Journal of Sports Sciences

This study investigated physical activity (PA) levels among adolescents and their parents in South Korea. Repeated cross-sectional data from 2017-2019 Korea National Health and Nutrition Examination Survey (KNHANES) were used. The KNHANES uses a complex, multi-stage probability sample design. Data included 875 Korean adolescents aged 12 to 18years and their parents. Adolescents were asked how many days during the week they were physically active for at least 60 minutes. Compliance was defined as 4+ days per week...

Repeated sprint ability (RSA) is more closely related to match performance outcomes than single-sprint performance, but the kinetic determinants in youth athletes remain poorly understood. Therefore, the aim of the study was to explore the kinetic determinants of RSA in youth athletes. Twenty trained adolescents (15 girls; 14.4 ± 1.0 years) completed five 15 m repetitions interspersed with 5-s rest. Velocity was measured during each trial using a radar gun at >46 Hz, following which the force-velocity-power (F-v-P) profile was fitted to a velocity-time curve and instantaneous power and force variables calculated...

We attempted to find a subset model that would allow robust prediction of a swimmer's vertical body position during front crawl with fewer markers, which can reduce extra drag and time-consuming measurements. Thirteen male swimmers performed a 15-metre front crawl either with three different lung-volume levels or various speeds, or both, without taking a breath with 36 reflective markers. The vertical positions of the centre of mass (CoM) and four representative landmarks in the trunk segment over a stroke cycle were calculated using an underwater motion-capture system...

Achilles tendinopathy was reported to have the highest incidence proportion of all running-related injuries. The purpose of this study was to analyse the association between the Achilles tendon structure and running activity status. 350 healthy participants (runners and inactive controls, 30-50 years) participated in this research. Each participant completed questionnaires: socioeconomic, psychological, physical activity habits, running status and history and VISA-A. Magnetic resonance imaging, anthropological, running biomechanics and 14 days of physical activity monitoring assessments were performed...

This case study reports on a professional football player (age: 17.6 years) who was referred for sleep monitoring and intervention after reporting excessive night-time awakenings. The player undertook a series of subjective sleep assessments and objective sleep monitoring (activity monitor). Based on the data presented, a sleep hygiene intervention was prescribed. Numerical comparisons were made between pre-intervention (Pre) and post-intervention (Post) values. Objective values were also compared to reference data from a similarly aged professional cohort from the same club ( n  = 11)...

To determine whether the association between self-reported walking pace and all-cause mortality (ACM) persists across categories of accelerometer-assessed physical activity status. Data from 93,709 UK Biobank participants were included. Physical activity was assessed using wrist-worn accelerometers for 7-days. Participants accumulating <150 min/week moderate-to-vigorous- activity were classed as "inactive", ≥150 min/week moderate (≥3 METs) activity as "somewhat active" excluding those with ≥150 min/week upper-moderate-to-vigorous activity (≥4...

Lower-limb wearable resistance (WR) facilitates targeted resistance-based training during sports-specific movement tasks. The purpose of this study was to determine the effect of two different WR placements (thigh and shank) on joint kinematics during the acceleration phase of sprint running. Eighteen participants completed maximal effort sprints while unloaded and with 2% body mass thigh- or shank-placed WR. The main findings were as follows: 1) the increase to 10 m sprint time was small with thigh WR (effect size [ES] = 0...

Surfing has become a popular, non-age dependent sport that can be performed at most beaches. Hence, coaches and athletes have recognised the importance of physical preparation to enhance athletic performance. The purpose of this study was to investigate the effects of a sport-specific, land-based-home exercise programme (LB-HEP) on sport-specific assessments related to surfing performance in recreational surfers. Twenty-two year-round recreational surfers divided into two groups: the exercise group (EG) performed the LB-HEP 3 times a week for 8 weeks while the control group (CG) maintained their current exercise...

The aim of the study was to examine the birth quartile and maturity status distributions of male academy cricketers. Participants included 213 junior cricket players, aged between 9 and 18 years. Players were separated into birth quartiles and also grouped as early, average or late maturers. For the whole cohort, there was a medium effect bias towards players born in BQ1, but the number of early, average and late maturers was as expected. However, there were significantly more early maturers in the U10 and U11 groups than expected, and maturity distributions of the BQ groups showed that there was a small effect size bias towards early maturers in BQ4...

Irrational beliefs are a risk factor for mental ill-health and exercise dependence. In addition to this, researchers have also proposed that body image inflexibility can determine mental health and behavioural outcomes. However, research is yet to explore whether and to what extent irrational beliefs and body image inflexibility align to influence mental health and exercise dependence. We examined the latent profile structure of irrational beliefs and body image inflexibility, and how these latent profiles relate to mental health and exercise dependence in exercise active adults...

The National Football League (NFL) Combine provides NFL teams the ability to assess prospective athletes' medical histories and physical and psychological abilities. Using this information, NFL personnel must then decide whether an athlete is a good fit to their team. Given the combine's 40-year history and the availability of peer reviewed articles on the function and efficacy of the combine, the purpose of this systematic review was to synthesize the literature evaluating the predictive validity of the combine according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses)...

The relationships between movement style and golf performance have been well researched, but the premise of segregated movement styles has not been fully examined. The purpose of this investigation was to examine the postulation that centre of pressure data are not best described by segregated styles but instead by a continuum and to determine relationships between centre of pressure, handicap and clubhead speed using a continuous approach. Centre of pressure paths of driver and 5-iron shots from 104 amateur golfers were analysed using discrete and continuous methods...

In this study, we investigated the relationship between age and performance in professional road cycling. We considered 1864 male riders present in the yearly top 500 ranking of ProCyclingStats (PCS) since 1993 until 2021 with more than 700 PCS Points. We applied a data-driven approach for finding natural clusters of the rider's speciality (General Classification, One Day, Sprinter or All-Rounder). For each cluster, we divided the riders into the top 50% and bottom 50% based on their total number of PCS points...

Psychological Characteristics of Developing Excellence (PCDEs) are a range of psychological factors that play a key role in the realisation of potential. We examined PCDE profiles across a female national talent development field hockey programme in North America. Two-hundred-and-sixty-seven players completed the Psychological Characteristics of Developing Excellence Questionnaire version 2 (PCDEQ-2) prior to the competitive season. One-hundred-and-fourteen players were classified as juniors (under-18) and 153 as seniors (over-18)...

This systematic review and meta-analysis investigated the benefits, safety and adherence of exercise interventions delivered in inpatient mental health settings, quantified the number of exercise trials that provided support to maintain engagement in exercise post-discharge, and reported patient feedback towards exercise interventions. Major databases were searched from inception to 22.06.2022 for intervention studies investigating exercise in mental health inpatient settings. Study quality was assessed using Cochrane and ROBINS-1 checklists...

The current study evaluated longitudinal associations between profile transitions of context-specific sedentary behaviour (SB) and changes in academic performance (AP) among school-aged youth. Participants were 466 children and 717 adolescents (50.8% males) aged 8-18 years (children = 7.92 ± 0.41 years; adolescents = 11.85 ± 1.53 years). Non-school SBs and AP were evaluated at baseline and two years later. General linear mixed models were implemented, controlling for age, region, parental education, body mass index, and cardiorespiratory fitness...

This study examined the association between team performance perceived by coaches, coaches' basic psychological needs, motivation, and their intentions to persist in coaching. Participants were 719 coaches (80 females, M  = 33.49 years, SD = 10.27, range = 18-67) of different team sports (soccer = 514; basketball = 165; volleyball = 23; handball = 14; and hockey = 3) who completed questionnaire measures at the end of the season...

The purposes of this study were to investigate the acute effects of resistance training protocol on kinetic changes in squat jump (SJ), shortened isometric mid-thigh pull (IMTP), and isometric squat (ISQ) and to examine the relationship of dynamic maximum strength with performance changes over 48 hours in resistance-trained individuals. Participants completed performance tests at pre-, post-24 hours, and post-48 hours resistance training protocol (Baseline, Post24, and Post48). The training protocol consisted of 5 sets of 10 repetitions of back squat (BSQ) at 60% of 1 repetition maximum (1RM)...

This study analysed the extent to which player performance differs within the Australian Football League (AFL) with respect to the status of a player's contract. AFL Player Ratings (AFLPR) and contract data were obtained during the 2013-2020 AFL seasons for all 827 players listed by an AFL club at the beginning of the 2020 season. A model of "expected performance" was created allowing for an exploration into the differential with actual performance as a function of contract status. Paired t-tests indicated that there was a difference in performance pre- and post-signing their contract for players who signed mid-season (mean change and 95% confidence interval of -1...

The present longitudinal meta-analysis aimed to estimate the growth curves and age at peak height velocity (PHV) in young male athletes, considering anthropometric data from available longitudinal studies. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, studies with repeated measurements in young male athletes were identified from searches across four databases (MEDLINE, SPORTDiscus, Web of Science, and SCOPUS). Estimations were based on multilevel polynomial models using a fully Bayesian framework...