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David C. Nieman, Francesca Ferrara, Alessandra Pecorelli, Brittany Woodby, Andrew T. Hoyle, Andrew Simonson and Giuseppe Valacchi

Inflammasomes are multiprotein signaling platforms of the innate immune system that detect markers of physiological stress and promote the maturation of caspase-1 and interleukin 1 beta (IL-1β), IL-18, and gasdermin D. This randomized, cross-over trial investigated the influence of 2-week mixed flavonoid (FLAV) versus placebo (PL) supplementation on inflammasome activation and IL-1β and IL-18 production after 75-km cycling in 22 cyclists (42 ± 1.7 years). Blood samples were collected before and after the 2-week supplementation, and then 0 hr, 1.5 hr, and 21 hr postexercise (176 ± 5.4 min, 73.4 ± 2.0 %VO2max). The supplement (678 mg FLAVs) included quercetin, green tea catechins, and bilberry anthocyanins. The pattern of change in the plasma levels of the inflammasome adaptor oligomer ASC (apoptosis-associated speck-like protein containing caspase recruitment domain) was different between the FLAV and PL trials, with the FLAV ASC levels 52% lower (Cohen’s d = 1.06) than PL immediately following 75-km cycling (interaction effect, p = .012). The plasma IL-1β levels in FLAV were significantly lower than PL (23–42%; Cohen’s d = 0.293–0.644) throughout 21 hr of recovery (interaction effect, p = .004). The change in plasma gasdermin D levels were lower immediately postexercise in FLAV versus PL (15% contrast, p = .023; Cohen’s d = 0.450). The patterns of change in plasma IL-18 and IL-37 did not differ between the FLAV and PL trials (interaction effects, p = .388, .716, respectively). These data indicate that 2-week FLAV ingestion mitigated inflammasome activation, with a corresponding decrease in IL-1β release in cyclists after a 75-km cycling time trial. The data from this study support the strategy of ingesting high amounts of FLAV to mitigate postexercise inflammation.

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Marco J. Konings and Florentina J. Hettinga

Purpose: The behavior of an opponent has been shown to alter pacing and performance. To advance our understanding of the impact of perceptual stimuli such as an opponent on pacing and performance, this study examined the effect of a preexercise cycling protocol on exercise regulation with and without an opponent. Methods: Twelve trained cyclists performed 4 experimental, self-paced 4-km time-trial conditions on an advanced cycle ergometer in a randomized, counterbalanced order. Participants started the time trial in rested state (RS) or performed a 10-min cycling protocol at 67% peak power output (CP) before the time trial. During the time trials, participants had to ride alone (NO) or against a virtual opponent (OP). The experimental conditions were (1) RS-NO, (2) RS-OP, (3) CP-NO, and (4) CP-OP. Repeated-measures analyses of variance (P < .05) were used to examine differences in pacing and performance in terms of power output. Results: A faster pace was adopted in the first kilometer during RS-OP (318 [72] W) compared with RS-NO (291 [81] W; P = .03), leading to an improved finishing time during RS-OP compared with RS-NO (P = .046). No differences in either pacing or performance were found between CP-NO and CP-OP. Conclusions: The evoked response by the opponent to adopt a faster initial pace in the 4-km time trial disappeared when cyclists had to perform a preceding cycling protocol. The outcomes of this study highlight that perceived exertion alters the responsiveness to perceptual stimuli of cyclists during competition.

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Christanie Monreal, Lindsay Luinstra, Lindsay Larkins and James May

Context: Technological advances have given smartphones the capabilities of sensitive clinical measurement equipment at lesser cost and higher availability. The Clinometer is a smartphone application that can be used to measure the joint range of motion in a clinical setting, but psychometric properties of the tool’s use measuring cervical range of motion (CROM) are not established. Objectives: The purpose of this study was to examine the validity and intrarater reliability of the Clinometer application for the measurement of CROM (ie, flexion, extension, rotation, lateral flexion) and to determine the minimal detectable change and SEM. Design: A blinded, repeated-measures correlational design was employed. Setting: The study was conducted collaboratively between 2 athletic training clinics. Participants: A convenience sample of healthy adults ages 18–30 years were recruited. Participants with any history in the last 3 months of cervical or thoracic pathology, pain, or any musculoskeletal injury were excluded. Main Outcome Measures: Three repetitions of each motion were measured by a primary researcher with a goniometer. The same researcher then conducted 3 blinded measurements with the Clinometer application following the same procedure. A second researcher, blinded to the goniometer measurements, recorded the results. Thirty minutes later, testing was repeated with the application. The Pearson correlation was calculated to determine validity of the application compared with goniometry. Results: The measurements between devices had moderate to excellent concurrent validity, with the coefficients ranging between 0.544 and 0.888, P < .01. Test–retest reliability of the CROM measurement using the application was moderate to excellent, with intraclass correlation coefficients ranging between .774 and .928. Across all movements, the SEM ranged from 1.17° to 2.01°, and the minimal detectable change ranged from 1.18° to 2.02°. Conclusion: The Clinometer application is a valid and reliable instrument for measuring active CROM. Level of evidence: clinical measurement, level 1b.

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Ben Langley, Nick Knight and Stewart C. Morrison

Medial tibial stress syndrome (MTSS) is a common running-related injury. Alterations in movement patterns and movement coordination patterns have been linked to the development of overuse injuries. The aim of this study was to compare transverse plane tibial and frontal plane rearfoot motion and the coordination of these movements between runners with MTSS and healthy controls. A total of 10 recreational runners with MTSS and 10 healthy controls ran at 11 km/h on a treadmill. A 3-camera motion analysis system operating at 200 Hz was used to calculate tibia and rearfoot motion. Stance phase motion patterns were compared between groups using multivariate analysis, specifically, Hotelling T 2 test with statistical parametric mapping. A modified vector coding technique was used to classify the coordination of transverse plane tibial and frontal plane rearfoot motion. The frequency of each coordination pattern displayed by each group was compared using independent samples t tests. Individuals with MTSS displayed significantly (P = .037, d = 1.00) more antiphase coordination (tibial internal rotation with rearfoot inversion) despite no significant (P > .05) differences in stance phase kinematics. The increased antiphase movement may increase the torsional stress placed upon the medial aspect of the tibia, contributing to the development of MTSS.

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Ryan Zerega, Carolyn Killelea, Justin Losciale, Mallory Faherty and Timothy Sell

Rupture of the anterior cruciate ligament (ACL) remains extremely common, with over 250,000 injuries annually. Currently, clinical tests have poor utility to accurately screen for ACL injury risk in athletes. In this study, the position of a knee marker was tracked in 2-dimensional planes to predict biomechanical variables associated with ACL injury risk. Three-dimensional kinematics and ground reaction forces were collected during bilateral, single-leg stop-jump tasks for 44 healthy male military personnel. Knee marker position data were extracted to construct 2-dimensional 95% prediction ellipses in each anatomical plane. Knee marker variables included: ellipse areas, major/minor axes lengths, orientation of ellipse axes, absolute ranges of knee position, and medial knee collapse. These variables were then used as predictor variables in stepwise multiple linear regression analyses for 7 biomechanical variables associated with ACL injury risk. Knee flexion excursion, normalized peak vertical ground reaction forces, and knee flexion angle at initial contact were the response variables that generated the highest adjusted R 2 values: .71, .37, and .31, respectively. The results of this study provide initial support for the hypothesis that tracking a single marker during 2-dimensional analysis can accurately reflect the information gathered from 3-dimensional motion analysis during a task assessing knee joint stability.

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Janet Lok Chun Lee and Rainbow Tin Hung Ho

In response to demographic changes in recent years, an increasing number of parks have established exercise spaces for older adults. However, limited research has been conducted to investigate how older adults utilize, experience, and perceive these spaces. This study aims to explore their experiences of using these spaces and their perspectives on these spaces by using a qualitative descriptive research design. In-depth interviews were conducted with 32 users in three Hong Kong parks with low, medium, and high area-based socioeconomic statuses. The findings highlight that exercise spaces in parks can cultivate a positive environment allowing older adults with varying physical abilities and health statuses to remain active together as well as to support each other socially and emotionally in a natural outdoor setting. The participants’ perspectives on the exercise space discussed in this study suggest that future plans for constructing such spaces in parks might benefit from a co-design approach.

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Kimberly Bigelow and Michael L. Madigan

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Stuart A. McErlain-Naylor

The aim of this study was to investigate student experiences of publishing undergraduate research in biomechanics. A total of 29 former students with experience of publishing peer-reviewed undergraduate biomechanics research completed an online survey regarding their perceived benefits, level of involvement, and experiences in aspects of the research process. On average, students perceived their experiences to be “largely helpful” or greater in all aspects. Areas were identified corresponding to: the greatest perceived benefits (eg, understanding of the research process); the least perceived benefits (eg, statistical analysis skills); the greatest student involvement (eg, reading relevant literature); and the least student involvement (eg, developing hypotheses and/or methods). A thematic analysis of open question responses identified themes relating to: future career, skills, scientific process, intra- and interpersonal factors, and pedagogy. Common intended learning outcomes may be achieved through involvement in the research process independently of the level of staff involvement. Staff should be encouraged to involve students in publishable biomechanics research projects where this is possible without compromising research standards and should explore ways of recreating the publishing process internally for all students.

Open access

Nicole K. Nathan, Rachel L. Sutherland, Kirsty Hope, Nicole J. McCarthy, Matthew Pettett, Ben Elton, Rebecca Jackson, Stewart G. Trost, Christophe Lecathelinais, Kathryn Reilly, John H. Wiggers, Alix Hall, Karen Gillham, Vanessa Herrmann and Luke Wolfenden

Aim: To assess the impact of a multistrategy intervention designed to improve teachers’ implementation of a school physical activity (PA) policy on student PA levels. Methods: A cluster-randomized controlled trial was conducted in 12 elementary schools. Policy implementation required schools to deliver 150 minutes of organized PA for students each week via physical education, sport, or class-based activities such as energizers. Schools received implementation support designed using the theoretical domains framework to help them implement the current policy. Results: A total of 1,502 children in kindergarten to grade 6 participated. At follow-up compared with control, students attending intervention schools had, measured via accelerometer, significantly greater increases in school day counts per minute (97.5; 95% confidence interval [CI], 64.5 to 130.4; P < .001) and moderate to vigorous physical activity (MVPA) (3.0; 95% CI, 2.2–3.8, P < .001) and a greater decrease in sedentary time (−2.1; 95% CI, −3.9 to −0.4, P = .02) per school day. Teachers in intervention schools delivered significantly more minutes (36.6 min) of PA to their students at follow-up (95% CI, 2.7–70.5, P = .04). Conclusions: Supporting teachers to implement a PA policy improves student PA. Additional strategies may be needed to support teachers to implement activities that result in larger gains in student MVPA.

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John Stoszkowski, Áine MacNamara, Dave Collins and Aran Hodgkinson

Recent developments have seen a growth in coaching, with an associated boom in interest on how it may be optimised. Clearly, the authors applaud this evolution. This growth has been parallelled by an explosion in the availability of information, driven through Internet access and the phenomenon of social media. Unfortunately, however, this juxtaposition of interest and availability has not been matched by the application or exercise of effective quality control. While much of what is available is well intentioned, a tendency for poor quality and possibly less positively targeted “bullshit” has also arisen. In this insights paper, the authors have considered some of the reasons why and argued that an emphasis on the development of critical and analytical thinking, as well as a scepticism towards the sources of information, would be a positive step against coach susceptibility to bullshit. In doing so, and to encourage more critical consumption of the “knowledge” available, the authors presented a checklist to help coaches assess the veracity of claims and sift through the noise of the coaching landscape.