Physical Demands of Tennis Across the Different Court Surfaces, Performance Levels and Sexes: A Systematic Review with Meta-analysis.

BACKGROUND: Tennis is a multidirectional high-intensity intermittent sport for male and female individuals played across multiple surfaces. Although several studies have attempted to characterise the physical demands of tennis, a meta-analysis is still lacking. OBJECTIVE: We aimed to describe and synthesise the physical demands of tennis across the different court surfaces, performance levels and sexes. METHODS: PubMed, Embase, CINAHL and SPORTDiscus were searched from inception to 19 April, 2022. A backward citation search was conducted for included articles using Scopus. The PECOS framework was used to formulate eligibility criteria. POPULATION: tennis players of regional, national or international playing levels (juniors and adults). EXPOSURE: singles match play. Comparison: sex (male/female), court surface (hard, clay, grass). OUTCOME: duration of play, on-court movement and stroke performance. STUDY DESIGN: cross-sectional, longitudinal. Pooled means or mean differences with 95% confidence intervals were calculated. A random-effects meta-analysis with robust variance estimation was performed. The measures of heterogeneity were Cochrane Q and 95% prediction intervals. Subgroup analysis was used for different court surfaces. RESULTS: The literature search generated 7736 references; 64 articles were included for qualitative and 42 for quantitative review. Mean [95% confidence interval] rally duration, strokes per rally and effective playing time on all surfaces were 5.5 s [4.9, 6.3], 4.1 [3.4, 5.0] and 18.6% [15.8, 21.7] for international male players and 6.4 s [5.4, 7.6], 3.9 [2.4, 6.2] and 20% [17.3, 23.3] for international female players. Mean running distances per point, set and match were 9.6 m [7.6, 12.2], 607 m [443, 832] and 2292 m [1767, 2973] (best-of-5) for international male players and 8.2 m [4.4, 15.2], 574 m [373, 883] and 1249 m [767, 2035] for international female players. Mean first- and second-serve speeds were 182 km·h-1 [178, 187] and 149 km·h-1 [135, 164] for international male players and 156 km·h-1 95% confidence interval [151, 161] and 134 km·h-1 [107, 168] for international female players. CONCLUSIONS: The findings from this study provide a comprehensive summary of the physical demands of tennis. These results may guide tennis-specific training programmes. We recommend more consistent measuring and reporting of data to enable future meta-analysts to pool meaningful data. CLINICAL TRIAL REGISTRATION: The protocol for this systematic review was registered a priori at the Open Science Framework (Registration DOI https://doi.org/10.17605/OSF.IO/MDWFY ).

Users' Perspectives, Opportunities, and Barriers of the Strengthen Your Ankle App for Evidence-Based Ankle Sprain Prevention: Mixed-Methods Process Evaluation for a Randomized Controlled Trial.

BACKGROUND: The "Strengthen Your Ankle" neuromuscular training program has been thoroughly studied over the past 8 years. This process evaluation is a part of a randomized controlled trial that examined both the short- and long-term effectiveness of this particular program. Although it was shown previously that the program, available both in a printed booklet and as a mobile app, is able to effectively reduce the number of recurrent ankle sprains, participants' compliance with the program is an ongoing challenge. OBJECTIVE: This process evaluation explored participants' opinions regarding both the methods of delivery, using RE-AIM (Reach Effectiveness Adoption Implementation Maintenance) Framework to identify barriers and challenges to program compliance. Although Reach, Effectiveness, and Adaptation were the focus of a previous study, this paper focuses on the implementation and maintenance phases. METHODS: Semistructured interviews and online questionnaires were analyzed using qualitative content analysis. Fisher exact, chi-square, and t tests assessed between-group differences in quantitative survey responses. Interviews were assessed by thematic analysis to identify key themes. RESULTS: While there were no significant differences in the perceived simplicity, usefulness, and liking of the exercise during the 8 weeks of the neuromuscular training program, semistructured interviews showed that 14 of 16 participants agreed that an app would be of additional benefits over a booklet. After the 12-month follow-up, when asked how they evaluated the overall use of the app or the booklet, the users of the app gave a mean score of 7.7 (SD 0.99) versus a mean score 7.1 (SD 1.23) for the users of the booklet. This difference in mean score was significant (P=.006). CONCLUSIONS: Although both the app and booklet showed a high user satisfaction, the users of the app were significantly more satisfied. Semistructured questionnaires allowed users to address issues they would like to improve in future updates. Including a possibility for feedback and postponement of exercises, an explanation of the use of specific exercises and possibly music were identified as features that might further improve the contentment of the program, probably leading to increased compliance. TRIAL REGISTRATION: Netherlands Trial Register NTR4027; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=4027 (Archived by Webcite at http://www.webcitation.org/70MTo9dMV).

Compliance with Sport Injury Prevention Interventions in Randomised Controlled Trials: A Systematic Review.

INTRODUCTION: Sport injury prevention studies vary in the way compliance with an intervention is defined, measured and adjusted for. OBJECTIVE: The objective of this systematic review was to assess the extent to which sport injury prevention randomised controlled trials (RCTs) have defined, measured and adjusted results for compliance with an injury prevention intervention. METHODS: An electronic search was performed in MEDLINE, PubMed, the Cochrane Center of Controlled Trials, CINAHL (Cumulative Index to Nursing and Allied Health Literature), PEDro (Physiotherapy Evidence Database) and SPORTDiscus. English RCTs, quasi-RCTs and cluster-RCTs were considered eligible. Trials that involved physically active individuals or examined the effects of an intervention aimed at the prevention of sport- or physical activity-related injuries were included. RESULTS: Of the total of 100 studies included, 71.6 % mentioned compliance or a related term, 68.8 % provided details on compliance measurement and 51.4 % provided compliance data. Only 19.3 % analysed the effect of compliance rates on study outcomes. While studies used heterogeneous methods, pooled effects could not be presented. CONCLUSIONS: Studies that account for compliance demonstrated that compliance significant affects study outcomes. The way compliance is dealt with in preventions studies is subject to a large degree of heterogeneity. Valid and reliable tools to measure and report compliance are needed and should be matched to a uniform definition of compliance.

The implementation effectiveness of the 'Strengthen your ankle' smartphone application for the prevention of ankle sprains: design of a randomized controlled trial.

BACKGROUND: Ankle sprains continue to pose a significant burden to the individual athlete, as well as to society as a whole. However, despite ankle sprains being the single most common sports injury and despite an active approach by various Dutch organisations in implementing preventive measures, large-scale community uptake of these preventive measures, and thus actual prevention of ankle sprains, is lagging well behind. In an attempt to bridge this implementation gap, the Dutch Consumer Safety Institute VeiligheidNL developed a freely available interactive App ('Strenghten your ankle' translated in Dutch as: 'Versterk je enkel; available for iOS and Android) that contains - next to general advice on bracing and taping - a proven cost-effective neuromuscular program. The 'Strengthen your ankle' App has not been evaluated against the 'regular' prevention approach in which the neuromuscular program is advocated through written material. The aim of the current project is to evaluate the implementation value of the 'Strengthen your ankle' App as compared to the usual practice of providing injured athletes with written materials. In addition, as a secondary outcome measure, the cost-effectiveness will be assessed against usual practice. METHODS/DESIGN: The proposed study will be a randomised controlled trial. After stratification for medical caregiver, athletes will be randomised to two study groups. One group will receive a standardized eight-week proprioceptive training program that has proven to be cost-effective to prevent recurrent ankle injuries, consisting of a balance board (machU/ MSG Europe BVBA), and a traditional instructional booklet. The other group will receive the same exercise program and balance board. However, for this group the instructional booklet is exchanged by the interactive 'Strengthen your ankle' App. DISCUSSION: This trial is the first randomized controlled trial to study the implementation effectiveness of an App for proprioceptive balance board training program in comparison to a traditional printed instruction booklet, with the recurrence of ankle sprains among athletes as study outcome. Results of this study could possibly lead to changes in practical guidelines on the treatment of ankle sprains and in the use of mobile applications for injury prevention. Results will become available in 2014. TRIAL REGISTRATION: The Netherlands National Trial Register NTR4027. The NTR is part of the WHO Primary Registries.