODS: Four hundred and eighty-five male community rugby union players were recruited from three Australian states selected to represent community-based U12, U13, U14 and U15 players. Body mass, stature, speed (10, 30, and 40 m sprints) and lower-leg power (relative peak power and relative peak force) were measured. Independent student t-tests, linear regressions and Chi square analyses were undertaken. RESULTS: Mean values in age groups for size, speed and power masked considerable overlap in the ranges within specific age groups of adolescent rugby players. Only a small proportion of players (approximately 5%) shared the highest and lowest tertiles for speed, relative peak power and body mass. Physical size was not related to injury. The mean body mass of current community rugby union players was above the 75th percentile on normative growth-charts. CONCLUSION: The notion that bigger, faster, and more powerful characteristics occur simultaneously in adolescent rugby players was not supported in the present study. Current practices in body mass-based criteria for playing down an age group lack a sufficient evidence for decision-making. Dispensation solely based on body mass may not address mismatch in junior rugby union.

The impact of data reduction on the intra-trial reliability of a typical measure of lower limb musculoskeletal stiffness.

Double-leg repeated jumping tasks are commonly used as measures of lower limb stiffness in exercise science research. Within similar stiffness calculations, variation in data-reduction criteria exists. The impact of these varied data-reduction methods on stiffness measures is unknown. Sixteen adolescent female participants from varied physical activity backgrounds performed 15 self-paced, bent-knee continuous jumps (CJb) on two force plates. Leg stiffness was calculated as the ratio of the peak force and the centre of mass displacement for each contact. Using combinations of criteria based on previous literature, 83 data-reduction methods were applied to the raw data. Data reduction suitability was assessed based on intra-trial reliability, the number of participants excluded and the average contacts excluded. Four data-reduction methods were deemed suitable for use with adolescent female populations, with three consecutive contacts within 1 SD of the average jump frequency considered optimal. The average individual stiffness values were not greatly influenced by the data-reduction method; however, for a single participant, a stiffness change of up to 6 kN · m(-1) (30%) was observed. The role and potential impact of data-reduction methods used to evaluate measures of lower limb stiffness during repeated jumping tasks warrants consideration.

The relationship between workloads, physical performance, injury and illness in adolescent male football players.

BACKGROUND: The expectation that training enhances performance is well explored in professional sport. However, the additional challenges of physical and cognitive maturation may require careful consideration when determining workloads to enhance performance in adolescents. OBJECTIVE: The objective of this study was to determine the state of knowledge on the relationship between workloads, physical performance, injury and/or illness in adolescent male football players. METHODS: A systematic review of workloads, physical performance, injury and illness in male adolescent football players was conducted. Studies for this review were identified through a systematic search of six electronic databases (Academic Search Complete, CINAHL, PsycINFO, PubMed, SPORTDiscus, and Web of Science). For the purpose of this review, load was defined as the cumulative amount of stress placed on an individual from multiple training sessions and games over a period of time, expressed in terms of either the external workloads performed (e.g., resistance lifted, kilometres run) or the internal response (e.g., heart rate, rating of perceived exertion) to that workload. RESULTS: A total of 2,081 studies were initially retrieved from the six databases, of which 892 were duplicates. After screening the titles, abstracts and full texts, we identified 23 articles meeting our criteria around adolescent football players, workloads, physical performance, injury and/or illness. Seventeen articles addressed the relationship between load and physical performance, four articles addressed the relationship between load and injury and two articles addressed both. A wide range of training modalities were employed to improve the physical performance of adolescent football players, with strength training, high-intensity interval training, dribbling and small-sided games training, and a combination of these modalities in addition to normal football training, resulting in improved performances on a wide range of physiological and skill assessments. Furthermore, there was some (limited) evidence that higher workloads may be associated with the development of better physical qualities, with one study demonstrating enhanced submaximal interval shuttle run performance with each additional hour of training or game play. Of the few studies examining negative consequences associated with workloads, increases in training load led to increases in injury rates, while longer training duration was associated with a greater incidence of illness. CONCLUSION: The combined capacity for adolescent males to grow, train and improve physical performance highlights and underscores an exciting responsiveness to training in the football environment. However, the capacity to train has some established barriers for adolescents experiencing high workloads, which could also result in negative consequences. Additional research on stage-appropriate training for adolescent male footballers is required in order to address the knowledge gaps and enhance safe and efficient training practices.

Cardiometabolic and behavioural risk factors in young overweight women identified with simple anthropometric measures.

OBJECTIVES: This study aimed to (1) investigate cardiometabolic risk markers in young women (18-30 years) with overweight/obesity, and (2) establish whether the measures of waist circumference and body mass index possess similar associations of cardiometabolic risk. DESIGN: Cross-sectional. METHODS: Cardiometabolic risk factors including, anthropometric, metabolic syndrome markers, biochemical, and other health/fitness indicators were assessed in women when classified as overweight/obese by waist circumference [waist circumference 91.9 ± 10.1 cm, age 22.3 ± 3.5 years, n = 38] versus control [n = 30, waist circumference 71.4 ± 3.5 cm, age 20.1 ± 0.9 years], and when classified by body mass index [n=35, body mass index 32.2 ± 5.2 kg m(2), age 22.5 ± 3.6 years] versus control [body mass index 21.7 ± 1.9 kg m(2), age 20.1 ± 0.9 years, n=33]. RESULTS: Compared with controls, women with overweight/obesity (classified by waist circumference or body mass index) displayed elevated body mass, systolic blood pressure and homeostasis model assessment of insulin resistance, and reduced estimated [Formula: see text] and weekly physical activity, with no differences in self-reported energy intake. The unadjusted odds ratio of being classified with overweight/obesity and an elevated homeostasis model assessment of insulin resistance and/or less than recommended physical activity ranged between 5.1 and 10.0. Receiver operator characteristic curves indicated waist circumference, body mass index and waist-to-height ratio cut-off points of ≥ 84.2 cm, ≥ 30.6 kg m(-2) and ≥ 0.5, respectively, for homeostasis model assessment of insulin resistance, and ≥ 80.6 cm, ≥ 25.2 kg m(-2) and ≥ 0.46, respectively, for less than recommended physical activity. CONCLUSIONS: Waist circumference and body mass index have similar associations with cardiometabolic risk, with greater homeostasis model assessment of insulin resistance and lower physical activity, rather than differences in traditional metabolic syndrome markers, observed in young women with overweight/obesity.

Trunk muscle exercises as a means of improving postural stability in people with Parkinson's disease: a protocol for a randomised controlled trial.

INTRODUCTION: Exercise has been shown to improve clinical measures of strength, balance and mobility, and in some cases, has improved symptoms of tremor and rigidity in people with Parkinson's disease (PD). However, to date, no research has examined whether improvements in trunk control can remedy deficits in dynamic postural stability in this population. The proposed randomised controlled trial aims to establish whether a 12-week exercise programme aimed at improving dynamic postural stability in people with PD; (1) is more effective than education; (2) is more effective when training frequency is increased; and (3) provides greater long-term benefits than education. METHODS/DESIGN: Forty-five community-dwelling individuals diagnosed with idiopathic PD with a falls history will be recruited. Participants will complete baseline assessments including tests of cognition, vision, disease severity, fear of falling, mobility and quality of life. Additionally, participants will complete a series of standing balance tasks to evaluate static postural stability, while dynamic postural control will be measured during walking using head and trunk-mounted three-dimensional accelerometers. Following baseline testing, participants will be randomly-assigned to one of three intervention groups, who will receive either exercise once per week, exercise 3 days/week, or education. Participants will repeat the same battery of tests conducted at baseline after the 12-week intervention and again following a further 12-week sustainability period. DISCUSSION: This study has the potential to show that low-intensity and progressive trunk exercises can provide a non-invasive and effective means for maintaining or improving postural stability for people with PD. Importantly, if the programme is noted to be effective, it could be easily performed by patients within their home environment or under the guidance of available allied health professionals. TRIAL REGISTRATION NUMBER: The protocol for this study is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12613001175763).