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Background
Although associations between cardiovascular diseases and cognitive impairment are well known, the impact of cognitive performance on the success of patient education as a core component of cardiac rehabilitation remains insufficiently investigated so far.
Design
Prospective observational study in two inpatient cardiac rehabilitation centres between September 2014 and August 2015 with a follow-up six months after cardiac rehabilitation.
Method
At admission to and discharge from cardiac rehabilitation, the cognitive performance of 401 patients (54.5 ± 6.3 years, 80% men) following an acute coronary syndrome and/or coronary artery bypass graft was tested using the Montreal Cognitive Assessment. Patients’ disease-related knowledge was determined using a quiz (22 items for medical knowledge and 12 items for healthy lifestyle and behaviour) at both times and at follow-up. The change in knowledge after cardiac rehabilitation was analysed in multivariable regression models. Potentially influencing parameters (e.g. level of education, medication, cardiovascular risk factors, coronary artery bypass graft, comorbidities, exercise capacity) were considered.
Results
During cardiac rehabilitation, disease-related knowledge was significantly enhanced in both scales. At follow-up, the average level of medical knowledge was significantly reduced, while lifestyle knowledge remained at a stable level. The maintenance of knowledge after cardiac rehabilitation was predominantly predicted by prior knowledge, cognitive performance at discharge from cardiac rehabilitation and, in the case of medical knowledge, by coronary artery bypass graft.
Conclusion
Patient education in cardiac rehabilitation led to enhanced disease-related knowledge, but the maintenance of this essentially depended on patients’ cognitive performance, especially after coronary artery bypass graft. Therefore, patient education concepts in cardiac rehabilitation should be reconsidered and adjusted as needed.
Background: The LumiraDx INR Test is a new point-of-care diagnostic test designed to analyze fingerstick blood samples. The test was assessed in patients receiving phenprocoumon (NCT04074980).
Methods: Venous plasma international normalized ratio (INR) was measured using the LumiraDx INR Test. LumiraDx INR Test-ascertained capillary whole blood INR was compared with venous plasma INR measured using the IL ACL Elite Pro and Sysmex CS-5100 reference instruments.
Results: A total of 102 patients receiving phenprocoumon were recruited. The INR results from venous plasma and capillary whole blood that were analyzed on the LumiraDx INR Test correlated well with those measured using the IL ACL Elite Pro (plasma: n = 25, r = 0.981; capillary blood: n = 74, r = 0.949) and the Sysmex CS-5100 (n = 73, r = 0.950).
Conclusions: The LumiraDx INR Test showed high accuracy in analyzing venous plasma and capillary whole blood from patients receiving phenprocoumon.
Repetitive overhead motions in combination with heavy loading were identified as risk factors for the development of shoulder pain. However, the underlying mechanism is not fully understood. Altered scapular kinematics as a result of muscle fatigue is suspected to be a contributor. PURPOSE: To determine scapular kinematics and scapular muscle activity at the beginning and end of constant shoulder flexion and extension loading in asymptomatic individuals. METHODS: Eleven asymptomatic adults (28±4yrs; 1.74±0.13m; 74±16kg) underwent maximum isokinetic loading of shoulder flexion (FLX) and extension (EXT) in the sagittal plane (ROM: 20- 180°; concentric mode; 180°/s) until individual peak torque was reduced by 50%. Simultaneously 3D scapular kinematics were assessed with a motion capture system and scapular muscle activity with a 3-lead sEMG of upper and lower trapezius (UT, LT) and serratus anterior (SA). Scapular position angles were calculated for every 20° increment between 20-120° humerothoracic positions. Muscle activity was quantified by amplitudes (RMS) of the total ROM. Descriptive analyses (mean±SD) of kinematics and muscle activity at begin (taskB) and end (taskE) of the loading task was followed by ANOVA and paired t-tests. RESULTS: At taskB activity ranged from 589±343mV to 605±250mV during FLX and from 105±41mV to 164±73mV during EXT across muscles. At taskE activity ranged from 594±304mV to 875±276mV during FLX and from 97±33mV to 147±57mV during EXT. Differences with increased muscle activity were seen for LT and UT during FLX (meandiff= 141±113mV for LT, p<0.01; 191±153mV for UT, p<0.01). Scapula position angles continuously increased in upward rotation, posterior tilt and external rotation during FLX and reversed during EXT both at taskB and taskE. At taskE scapula showed greater external rotation (meandiff= 3.6±3.7°, p<0.05) during FLX and decreased upward rotation (meandiff= 1.9±2.3°, p<0.05) and posterior tilt (meandiff= 1.0±2.1°, p<0.05) during EXT across humeral positions. CONCLUSIONS: Force reduction in consequence of fatiguing shoulder loading results in increased scapular muscle activity and minor alterations in scapula motion. Whether even small changes have a clinical impact by creating unfavorable subacromial conditions potentially initiating pain remains unclear.
Background: As the COVID-19 pandemic continues to spread across the globe, the search for an effective medication to treat the symptoms of COVID-19 continues as well. It would be desirable to identify a medication that is already in use for another condition and whose side effect profile and safety data are already known and approved.
Objective: The objective of this study was to evaluate the effect of different medications on typical COVID-19 symptoms by using data from an online surveillance survey.
Methods: Between early April and late-July 2020, a total of 3654 individuals in Lower Saxony, Germany, participated in an online symptom-tracking survey conducted through the app covid-nein-danke.de. The questionnaire comprised items on typical COVID-19 symptoms, age range, gender, employment in patient-facing healthcare, housing status, postal code, previous illnesses, permanent medication, vaccination status, results of reverse transcription polymerase chain reaction (RT-PCR) and antibody tests for COVID-19 diagnosis, and consequent COVID-19 treatment if applicable. Odds ratio estimates with corresponding 95% CIs were computed for each medication and symptom by using logistic regression models.
Results: Data analysis suggested a statistically significant inverse relationship between typical COVID-19 symptoms self-reported by the participants and self-reported statin therapy and, to a lesser extent, antihypertensive therapy. When COVID-19 diagnosis was based on restrictive symptom criteria (ie, presence of 4 out of 7 symptoms) or a positive RT-PCR test, a statistically significant association was found solely for statins (odds ratio 0.28, 95% CI 0.1-0.78).
Conclusions: Individuals taking statin medication are more likely to have asymptomatic COVID-19, in which case they may be at an increased risk of transmitting the disease unknowingly. We suggest that the results of this study be incorporated into symptoms-based surveillance and decision-making protocols in regard to COVID-19 management. Whether statin therapy has a beneficial effect in combating COVID-19 cannot be deduced based on our findings and should be investigated by further study.
The patients’ view
(2020)
Aim:The aim of this meta-synthesis is to find out what it means for patients with age-related macular degeneration to live with visual impairment, how they cope with the illness and how they experience their medical care, including vascular endothelial growth factor inhibitor therapy. Method:Inclusion criteria: qualitative studies exploring patients' experiences with age-related macular degeneration in their daily lives and with medical care, published in journals in English or German. The included studies were analysed following the rules and principles of grounded theory. Results:For the analysis, twenty-four articles matching the inclusion criteria were identified. Three main analytic themes emerged from the included studies: (i) a life shaped by losses; (ii) the burden of medical treatment; and (iii) coping with vision loss. For patients, visual impairment/vision loss means living with multiple losses in various domains of life. With the introduction of vascular endothelial growth factor inhibitor therapy, patients with neovascular age-related macular degeneration have a good chance of slowing down the disease progression; therapy does, however, also represent a major burden. Conclusion:New strategies need to be conceived to reduce the burden of medical treatment and to improve the dissemination of information about age-related macular degeneration.
Teachers' attitudes toward inclusion are frequently cited as being an important predictor of how successfully a given inclusive school system is implemented. At the same time, beliefs about the nature of teaching and learning are discussed as a possible predictor of attitudes toward inclusion. However, more recent research emphasizes the need of considering implicit processes, such as automatic evaluations, when describing attitudes and beliefs. Previous evidence on the association of attitudes toward inclusion and beliefs about teaching and learning is solely based on explicit reports. Therefore, this study aims to examine the relationship between attitudes toward inclusion, beliefs about teaching and learning, and the subsequent automatic evaluations of pre-service teachers (N = 197). The results revealed differences between pre-service teachers' explicit attitudes/beliefs and their subsequent automatic evaluations. Differences in the relationship between attitudes toward inclusion and beliefs about teaching and learning occur when teachers focus either on explicit measures or automatic evaluations. These differences might be due to different facets of the same attitude object being represented. Relying solely on either explicit measures or automatic evaluations at the exclusion of the other might lead to erroneous assumptions about the relation of attitudes toward inclusion and beliefs about teaching and learning.
Objective: This study investigated intraindividual differences of intratendinous blood flow (IBF) in response to running exercise in participants with Achilles tendinopathy.
Design: This is a cross-sectional study.
Setting: The study was conducted at the University Outpatient Clinic.
Participants: Sonographic detectable intratendinous blood flow was examined in symptomatic and contralateral asymptomatic Achilles tendons of 19 participants (42 ± 13 years, 178 ± 10 cm, 76 ± 12 kg, VISA-A 75 ± 16) with clinically diagnosed unilateral Achilles tendinopathy and sonographic evident tendinosis.
Intervention: IBF was assessed using Doppler ultrasound “Advanced Dynamic Flow” before (Upre) and 5, 30, 60, and 120 min (U5–U120) after a standardized submaximal constant load run.
Main Outcome Measure: IBF was quantified by counting the number (n) of vessels in each tendon.
Results: At Upre, IBF was higher in symptomatic compared with asymptomatic tendons [mean 6.3 (95% CI: 2.8–9.9) and 1.7 (0.4–2.9), p < 0.01]. Overall, 63% of symptomatic and 47% of asymptomatic Achilles tendons responded to exercise, whereas 16 and 11% showed persisting IBF and 21 and 42% remained avascular throughout the investigation. At U5, IBF increased in both symptomatic and asymptomatic tendons [difference to baseline: 2.4 (0.3–4.5) and 0.9 (0.5–1.4), p = 0.05]. At U30 to U120, IBF was still increased in symptomatic but not in asymptomatic tendons [mean difference to baseline: 1.9 (0.8–2.9) and 0.1 (-0.9 to 1.2), p < 0.01].
Conclusion: Irrespective of pathology, 47–63% of Achilles tendons responded to exercise with an immediate acute physiological IBF increase by an average of one to two vessels (“responders”). A higher amount of baseline IBF (approximately five vessels) and a prolonged exercise-induced IBF response found in symptomatic ATs indicate a pain-associated altered intratendinous “neovascularization.”
How do people decide which risks they want to get informed about? The present study examines the role of the availability and affect heuristics on these decisions. Participants (N= 100, aged 19-72 years) selected for which of 23 cancers they would like to receive an information brochure, reported the number of occurrences of each type of cancer in their social circle (availability), and rated their dread reaction to each type of cancer (affect); they also made relative judgments about which of 2 cancers was more common in Germany (judged risk). Participants tended to choose information brochures for those cancers for which they indicated a higher availability within their social networks as well as for cancers they dreaded. Mediation analyses suggested that the influence of availability and affect on information choice was only partly mediated by judged risk. The results demonstrate the operation of 2 key judgment heuristics (availability and affect), previously studied in risk perception, also in decisions about information choice. We discuss how our findings can be used to identify which risks are likely to fall from people's radar.
Background
Despite numerous studies and meta-analyses the prognostic effect of cardiac rehabilitation is still under debate. This update of the Cardiac Rehabilitation Outcome Study (CROS II) provides a contemporary and practice focused approach including only cardiac rehabilitation interventions based on published standards and core components to evaluate cardiac rehabilitation delivery and effectiveness in improving patient prognosis.
Design
A systematic review and meta-analysis.
Methods
Randomised controlled trials and retrospective and prospective controlled cohort studies evaluating patients after acute coronary syndrome, coronary artery bypass grafting or mixed populations with coronary artery disease published until September 2018 were included.
Resulte
Based on CROS inclusion criteria out of 7096 abstracts six additional studies including 8671 patients were identified (two randomised controlled trials, two retrospective controlled cohort studies, two prospective controlled cohort studies). In total, 31 studies including 228,337 patients were available for this meta-analysis (three randomised controlled trials, nine prospective controlled cohort studies, 19 retrospective controlled cohort studies; 50,653 patients after acute coronary syndrome 14,583, after coronary artery bypass grafting 163,101, mixed coronary artery disease populations; follow-up periods ranging from 9 months to 14 years). Heterogeneity in design, cardiac rehabilitation delivery, biometrical assessment and potential confounders was considerable. Controlled cohort studies showed a significantly reduced total mortality (primary endpoint) after cardiac rehabilitation participation in patients after acute coronary syndrome (prospective controlled cohort studies: hazard ratio (HR) 0.37, 95% confidence interval (CI) 0.20-0.69; retrospective controlled cohort studies HR 0.64, 95% CI 0.53-0.76; prospective controlled cohort studies odds ratio 0.20, 95% CI 0.08-0.48), but the single randomised controlled trial fulfilling the CROS inclusion criteria showed neutral results. Cardiac rehabilitation participation was also associated with reduced total mortality in patients after coronary artery bypass grafting (retrospective controlled cohort studies HR 0.62, 95% CI 0.54-0.70, one single randomised controlled trial without fatal events), and in mixed coronary artery disease populations (retrospective controlled cohort studies HR 0.52, 95% CI 0.36-0.77; two out of 10 controlled cohort studies with neutral results).
Conclusion
CROS II confirms the effectiveness of cardiac rehabilitation participation after acute coronary syndrome and after coronary artery bypass grafting in actual clinical practice by reducing total mortality under the conditions of current evidence-based coronary artery disease treatment. The data of CROS II, however, underscore the urgent need to define internationally accepted minimal standards for cardiac rehabilitation delivery as well as for scientific evaluation.
Eccentric exercises (ECC) induce reversible muscle damage, delayed-onset muscle soreness and an inflammatory reaction that is often followed by a systemic anti-inflammatory response. Thus, ECC might be beneficial for treatment of metabolic disorders which are frequently accompanied by a low-grade systemic inflammation. However, extent and time course of a systemic immune response after repeated ECC bouts are poorly characterized.
PURPOSE: To analyze the (anti-)inflammatory response after repeated ECC loading of the trunk.
METHODS: Ten healthy participants (33 ± 6 y; 173 ± 14 cm; 74 ± 16 kg) performed three isokinetic strength measurements of the trunk (concentric (CON), ECC1, ECC2, each 2 wks apart; flexion/extension, velocity 60°/s, 120s MVC). Pre- and 4, 24, 48, 72, 168h post-exercise, muscle soreness (numeric rating scale, NRS) was assessed and blood samples were taken and analyzed [Creatine kinase (CK), C-reactive protein (CRP), Interleukin-6 (IL-6), IL-10, Tumor necrosis factor-α (TNF-α)]. Statistics were done by Friedman‘s test with Dunn‘s post hoc test (α=.05).
RESULTS: Mean peak torque was higher during ECC1 (319 ± 142 Nm) than during CON (268 ± 108 Nm; p<.05) and not different between ECC1 and ECC2 (297 ± 126 Nm; p>.05). Markers of muscle damage (peaks post-ECC1: NRS 48h, 4.4±2.9; CK 72h, 14407 ± 19991 U/l) were higher after ECC1 than after CON and ECC2 (p<.05). The responses over 72h (stated as Area under the Curve, AUC) were abolished after ECC2 compared to ECC1 (p<.05) indicating the presence of the repeated bout effect. CRP levels were not changed. IL-6 levels increased 2-fold post-ECC1 (pre: 0.5 ± 0.4 vs. 72h: 1.0 ± 0.8 pg/ml). The IL-6 response was enhanced after ECC1 (AUC 61 ± 37 pg/ml*72h) compared to CON (AUC 33 ± 31 pg/ml*72h; p<.05). After ECC2, the IL-6 response (AUC 43 ± 25 pg/ml*72h) remained lower than post-ECC1, but the difference was not statistically significant. Serum levels of TNF-α and of the anti-inflammatory cytokine IL-10 were below detection limits. Overall, markers of muscle damage and immune response showed high inter-individual variability.
CONCLUSION: Despite maximal ECC loading of a large muscle group, no anti-inflammatory and just weak inflammatory responses were detected in healthy adults. Whether ECC elicits a different reaction in inflammatory clinical conditions is unclear.
Eccentric (ECC) exercises might cause muscle damage, characterized by delayed-onset muscle soreness, elevated creatine kinase (CK) levels and local muscle oedema, shown by elevated T2 times in magnet resonance imaging (MRI) scans. Previous research suggests a high inter-individual difference regarding these systemic and local responses to eccentric workload. PURPOSE: To analyze ECC exercise-induced muscle damage in lumbar paraspinal muscles assessed via MRI. METHODS: Ten participants (3f/7m; 33±6y; 174±8cm; 71±12kg) were included in the study. Quantitative paraspinal muscle constitution of M. erector spinae and M. multifidius were assessed in supine position before and 72h after an intense eccentric trunk exercise bout in a mobile 1.5 tesla MRI device. MRI scans were recorded on spinal level L3 (T2-weighted TSE echo sequences, 11 slices, 2mm slice thickness, 3mm gap, echo times: 20, 40, 60, 80, 100ms, TR time: 2500ms). Muscle T2 times were calculated for manually traced regions of interest of the respective muscles with an imaging software. The exercise protocol was performed in an isokinetic device and consisted of 120sec alternating ECC trunk flexion-extension with maximal effort. Venous blood samples were taken before and 72h after the ECC exercise. Descriptive statistics (mean±SD) and t-testing for pre-post ECC exercises were performed. RESULTS: T2 times increased from pre- to post-ECC MRI measurements from 55±3ms to 79±28ms in M. erector spinae and from 62±5ms to 78±24ms in M. multifidius (p<0.001). CK increased from 126±97 U/L to 1447±20579 U/L. High SDs of T2 time and CK in post-ECC measures could be due to inter-individual reactions to ECC exercises. 3 participants showed high local and systemic reactions (HR) with T2 time increases of 120±24% (M. erector spinae) and 73±50% (M. multifidius). In comparison, the remaining 7 participants showed increases of 11±12% (M. erector spinae) and 7±9% (M. multifidius) in T2 time. Mean CK increased 9.5-fold in the 3 HR subjects compared with the remaining 7 subjects. CONCLUSIONS: The 120sec maximal ECC trunk flexion-extension protocol induced high amounts of muscle damage in 3 participants. Moderate to low responses were found in the remaining 7 subjects, assuming that inter-individual predictors play a role regarding physiological responses to ECC workload.
Progression or impediment of fundamental motor skills performance (FMSP) in children depends on internal and environmental factors. Shoes as an environmental constraint are believed to affect these movements as children showed to perform qualitatively better with sports shoes than flip-flop sandals. However, locomotor performance assessments based on biomechanical variables are limited. Therefore, the objective of this experiment was to assess the biomechanical effects of wearing shoes while performing fundamental motor skills in children. Barefoot and shod conditions were tested in healthy children between the age of 4 and 7 years. They were asked to perform basic and advanced motor skills including double-leg stance, horizontal jumps, walking as well as counter-movement jumps, single-leg stance and sprinting. Postural control and ground reaction data were measured with two embedded force plates. A 3D motion capture system was used to analyse the spatiotemporal parameters of walking and sprinting. Findings showed that the parameters of single- and double-leg stance, horizontal and counter-movement jump did not differ between barefoot and shod conditions. Most of the spatiotemporal variables including cadence, stride length, stride time, and contact time of walking and sprinting were statistically different between the barefoot and shod conditions. Consequently, tested shoes did not change performance and biomechanics of postural control and jumping tasks; however, the spatiotemporal gait parameters indicate changes in walking and sprinting characteristics with shoes in children.
Cardiac remodeling in child and adolescent athletes in association with sport discipline and sex
(2020)
Continuous high training loads are associated with structural cardiac adaptations and development of an athletic heart in adult athletes, especially in sport disciplines with high dynamic training components. In child and adolescent athletes these effects are increasingly reported. However, study populations are still very small.
Objectives:
The prevalence rates for mental health (MH) problems in cancer patients is high, although reduced uptake of services may be influenced by mental health literacy (MHL). The objective of this study was to investigate the MHL for depression and panic disorder (PD), including treatment preferences in Australian adults who had been diagnosed and treated for cancer, and whether MHL and treatment preferences was influenced by sex, age, and individuals' lived MH experience.
Method:
A total of 421 cancer survivors (n = 378 females) completed a self-report survey. Participants were asked to specify whether they had a lived experience with anxiety and/or depression, and to indicate treatment preferences for managing cancer-related distress. Two vignettes were administered to assess MHL for depression and PD.
Results:
The MHL accuracy for depression was higher than PD. Accuracy rates were higher for females with a lived experience with anxiety and/or depression; although the accuracy rate for PD was significantly lower in males. A high proportion of individuals preferred exercise and in-person counselling to manage depression and PD. Internet-based therapies were not strongly preferred for managing MH problems.
Conclusions:
The MHL for depression and PD is moderate for adult cancer survivors, with higher levels indicated for individuals with a personal lived experience with anxiety and/or depression. Public health campaigns for enhancing MHL should broaden to include individuals experiencing comorbid physical health conditions. Health providers also need to take into account client preferences for evidence-based therapies.
PURPOSE: To determine the feasibility of upright compared to supine MRI measurements to determine characteristics of the lumbar spine in AA with spondylolisthesis.
METHODS: Ten AA (n=10; m/f: 4/6; 14.5±1.7y; 163±7cm; 52±8kg) from various sports, diagnosed with spondylolisthesis grade I-II Meyerding confirmed by x-ray in standing lateral view, were included. Open low-field MRI images (0.25 Tesla) in upright (82°) and supine (0°) position were evaluated by two observers. Medical imaging software was used to measure the anterior translation (AT, mm), lumbosacral joint angle (LSJA, °) and lordosis angle (LA, °). Reliability was analyzed by the intra-rater correlation coefficient (ICC) and standard error of measurements (SEM).
RESULTS: Due to motion artifacts during upright position, measures of three participants had to be excluded. Between observers, AT ranged from 4.2±2.7mm to 5.5±1.9mm (ICC=0.94, SEM=0.6mm) in upright and from 4.9±2.4mm to 5.9±3.0mm (ICC=0.89, SEM=0.9mm) in supine position. LSJA varied from 5.1±2.2° to 7.3±1.5° (ICC=0.54, SEM=1.5°) in upright and from 9.8±2.5° to 10±2.4° (ICC=0.73, SEM=1.1°) in supine position. LA differed from 58.8±14.6° to 61.9±6° (ICC=0.94, SEM=1.19°) in upright and from 51.9±11.7° to 52.6±11.1° (ICC=0.98, SEM=1.59°) in supine position.
CONCLUSIONS: Determination of AT and LA showed good to excellent reliability in both, upright and supine position. In contrast, reliability of LSJA had only moderate to good correlation
between observers and should therefore be interpreted with caution. However, motion artifacts should be taken into consideration during upright imaging procedures.
Coordination of the trunk and hips is crucial for successful dynamic balance in many activities of daily living. Persons with recurrent low back pain (rLBP), both while symptomatic and during periods of symptom remission, exhibit dysfunctional muscle activation patterns and coordination of these joints. In a novel dynamic balance task where persons in remission from rLBP exhibit dissociated trunk motion, it is unknown how trunk and hip musculature are coordinated. Activation of hip and trunk muscles were acquired from nineteen persons with and without rLBP during the Balance-Dexterity Task, which involves balancing on one limb while compressing an unstable spring with the other. There were no between-group differences in activation amplitude for any muscle groups tested. In back-healthy control participants, hip and trunk muscle activation amplitudes increased proportionally in response to the added instability of the spring (R = 0.837, p < 0.001). Increases in muscle activation amplitudes in the group in remission from rLBP were not proportional (R = 0.113, p = 0.655). Instead, hip muscle activation in this group was associated with task performance, i.e. dexterous control of the spring (R = 0.676, p = 0.002). These findings highlight atypical coordination of hip and trunk musculature potentially related to task demands in persons with rLBP even during remission from pain.
Core stability exercises are regular part of exercise programs for asymptomatic individuals across ages. The purpose of this study was to examine deep abdominal and multifidus muscle thickness in children and adults and to determine reliability of the rehabilitative ultrasound (RUSI) imaging. Transversus abdominis and lumbar multifidus thickness at rest and during core stability exercise were examined in pre-pubertal children (N = 23), adolescents (N = 20), young adults (N = 21) and middle-aged adults (N = 22). Thirty-nine participants were re-tested one week after to establish reliability. Muscle thickness at rest was lower in children and adolescents compared with young and middle-aged adults (p < 0.008). Young adults displayed the highest relative transversus abdominis thickness upon contraction (p < 0.008). Lumbar multfidus contraction thickness was greater in young-adults than middle-aged adults and prepubertal children (p < 0.008), but it was similar between young-adults and adolescents (p > 0.008). Reliability was high for both muscles (ICC3,3 = 0.76 - 0.99). The age-related differences in muscle thickness indicate that core stability exercises may be beneficial for children and middle-aged adults.
Field-based sports require athletes to run sub-maximally over significant distances, often while contending with dynamic perturbations to preferred coordination patterns. The ability to adapt movement to maintain performance under such perturbations appears to be trainable through exposure to task variability, which encourages movement variability. The aim of the present study was to investigate the extent to which various wearable resistance loading magnitudes alter coordination and induce movement variability during running. To investigate this, 14 participants (three female and 11 male) performed 10 sub-maximal velocity shuttle runs with either no weight, 1%, 3%, or 5% of body weight attached to the lower limbs. Sagittal plane lower limb joint kinematics from one complete stride cycle in each run were assessed using functional data analysis techniques, both across the participant group and within-individuals. At the group-level, decreases in ankle plantarflexion following toe-off were evident in the 3% and 5% conditions, while increased knee flexion occurred during weight acceptance in the 5% condition compared with unloaded running. At the individual-level, between-run joint angle profiles varied, with six participants exhibiting increased joint angle variability in one or more loading conditions compared with unloaded running. Loading of 5% decreased between-run ankle joint variability among two individuals, likely in accordance with the need to manage increased system load or the novelty of the task. In terms of joint coordination, the most considerable alterations to coordination occurred in the 5% loading condition at the hip-knee joint pair, however, only a minority of participants exhibited this tendency. Coaches should prescribe wearable resistance individually to perturb preferred coordination patterns and encourage movement variability without loading to the extent that movement options become limited.