The Association Between the Acute:Chronic Workload Ratio and Running-Related Injuries in Dutch Runners: A Prospective Cohort Study.

OBJECTIVE: To investigate the association between the acute:chronic workload ratio (ACWR) and running-related injuries (RRI). METHODS: This is a secondary analysis using a database composed of data from three studies conducted with the same RRI surveillance system. Longitudinal data comprising running exposure (workload) and RRI were collected biweekly during the respective cohorts' follow-up (18-65 weeks). ACWR was calculated as the most recent (i.e., acute) external workload (last 2 weeks) divided by the average external (i.e., chronic) workload of the last 4, 6, 8, 10 and 12 weeks. Three methods were used to calculate the ACWR: uncoupled, coupled and exponentially weighted moving averages (EWMA). Bayesian logistic mixed models were used to analyse the data. RESULTS: The sample was composed of 435 runners. Runners whose ACWR was under 0.70 had about 10% predicted probability of sustaining RRI (9.6%; 95% credible interval [CrI] 7.5-12.4), while those whose ACWR was higher than 1.38 had about 1% predicted probability of sustaining RRI (1.3%; 95% CrI 0.7-1.7). The association between the ACWR and RRI was significant, varying from a small to a moderate association (1-10%). The higher the ACWR, the lower the RRI risk. CONCLUSIONS: The ACWR showed an inversely proportional association with RRI risk that can be represented by a smooth L-shaped, second-order, polynomial decay curve. The ACWR using hours or kilometres yielded similar results. The coupled and uncoupled methods revealed similar associations with RRIs. The uncoupled method presented the best discrimination for ACWR strata. The EWMA method yielded sparse and non-significant results.

Preventing injuries among recreational adult volleyball players: Results of a prospective randomised controlled trial.

The objective was to evaluate the effectiveness of an exercise-based warm-up programme ("VolleyVeilig") on the one-season occurrence of musculoskeletal injuries among recreational adult volleyball players. A prospective randomised controlled trial was conducted over the 2017-2018 volleyball season. Recreational adult volleyball players were allocated either to an intervention or control group. The Dutch version of the Oslo Sports Trauma Research Centre questionnaire was used to register and monitor acute and overuse injuries. A total of 672 volleyball players were enrolled: 348 in the intervention group (mean age: 30) and 324 in the control group (mean age: 27). The incidence rate of acute injury was 21% lower in the intervention group, namely 8.9 versus 11.3 per 1,000 h in the control group (Cox mixed effects crude model: hazard ratio = 0.82 [95%CI: 0.69-0.98]; Cox mixed effects adjusted model: 0.85 [95%CI: 0.71-1.02]). No significant difference in mean prevalence of overuse injury was found between the intervention (4.8%) and control (4.2%) groups. The severity of injuries was not significantly different between groups, while injury burden was slightly lower in the intervention group. The exercise-based warm-up programme led to a trend in less acute injuries among recreational adult volleyball players.

A Warm-Up Program to Reduce Injuries in Youth Field Hockey Players: A Quasi-Experiment.

CONTEXT: Field hockey is popular worldwide; however, it entails a risk of injury. Injuries hamper players' participation in the sport and impose a burden on public health. OBJECTIVE: To investigate the effectiveness of a structured exercise program among youth field hockey players on the injury rate, severity, and burden. DESIGN: Quasi-experimental study. SETTING: On field during 1 season of field hockey (October 2016 through June 2017). PATIENTS OR OTHER PARTICIPANTS: A convenience sample of 22 teams (291 players): 10 teams (135 players, mean age = 11.5 years [95% confidence interval (CI) = 11.2, 11.7 years]) in the intervention group and 12 teams (156 players, mean age = 12.9 years [95% CI = 12.6, 13.2 years]) in the control group. INTERVENTION(S): The Warming-up Hockey program, a sex- and age-specific, structured, evidence-informed warm-up program consisting of a preparation phase (ie, agility and cardiovascular warm-up exercises), movement skills (ie, stability and flexibility exercises), and sport-specific skills (ie, speed and strength exercises in field hockey situations). Participants in the control group performed their usual warm-up routines. MAIN OUTCOME MEASURE(S): Injury rate (ie, the number of injuries per 1000 player-hours of field hockey exposure), severity (ie, days of player time-loss), and burden on athletes' availability to play (ie, days of time loss due to injury per 1000 player-hours of field hockey exposure). RESULTS: The injury rate was lower in the intervention group (hazard ratio of 0.64 [95% CI = 0.38, 1.07]); however, this result was not statistically significant. The severity of injuries was similar in both groups (t statistic P = .73). The burden of injuries on players' field hockey participation was lower in the intervention group (difference of 8.42 [95% CI = 4.37, 12.47] days lost per 1000 player-hours of field hockey). CONCLUSIONS: Exposure to the Warming-up Hockey program was not significantly associated with a lower injury rate. No reduction was observed in the severity of injuries alone; however, the burden of injuries on players' field hockey participation was lower in the intervention group.

Correction to: Injuries in Field Hockey Players: A Systematic Review.

Page 1: The listing of the author names and affiliations, which previously read.

Injuries in Field Hockey Players: A Systematic Review.

BACKGROUND: To commence injury prevention efforts, it is necessary to understand the magnitude of the injury problem. No systematic reviews have yet investigated the extent of injuries in field hockey, despite the popularity of the sport worldwide. OBJECTIVE: Our objective was to describe the rate and severity of injuries in field hockey and investigate their characteristics. METHODS: We conducted electronic searches in PubMed, Embase, SPORTDiscus, and CINAHL. Prospective cohort studies were included if they were published in English in a peer-reviewed journal and observed all possible injuries sustained by field hockey players during the period of the study. RESULTS: The risk of bias score of the 22 studies included ranged from three to nine of a possible ten. In total, 12 studies (55%) reported injuries normalized by field hockey exposure. Injury rates ranged from 0.1 injuries (in school-aged players) to 90.9 injuries (in Africa Cup of Nations) per 1000 player-hours and from one injury (in high-school women) to 70 injuries (in under-21 age women) per 1000 player-sessions. Studies used different classifications for injury severity, but-within studies-injuries were included mostly in the less severe category. The lower limbs were most affected, and contusions/hematomas and abrasions were common types of injury. Contact injuries are common, but non-contact injuries are also a cause for concern. CONCLUSIONS: Considerable heterogeneity meant it was not possible to draw conclusive findings on the extent of the rate and severity of injuries. Establishing the extent of sports injury is considered the first step towards prevention, so there is a need for a consensus on injury surveillance in field hockey.

Photobiomodulation therapy for the improvement of muscular performance and reduction of muscular fatigue associated with exercise in healthy people: a systematic review and meta-analysis.

Researches have been performed to investigate the effects of phototherapy on improving performance and reduction of muscular fatigue. However, a great variability in the light parameters and protocols of the trials are a concern to establish the efficacy of this therapy to be used in sports or clinic. The aim of this study is to investigate the effectiveness, moment of application of phototherapy within an exercise protocol, and which are the parameters optimally effective for the improvement of muscular performance and the reduction of muscular fatigue in healthy people. Systematic searches of PubMed, PEDro, Cochrane Library, EMBASE, and Web of Science databases were conducted for randomized clinical trials to March 2017. Analyses of risk of bias and quality of evidence of the included trials were performed, and authors were contacted to obtain any missing or unclear information. We included 39 trials (861 participants). Data were reported descriptively through tables, and 28 trials were included in meta-analysis comparing outcomes to placebo. Meta-analysis was performed for the variables: time until reach exhaustion, number of repetitions, isometric peak torque, and blood lactate levels showing a very low to moderate quality of evidence and some effect in favor to phototherapy. Further investigation is required due the lack of methodological quality, small sample size, great variability of exercise protocols, and phototherapy parameters. In general, positive results were found using both low-level laser therapy and light-emitting diode therapy or combination of both in a wavelength range from 655 to 950 nm. Most of positive results were observed with an energy dose range from 20 to 60 J for small muscular groups and 60 to 300 J for large muscular groups and maximal power output of 200 mW per diode.

Acceptability and perceptions of end-users towards an online sports-health surveillance system.

AIM: To describe the acceptability and the perceptions of athletes and staff members (ie, end-users) towards an online sports-health surveillance system. METHODS: A pilot study with a mixed-methods approach was pursued. Descriptive analysis was conducted to present the adherence of judo (n=34), swimming (n=21) and volleyball (n=14) athletes to an online registration of their sport exposure and any health complaints between April 2014 and January 2015. End-users' perceptions towards the system were investigated qualitatively with semistructured interviews (n=21). Qualitative analysis was based on the constant comparative method using principles of the grounded theory. RESULTS: The response rates of judo, swimming and volleyball athletes were 50% (SD 23), 61% (SD 27) and 56% (SD 25), respectively. Most athletes found it simple to register their sport exposure and health complaints online; however, personal communication was still preferred for this purpose. The system facilitated the communication between medical and trainer staff, who were able to identify in the system reports health complaints from athletes that were not necessarily communicated face-to-face. Therefore, staff members reported that they were able to intervene earlier to prevent minor health complaints from becoming severe health problems. However, staff members expected higher adherence of athletes to the online follow-ups, and athletes expected to receive feedback on their inputs to the system. CONCLUSION: An online system can be used in sporting settings complementary to regular strategies for monitoring athletes' health. However, providing feedback on athletes' inputs is important to maintain their adherence to such an online system.

Dieta elevada em carboidratos complexos minimiza necessidade de suplementação durante jogo-treino de rúgbi: foco no sistema imune / Diet high in complex carbohydrates minimizes necessity for supplementation during rugby training game: focus on immune system / Una dieta elevada en hidratos de carbono complejos minimiza la necesidad de suplementación durante el entrenamiento en el deporte del rugby: foco en el sistema inmunitario

Resumo O estudo analisou a imunidade oral após treino de rúgbi em atletas submetidos à dieta com alto teor de carboidratos (DATC). Em estudo randomizado, duplo-cego e placebo controlado, 20 atletas consumiram DATC por três dias antes do experimento. Os atletas receberam aleatoriamente bebida carboidratada (CHO) ou placebo (PLA) e participaram de duas sessões de treino de rúgbi, separados por sete dias. Coletas de saliva foram feitas antes (Pré-E), imediatamente após (Pós-E) e 1 h após (1 h Pós-E) o jogo-treino. Houve diferença significativa em taxa de secreção de IgA-s para PLA somente no tempo 1 h Pós-E. DATC, dias antes de treino de rúgbi, preserva função imunológica oral independente da suplementação de CHO durante treino.

Abstract The study analyzed the oral immunity after rugby training in athletes undergoing diet high in carbohydrates (DATC). In a randomized, double-blind, placebo-controlled, 20 athletes consumed DATC for three days before the experiment. The athletes were randomly carbohydrate drink (CHO) or placebo (PLA) and participated in two training sessions of rugby, separated by seven days. Saliva samples were taken before (Pre-E), immediately after (Post-E) and 1 h after (1 h post-E) training. Significant difference in rate of s-IgA secretion to PLA only at time 1 h post-E. DATC, days before training rugby, preserves immune function independent of oral CHO supplementation during training.

Resumen El estudio analizó la inmunidad oral después del entrenamiento de rugby en jugadores sometidos a una dieta elevada en hidratos de carbono (DEHC). En un estudio aleatorizado, a doble ciego, controlado con placebo, 20 jugadores consumieron una DEHC durante 3 días antes del experimento. Los jugadores recibieron aleatoriamente bebida de hidratos de carbono (CHO) o placebo (PLA), y participaron en dos sesiones de entrenamiento de rugby, separadas entre sí 7 días. Las muestras de saliva fueron antes (pre-E), inmediatamente después (post-E) y 1 hora después (1 h post-E). Hubo una diferencia significativa en la tasa de secreción de s-IgA a PLA sólo en 1 h post-E. La DEHC, días antes de la sesión de rugby, preserva la función inmunológica independientemente de la suplementación de CHO durante el entrenamiento.

Secondary hyperalgesia occurs regardless of unilateral or bilateral knee osteoarthritis involvement in individuals with mild or moderate level / A hiperalgesia secundária ocorre independentemente do envolvimento unilateral ou bilateral da osteoartrite de joelho em indivíduos com doença leve ou moderada

ABSTRACT Background: Secondary hyperalgesia in individuals with less severe levels of knee osteoarthritis remains unclear. The objective of this study was to measure the pressure pain threshold of individuals with mild or moderate knee osteoarthritis and compare with no osteoarthritis. Methods: Ten healthy controls and 30 individuals with mild or moderate knee osteoarthritis divided into two groups (unilateral and bilateral involvement) were included. Dermatomes in lumbar levels (L1, L2, L3, L4 and L5) and sacral level (S1 and S2), myotomes (vastus medialis, vastus lateralis, rectus femoris, adductor longus, tibialis anterior, peroneus longus, iliacus, quadratus lumborum, and popliteus muscles), and sclerotomes in lumbar levels (L1-L2, L2-L3, L3-L4, L4-L5 supraspinous ligaments), over the L5-S1 and S1-S2 sacral areas, pes anserinus bursae, and at the patellar tendon pressure pain threshold were assessed and compared between individuals with and without knee osteoarthritis. Results: Knee osteoarthritis groups (unilateral and bilateral) reported lower pressure pain threshold compared to the control group in most areas (dermatomes, myotomes, and sclerotomes). There were no between group differences in the supra-spinous ligaments and over the L5-S1 and S1-S2 sacral areas of the sclerotomes. No difference was seen between knee osteoarthritis. Conclusion: These findings suggest that individuals with mild to moderate knee osteoarthritis had primary and secondary hyperalgesia, independent of unilateral or bilateral involvement. These results suggest that the pain have to be an assertive focus in the clinical practice, independent of the level of severity or involvement of knee osteoarthritis.

RESUMO Introdução: A ocorrência de hiperalgesia secundária em indivíduos com níveis menos graves de osteoartrite de joelho ainda é incerta. O objetivo deste estudo foi medir o limiar de dor à pressão (LDP) de indivíduos com osteoartrite de joelho (OAJ) leve ou moderada e comparar com indivíduos sem osteoartrite. Métodos: Foram incluídos 10 controles saudáveis e 30 indivíduos com OAJ leve ou moderada, divididos em dois grupos (envolvimento unilateral e bilateral). Foi avaliado e comparado o LDP em dermátomos (L1, L2, L3, L4, L5, S1 e S2), miótomos (músculos vasto medial, vasto lateral, reto femoral, adutor longo, tibial anterior, fibular longo, ilíaco, quadrado lombar e poplíteo) e esclerótomos (ligamentos supraespinais L1-L2, L2-L3, L3-L4, L4-L5), sobre as áreas sacrais L5-S1 e S1-S2, bolsa anserina e tendão patelar entre os indivíduos com e sem OAJ. Resultados: Os grupos OAJ (unilateral e bilateral) relataram menor LDP em comparação com o grupo controle na maior parte das áreas (dermátomos, miótomos e esclerótomos). Não houve diferenças entre os grupos nos ligamentos supraespinais e ao longo das áreas sacrais L5-S1 e S1-S2 dos esclerótomos. Não foi observada qualquer diferença entre os indivíduos com OAJ. Conclusão: Esses achados sugerem que os indivíduos com OAJ leve a moderada tinham hiperalgesia primária e secundária, independentemente do acometimento unilateral ou bilateral. Esses resultados sugerem que a dor precisa ser um foco assertivo na prática clínica, independentemente do grau de gravidade ou envolvimento da OAJ.

Can pain influence the proprioception and the motor behavior in subjects with mild and moderate knee osteoarthritis?

BACKGROUND: Osteoarthritis (OA) is a chronic disease, usually characterized by pain, which is associated with reduced muscle strength, disability and progressive loss of function. However, the pain influence over proprioception and motor behaviour remains unclear. Thus, the purpose of the study was to identify the levels of pain, the proprioceptive acuity and the pattern of muscle recruitment during stair ascent and descent in elderly patients with mild and moderate osteoarthritis (OA) compared to healthy subjects. METHODS: The study participants included 11 healthy elderly subjects (7 women and 4 men) and 31 elderly patients with knee OA (19 women and 12 men). The functional capacity was assessed by the Western Ontario and McMaster Universities (WOMAC) osteoarthritis index; the pain was evaluated by Wong-Baker faces pain rating scale (WBS) and pressure pain threshold (PPT); the proprioceptive acuity was based on the joint position sense evaluated by electrogoniometer; and the electromyographic (EMG) activity of the major muscles of the lower limb were evaluated during a task of stair ascent and descent of 15 cm. For statistical analysis it was used Statistic for Windows software (StatSoft Inc., version 5.0). Data from the WOMAC index, WBS, the proprioceptive acuity and IEMG (for each muscle in each phase) were analyzed using the Mann-Whitney U test and data from PPT was used Kruskal-Wallis test. RESULTS: Higher scores were found in the WOMAC index and WBS whereas lower scores were seen in PPT in patients with knee OA compared to healthy subjects. In contrast, there were no significant differences in the proprioceptive acuity and EMG results of most muscles analyzed between the groups. CONCLUSION: The presence of pain does not influence the proprioception and the motor behavior of the thigh muscles during stair ascent and descent in subjects with mild and moderate knee OA.