The effectiveness of neuromuscular warm-up strategies, that require no additional equipment, for preventing lower limb injuries during sports participation: a systematic review

PMCID: PMC3408383The electronic version of this article is the complete one and can be found online at: http://www.biomedcentral.com/1741-7015/10/75. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

Comprehensive warm-up programme to prevent injuries in young female footballers: cluster randomised controlled trial

Objective To examine the effect of a comprehensive warm-up programme designed to reduce the risk of injuries in female youth football

The Same Story or a Unique Novel? Within-Participant Principle Component Analysis of Training Load Measures in Professional Rugby Union Skills Training.

PURPOSE: The study aimed to identify which combination of external and internal training load (TL) metrics capture similar or unique information for individual professional players during skills training in rugby union using principal component analysis (PCA). METHOD: TL data were collected from twenty-one male professional rugby union players across a competitive season. This included PlayerLoad™, total distance (TD), and individualised high-speed distance (HSD; >61% maximal velocity; all external TL) obtained from a micro-technology device worn by each player (Optimeye X4, Catapult Innovations, Melbourne, Australia) and the session-rating of perceived exertion (sRPE; internal TL). PCA was conducted on each individual to extract the underlying combinations of the four TL measures that best describe the total information (variance) provided by the measures. TL measures with PC "loadings" (PCL) above 0.7 were deemed to possess well-defined relationships with the extracted PC. RESULTS: The findings show that from the four TL measures, the majority of an individual's TL information (1st PC: 55 to 70%) during skills training can be explained by either sRPE (PCL: 0.72 to 0.95), TD (PCL: 0.86 to 0.98) or PlayerLoad™ (PCL: 0.71 to 0.98). HSD was the only variable to relate to the 2nd PC (PCL: 0.72 to 1.00), which captured additional TL information (+19 to 28%). CONCLUSIONS: Findings suggest practitioners could quantify the TL of rugby union skills training with one of PlayerLoad™, TD, or sRPE plus HSD whilst limiting omitted information of the TL imposed during professional rugby union skills training

Visualising the complexity of the athlete monitoring cycle through principal component analysis

Purpose: The purpose of this invited commentary is to discuss the use of principal component analysis (PCA) as a dimension reduction and visualisation tool to assist in decision making and communication when analysing complex multivariate data sets associated with the training of athletes. Conclusions: Using PCA it is possible to transform a data matrix into a set of orthogonal composite variables called principal components (PC), with each PC being a linear weighted combination of the observed variables and with all PCs uncorrelated to each other. The benefit of transforming the data using PCA is that the first few PCs generally capture the majority of the information (i.e. variance) contained in the observed data, with the first PC accounting for the highest amount of variance and each subsequent PC capturing less of the total information. Consequently, through PCA it is possible to visualise complex data sets, containing multiple variables on simple 2D scatterplots without any great loss of information, thereby making it much easier to convey complex information to coaches. In the future, athlete monitoring companies should integrate PCA into their client packages to better support practitioners trying to overcome the challenges associated with multivariate data analysis and interpretation. In the interim, we present here an overview of PCA and associated R code to assist practitioners working within the field to integrate PCA into their athlete monitoring process

Scientific evidence is just the starting point: A generalizable process for developing sports injury prevention interventions

Background: The 2 most cited sports injury prevention research frameworks incorporate intervention development, yet little guidance is available in the sports science literature on how to undertake this complex process. This paper presents a generalizable process for developing implementable sports injury prevention interventions, including a case study applying the process to develop a lower limb injury prevention exercise training program (FootyFirst) for community Australian football. Methods: The intervention development process is underpinned by 2 complementary premises: (1) that evidence-based practice integrates the best available scientific evidence with practitioner expertise and end user values and (2) that research evidence alone is insufficient to develop implementable interventions. Results: The generalizable 6-step intervention development process involves (1) compiling research evidence, clinical experience, and knowledge of the implementation context; (2) consulting with experts; (3) engaging with end users; (4) testing the intervention; (5) using theory; and (6) obtaining feedback from early implementers. Following each step, intervention content and presentation should be revised to ensure that the final intervention includes evidence-informed content that is likely to be adopted, properly implemented, and sustained over time by the targeted intervention deliverers. For FootyFirst, this process involved establishing a multidisciplinary intervention development group, conducting 2 targeted literature reviews, undertaking an online expert consensus process, conducting focus groups with program end users, testing the program multiple times in different contexts, and obtaining feedback from early implementers of the program. Conclusion: This systematic yet pragmatic and iterative intervention development process is potentially applicable to any injury prevention topic across all sports settings and levels. It will guide researchers wishing to undertake intervention development

Association of Daily Workload, Wellness, and Injury and Illness During Tours in International Cricketers

Purpose: To examine the relationship between player internal workloads, daily wellness monitoring, and injury and illness in a group of elite adolescent cricketers during overseas competitions. Methods: A total of 39 male international adolescent cricketers (17.5 [0.8] y) took part in the study. Data were collected over 5 tours across a 3-y period (2014–2016). Measures of wellness were recorded and daily training loads were calculated using session rating of perceived exertion. The injury and illness status of each member of the squad was recorded daily. Acute and chronic workloads were calculated using 3-d and 14-d moving averages. Acute workloads, chronic workloads, and acute chronic workload ratios were independently modeled as fixed effects predictor variables. Results: In the subsequent week, a high 3-d workload was significantly associated with an increased risk of injury (relative risk = 2.51; CI = 1.70–3.70). Similarly, a high 14-d workload was also associated with an increased risk of injury (relative risk = 1.48; CI = 1.01–2.70). Individual differences in the load–injury relationship were also found. No clear relationship between the acute chronic workload ratios and injury risk was found, but high chronic workloads combined with high or low acute chronic workload ratios showed an increased probability of injury compared with moderate chronic workloads. There were also trends for sleep quality and cold symptoms worsening the week before an injury occurred. Conclusion: Although there is significant individual variation, short-term high workloads and change in wellness status appear to be associated with injury risk

Passion and Pacing in Endurance Performance

Endurance sports are booming, with sports passionates of varying skills and expertise battering city streets and back roads on their weekly or daily exercise rounds. The investments required for performing in endurance exercise are nevertheless considerable, and passion for their sport might explain the efforts endurance athletes are willing to make. Passion may be defined as a strong motivational force and as such might be related to the neurophysiological basis underlying the drive to exercise. A complex relationship between the brain and other systems is responsible for athletes' exercise behavior and thus performance in sports. We anticipate important consequences of athletes' short term choices, for example concerning risk taking actions, on long term outcomes, such as injuries, overtraining and burnout. We propose to consider athletes' type of passion, in combination with neurophysiological parameters, as an explanatory factor inunderstanding the apparent disparity in the regulation of exercise intensity during endurance sports. Previous research has demonstrated that athletes can be passionate toward their sport in either a harmonious or an obsessive way. Although both lead to considerable investments and therefore often to successful performances, obsessive passion may affect athlete well-being and performance on the long run, due to the corresponding inflexible exercise behavior. In this perspective we will thus examine the influence of passion in sport on athletes' short term and long term decision-making and exercise behavior, in particular related to the regulation of exercise intensity, and discuss the expected long term effects of both types of passion for sport

Effective But Not Adhered to:How Can We Improve Adherence to Evidence-Based Hamstring Injury Prevention in Amateur Football?

Objectives: To investigate adherence to a Nordic hamstring exercise (NHE) program in a real-world context of male amateur football, and the perceptions of end users (players) and intervention deliverers (coaches and medical staff) about adherence to this proven effective program. Design: Retrospective cohort study. Setting: Dutch amateur football. Participants: Two hundred sixty-four players, 23 coaches, and 29 medical staff from Dutch amateur football teams that participated in a national randomized controlled trial 2 years earlier. Independent Variables: Nordic hamstring exercise program. Main Outcome Measures: Nordic hamstring exercise program adherence during 2014 and 2015. Intervention or control group allocation during the trial, transfers, and personal perception about adherence to the program were also examined. Results: Of all players, 69% reported never, 16% sometimes, 6% frequently, 5% often, and 4% always performing exercises of the NHE program. Adherence to the NHE program was higher among players who had been in the NHE arm of the previous trial and among players who had not been transferred to another club compared with players who had been transferred. Key factors in stimulating players to adhere to the NHE program were knowledge of the NHE and personal motivation. Coaches and medical staff members also mentioned personal motivation and consensus with team staff as key factors to encourage NHE adherence. Conclusions: Among high-level male amateur football players, adherence to an evidence-based hamstring injury-prevention program was very low. It is essential to recognize factors that stimulate or limit adherence to injury-prevention programs for effective programs to actually lead to a reduction in hamstring injuries in a real-world context