Sports, Volume 8, Issue 2 (February 2020) – 16 articles

Interventions to promote physical activity (PA) in children, adolescents and young adults based on social-cognitive theories often fail to increase PA. In recent years, affect-based approaches have gained interest, but the current state of research is not sufficiently reported. Therefore, a systematic review about the influence of interventions to promote positive affect and PA enjoyment and PA in children, adolescents and young adults was conducted. Literature searches were carried out including studies published between September 2009 and April 2019. Intervention studies targeting healthy children, adolescents or young adults and measuring enjoyment and PA were included. Thirteen studies met the inclusion criteria, including five group-based PA interventions, three multi-component school interventions, two internet-based interventions and three exergaming interventions. Most studies use multiple components in their intervention. Group-based PA programs incorporating task-oriented teaching styles and opportunities for voluntary PA are most consistently associated with positive findings. This review shows moderate evidence of interventions for children, adolescents and young adults being effective in increasing enjoyment and PA. Besides physical education and comprehensive school interventions, heterogenous intervention designs limit the comparability of studies. Future research should focus on theory-based, multi-component interventions with mediator analyses. Full article

Prospective and retrospective studies have examined traumatic injuries within competitive and recreational surfers worldwide using online surveys and health care facility (HCF; e.g., hospital, emergency department, medical record) data. However, few studies have provided a synthesis of all available literature. The purpose of this study was to obtain, critique and synthesise all literature specific to acute surfing injuries, and evaluate differences in injury type, mechanism and location between HCF and survey data. A systematic literature review design was used to identify relevant articles from three major databases. Peer-reviewed epidemiological studies of musculoskeletal surfing injuries were included. A modified AXIS tool was used for critical appraisal, and objective data was extracted and synthesized by lead researchers. Overall frequencies for injury location, type and mechanism were calculated from raw injury data. A total of 19 cross-sectional articles of fair to good quality (Modified AXIS 54.2–83.3%) were included in this study; 17 were National Health and Medical Research Council (NHMRC) level III-2 (retrospective) and two were level II (prospective). Articles examined competitive, recreational and combined populations. Injury data from Australia, Brazil, UK, USA, Portugal, Japan, Norway, and worldwide were represented. Skin (46.0%; HCF 50.1%, survey 43.8%) and being struck by own surfboard (38.6%; HCF 73.4%, survey 36.7%) were the most common injury type and mechanism. Head, face and neck injuries were most common in HCF (43.1%) versus lower limb injuries (36.4%) in survey data. Incidence proportion was highest in aerialists (0.48). Incidence rate (number of injuries per 1000 h) ranged from 0.74 in Australian surfers (Melbourne) to 6.6 in international contest surfers from medical record data. This review highlights the prevalence of skin, board-related, head, face and neck, and lower limb surfing injuries across available literature. Proposed use of protective equipment and foam-based surfboards in dangerous or crowded surf locations may reduce injury risk. Full article

Background: Physiological and biomechanical parameters obtained during testing need validation in a training setting. The purpose of this study was to compare parameters calculated by a 5 × 200-m test with those measured during an intermittent swimming training set performed at constant speed corresponding to blood lactate concentration of 4 mmol∙L⁻¹ (V4). Methods: Twelve competitive swimmers performed a 5 × 200-m progressively increasing speed front crawl test. Blood lactate concentration (BL) was measured after each 200 m and V4 was calculated by interpolation. Heart rate (HR), rating of perceived exertion (RPE), stroke rate (SR) and stroke length (SL) were determined during each 200 m. Subsequently, BL, HR, SR and SL corresponding to V4 were calculated. A week later, swimmers performed a 5 × 400-m training set at constant speed corresponding to V4 and BL-5×400, HR-5×400, RPE-5×400, SR-5×400, SL-5×400 were measured. Results: BL-5×400 and RPE-5×400 were similar (p > 0.05), while HR-5×400 and SR-5×400 were increased and SL-5×400 was decreased compared to values calculated by the 5 × 200-m test (p < 0.05). Conclusion: An intermittent progressively increasing speed swimming test provides physiological information with large interindividual variability. It seems that swimmers adjust their biomechanical parameters to maintain constant speed in an aerobic endurance training set of 5 × 400-m at intensity corresponding to 4 mmol∙L⁻¹. Full article

(-)-Epicatechin is a polyphenol previously shown to enhance vascular health. The purposes of the current studies were to determine the effect of acute (-)-epicatechin supplementation on local vasodilation in conjunction with resistance exercise (study 1) and on high-intensity exercise performance (study 2). For study 1, 11 men participated in two resistance exercise sessions, where they performed three sets of barbell curls while consuming 200 mg of 98% pure (-)-epicatechin or placebo. Measurements of total serum nitrate/nitrite and brachial artery diameter were acquired at baseline (pre-supplement), 90 min after supplement consumption (post-supplement), immediately post-exercise (post-exercise), and 30 min post-exercise (30 min post-exercise). For serum nitric oxide metabolites, no significant interaction between supplement and time nor significant main effect of time was observed (p = 0.38 and p = 0.20; respectively). For brachial artery diameter, no significant interaction between supplement and time was observed (p = 0.24). A significant main effect of time was observed for brachial artery diameter (p < 0.01) with post-exercise brachial artery diameter significantly greater diameter than all other time points (all p < 0.01). For study 2, six women and five men completed the 15.5 CrossFit^® Open Workout three times. A familiarization session was performed first where the workout was performed without the consumption of a supplement. In a randomized, balanced fashion, 100 mg of 98% pure (-)-epicatechin or cellulose (placebo) was consumed two times per day for two days before testing sessions two and three. On the day of testing sessions two and three, 60 to 90 min before completing the workout, 200 mg of the assigned supplement was ingested with water. No significant difference was observed for time to complete the workout between testing sessions (p = 0.49). In conclusion, under the conditions of the current studies, acute (-)-epicatechin supplementation did not augment vasodilation in combination with resistance exercise, nor did it increase exercise performance in humans. Full article

Background: Previously published studies have reported injury rates ranging from 0.74 to 3.3 per 1000 h of exposure in CrossFit participants. However, the existing body of evidence is mainly based on experienced participants; therefore, the injury incidence and injury rate within novice CrossFit participants remains relatively unknown. The aim of this study wasto investigate the injury incidence and injury rate among novice participants in an eight-week CrossFit program. Methods: This survey-based prospective cohort study included CrossFit Copenhagen’s novice members who began an eight-week, free-of-charge membership period. A questionnaire was distributed at baseline and at eight-week follow-up. Information about exposure was retrieved through the online booking system. Injury incidence, defined as proportion of participants who sustained an injury, and injury rates per 1000 h of exposure were calculated. Results: Among the 168 included participants, a total of 28 injuries (14.9%) were reported. The number of injured participants and total exposure time resulted in an injury rate per 1000 h of exposure of 9.5. Conclusions: Compared to the existing body of evidence, the findings in this study indicate that the risk of injuries is higher among novice participants than among experienced CrossFit participants. Full article

Two decades ago, McKenzie’s meta-analysis of literature provided six fundamental elements of adventure education programme design still used to guide research and practice today. While the value of McKenzie’s early work should not be underestimated, adventure education has undergone considerable changes. Adventurous activities are now available in urban and indoor contexts and used to facilitate a growing health and wellbeing agenda. The use of risk as part of adventure education programming has also been critiqued. This paper reflects on contemporary notions of adventure, risk and the emergent narratives emphasising the associated psychological benefits. The Ecological Dynamics framework, along with representative design delivery, are presented as a viable way of building on McKenzie’s work. Both consider how effective outcomes in adventure education programmes are achieved through designs that focus on the unique relationship between the individual and their environment. While McKenzie’s six elements recognise the importance of human relationships, Ecological Dynamics forefronts relational elements, not just between participants but, importantly, the task and the environment. Individual participant needs in relation to their everyday life therefore become the focus of adventure education expanding beyond the traditional long-standing narratives of risk and danger. Through these two important concepts, this paper advocates an approach to the design of adventure representative of a participant’s everyday environment. In this way, adventure education outcomes translate beyond the adventure-specific context and align more holistically with the needs of individual participants while also assuring emphasis on individual health and wellbeing. Full article

The purpose of this study was to clarify whether there have been any specific changes in the characteristics of the world’s top-level women’s singles badminton matches compared to men’s singles matches after the current badminton scoring system was implemented in 2006. We compared the characteristics of the matches between the Super Series tournaments in 2007 and 2017. Match duration increased as the rally and rest times increased in both men’s and women’s singles matches. Specifically, in women’s singles, it was suggested that a further increase in physical demands because of the increased number of shots per second may have resulted in longer rest time in proportion to rally time. Moreover, increases in match duration (final eight, 53.3 ± 6.6 min; early rounds, 42.1 ± 3.6 min; P < 0.05) and number of shots per rally (final eight, 10.4 ± 1.2; early rounds, 8.7 ± 1.1; P < 0.05) in women’s singles were more prominent in the final eight rounds (quarterfinals, semifinals, and finals) than in the early rounds (rounds 1 and 2). The recent changes in characteristics of the world’s top-level badminton matches may account for the increased acute injuries that are frequently observed in elite women’s singles players. Thus, appropriate training programs are crucial to effectively improve performance and prevent injuries among elite badminton players. Full article

Despite the role of working memory capacity (WMC) in decision making, there is a dearth of empirical literature concerned with working memory and how it relates to tactical decision making in sport. The temporal occlusion paradigm has often been used by sport researchers to improve tactical decision making and, thus, provides a well-established foundation for creating decision-making trainings. Therefore, the purpose of the current study was to explore the implementation of computer-based learning modules to improve the tactical decision making of four high school quarterbacks with varying levels of WMC, utilizing a single-subject, multiple baseline design. The learning modules utilized a temporal occlusion paradigm and present a novel intervention aimed at improving decision making in quarterbacks. Data were analyzed using visual analysis and improvement rate difference (IRD). Overall, results did not demonstrate a causal relationship between changes in accuracy of decision making after implementation of the learning modules but did provide moderate evidence for improvement in reaction time for decision making due to the learning modules. The learning modules were met with positive perceptions from the four participants, and the participant with the lowest WMC showed evidence of improvement in both accuracy and speed of decision making. Limitations as well as implications will be discussed. Full article

External auditory exostosis (EAE) has previously only been shown to occur in cold water surfers. We assessed young surfers living and surfing in Queensland, Australia, for EAE in water temp ranges from 20.6 °C (69.1 °F, Winter) to 28.2 °C (82.8 °F, Summer). All participants underwent a bilateral otoscopic examination to assess the presence and severity of EAE. A total of 23 surfers participated with a mean age of 35.4 years (8.3 years) and a mean surfing experience of 20.0 years (9.9 years). Nearly two-thirds of participants (n = 14, 60.9%) had regular otological symptoms, most commonly water trapping (n = 13, 56.5%), pain (n = 8, 34.8%), and hearing loss (n = 6, 26.1%). Only 8.7% (n = 2) of all surfers reported regular use of protective equipment (e.g., earplugs) on a regular basis. The overall prevalence of exostosis was 69.6% (n = 16), and the majority (n = 12, 80.0%) demonstrated bilateral lesions of a mild grade (<33% obstruction of the external auditory canal). This is the first study assessing EAE in young surfers exposed to only warm waters (above 20.6 °C). The prevalence of EAE in this study highlights that EAE is not restricted to cold water conditions, as previously believed. Warm water surfing enthusiasts should be screened on a regular basis by their general medical practitioner and utilize prevention strategies such as earplugs to minimize exposure to EAE development. Full article

Background: This study aimed at comparing bioenergetics and biomechanical parameters between athletes with tetraplegia and paraplegia riding race handbikes at submaximal speeds in ecological conditions. Methods: Five athletes with tetraplegia (C6-T1, 43 ± 6 yrs, 63 ± 14 kg) and 12 athletes with paraplegia (T4-S5, 44 ± 7 yrs, 72 ± 12 kg) rode their handbikes at submaximal speeds under metabolic measurements. A deceleration method (coasting down) was applied to calculate the rolling resistance and frontal picture of each participant was taken to calculate air resistance. The net overall Mechanical Efficiency (Eff) was calculated by dividing external mechanical work to the corresponding Metabolic Power. Results: Athletes with tetraplegia reached a lower aerobic speed (4.7 ± 0.6 m s⁻¹ vs. 7.1 ± 0.9 m s⁻¹, P = 0.001) and Mechanical Power (54 ± 15 W vs. 111 ± 25 W, P = 0.001) compared with athletes with paraplegia. The metabolic cost was around 1 J kg⁻¹ m⁻¹ for both groups. The Eff values (17 ± 2% vs. 19 ± 3%, P = 0.262) suggested that the handbike is an efficient assisted locomotion device. Conclusion: Handbikers with tetraplegia showed lower aerobic performances but a similar metabolic cost compared with handbikers with paraplegia at submaximal speeds in ecological conditions. Full article

Acute exercise influences human cognition, and evidence suggests that learning can be improved. According to the cognitive–energetic approach towards exercise cognition, exercise represents a stressor that elevates physiological arousal, which, in turn, increases the availability of mental resources. However, the degree of arousal is hypothesized to have optimal and suboptimal states, and moderate intensity exercise is thus considered to be favorable compared to low intensity and vigorous exercise. The current evidence for such a moderating effect of exercise intensity on motor learning, however, appears somewhat mixed. Therefore, the purpose of this study was to explore the effect of aerobic exercise conducted with different exercise intensities on immediate practice, transfer, and 24-h retention of a motor skill. To this end, young adults (n  =  40, mean (SD) age: 23.80 (1.98) years) were randomized to exercise at either 50% or 75% of age-predicted maximal heart rate according to the Karvonen formulae. Immediately after exercising, participants practiced a high-precision golf putting task in a blocked design. Retention and transfer of skill were assessed after 24 h. Results indicated that both groups demonstrated motor learning, retention, and transfer at a similar level. Further works are thus needed to establish the specific relationship between exercise and learning and establish the factors that have an influence. Full article

The physical qualities that underpin successful junior judokas requires continuing investigation. We investigated the physical and physiological characteristics of junior national level judokas. We tested 25 (15 male, 10 female) Indian judokas for absolute and relative strength (back-squat and bench-press one-repetition maximum (1RM) as well as isometric handgrip), aerobic (RAMP test) and lower-body anaerobic power (Wingate 6-s sprint and countermovement jump), change-of-direction (5-0-5 test) and speed (30 m sprint). Athletes were grouped according to national-level competition placing (gold-medal winners (GM; n = 8), all medal winners (MW; n = 13), non-medallists (NM; n = 12), and NM plus silver and bronze; all others (AO; n = 17)). Stepwise discriminant function analysis determined characteristics likely to predict successful performance. Independent t-tests and effect size (Hedge’s g) analyses were performed between groups. GM demonstrated greater lower-body absolute (20.0%; g = 0.87, p = 0.046) and relative 1RM strength (21.0%; g = 0.87, p = 0.047), and greater lower-body absolute (25.4%; g=1.32, p=0.004) and relative (27.3%; g = 1.27, p = 0.005) anaerobic power compared to AO. Furthermore, anaerobic power can correctly predict 76.5% and 62.5% of AO and GM athletes, respectively. No differences were observed between MW and NM groups. The results suggest the importance of lower-body strength and power for junior national-level judokas and provides information for professionals working with these athletes. Full article

This double-blind study examined effects of a protease enzyme blend (Prohydrolase^®) added to whey protein on post-resistance exercise aminoacidemia and intramuscular anabolic signaling were investigated in ten resistance-trained males. Participants completed 4 sets of 8–10 repetitions in the leg press and leg extension exercises at 75% of 1-repetition maximum. Participants then consumed either 250 mg of Prohydrolase^® + 26 g of whey protein (PW), 26 g whey alone (W), or non-nutritive control (CON) in counterbalanced order. Blood samples were obtained prior to exercise (baseline) and then immediately-post (IP), 30-, 60-, 90-, 120-, and 180-min post-exercise. Muscle biopsies were taken at baseline, 1-h (1H), and 3-h (3H) post-exercise. Phosphorylation of AKT^Ser437 was decreased (3H only: p < 0.001), mTOR^Ser2448 was increased (1H: p = 0.025; 3H: p = 0.009), and p70S6K^Thr412 remained unchanged similarly for each condition. Plasma leucine, branch-chained amino acids, and essential amino acid concentrations for PW were significantly higher than CON (p < 0.05) at 30 min and similar to W. Compared to IP, PW was the only treatment with elevated plasma leucine levels at 30 min (p = 0.007; ∆ = 57.8 mmol/L, 95% Confidence Interval (CI): 20.0, 95.6) and EAA levels at 180 min (p = 0.003; ∆ = 179.1 mmol/L, 95% CI: 77.5, 280.7). Area under the curve amino acid analysis revealed no differences between PW and W. While no different than W, these data indicate that PW was the only group to produce elevated amino acid concentrations 30-min and 180-min post-ingestion. Full article

We aimed to determine whether creatine supplementation influences lower-limb muscle endurance following an acute bout of aerobic exercise (AE) in young healthy men. Using a randomized, double-blind, placebo-controlled crossover design, 11 men (26.5 ± 6.2 years, body mass index 26.6 ± 2.1 kg/m²),with 12 months of experience in strength training (three times/week) and AE (two times/week) were randomized to receive creatine (20 g/day plus 20 g/day maltodextrin) and placebo (40 g/day maltodextrin) for 7 days, separated by a washout period of 14 days, before performing an acute bout of AE (30 min on treadmill at 80% baseline maximum velocity) which was followed by four sets of bilateral leg extension endurance exercise using a 10-repetition maximum protocol (10 RM)). There was a significant decrease in the number of repetitions performed in the third (Placebo: −20% vs. Creatine: −22%) and fourth set (Placebo: −22% vs. Creatine: −28%) compared with the first set (p < 0.05), with no differences between creatine and placebo. Additionally, no differences were observed between creatine and placebo for the total number of repetitions performed across all four sets (Placebo: 33.9 ± 7.0 vs. Creatine: 34.0 ± 6.9 repetitions, p = 0.97), nor for total work volume (Placebo: 3030.5 ± 1068.2 vs. Creatine: 3039.8 ± 1087.7 kg, p = 0.98). Short-term creatine supplementation has no effect on lower-limb muscle endurance following an acute bout of aerobic exercise in trained young men. Full article

This study examined the effects of the Badminton World Federation (BWF) Shuttle Time program on fundamental movement skills (FMS) in English children. A total of 124 children; 66 in key stage 1 (ages 6–7 years) and 58 in key stage 2 (10–11 years) undertook the Shuttle Time program, once weekly for six weeks (n = 63) or acted as controls (n = 61). Pre, post and ten-weeks post, both process and product FMS were determined. Children in the intervention group, aged 6–7 years, had higher total process FMS (via test of gross motor development-2) compared to the control group at post and ten-weeks post intervention (both p = 0.0001, d = 0.6 and 0.7, respectively). There were no significant differences in process FMS scores for children aged 10–11 years. Ten-meter sprint speed decreased pre to post and was maintained at ten-weeks post for the intervention groups aged 6–7 years (p = 0.0001, d = 0.6) and 10–11 years (p = 0.001, d = 0.2) compared to control. Standing long jump distance increased pre to post (p = 0.0001, d = 0.8) and was maintained at ten-weeks post (p = 0.0001, d = 0.5) for the intervention group. Medicine ball throw performance increased pre to post (p = 0.0001, d = 0.3) for the intervention group. The BWF Shuttle Time program is beneficial in developing FMS for key stage 1 children (ages 6–7). Full article