Effects of a 10 vs. 20-Min Injury Prevention Program on Neuromuscular and Functional Performance in Adolescent Football Players

Effects of the FIFA 11+ program on performance, biomechanical measures, and physiological responses: A systematic review

BACKGROUND

The side effects of the FIFA 11+ program on performance have not been generally reviewed. The objective of this study was to synthesize the literature on the effects of the 11+ on players' performance.

METHODS

Five online databases (PubMed, Scopus, ScienceDirect, Springer, and Google Scholar) were searched (from April 2006 to March 2022) using predefined keywords and sub-keywords. The potential references were primarily recorded through Endnote and imported to Covidence. Out of the 123 references screened by 2 blinded researchers through the software, 59 full texts were assessed for eligibility, 33 of which were ultimately included. The quality of the studies and the risk of bias were then assessed. Study ID, title, place, aim, design, start/end dates, population description, study criteria, statistical analysis, and outcomes were extracted.

RESULTS

Studies were conducted on male and female players aged 10-32 years old. The quality of the studies was moderate to high, and except for unclear bias for blinding outcome assessment, the risk of bias for all domains was low. Long-term application of the 11+ improved most biomechanical measures and physiological responses except for lower extremity stability, ankle evertors time latency, ankle dorsiflexion, and proprioception. Conversely, the 11+ showed acute negative effects on physical performance compared to dynamic warm-ups and non-significant effects on technical abilities.

CONCLUSION

Mid-to-long-term implementation of the 11+ improved the majority of biomechanical and a couple of physical measures but showed no effects on technical skills. Precaution must be observed for using the 11+ before competitions, as it could acutely decrease physical/technical performance. Given the contradictory nature of the literature, further studies should evaluate the short-to-mid-term effects of the 11+. Further studies are required to address ankle responses to the 11+ intervention.

Ankle dorsiflexion range of motion and landing postures during a soccer-specific task

INTRODUCTION

Ankle dorsiflexion range of motion (DF-ROM) has been shown to be associated with poor landing posture. However, previously used tasks have been controlled, and it is unclear whether clinical measurements of the ankle DF-ROM, are associated with landing positions during sport-specific task. This study sought to determine the relationship between ankle DF-ROM and landing positions.

METHODS

Thirty male soccer players participated in this study. The ankle DF-ROM was measured by the weight bearing lunge test in degrees using a cell phone app (TiltMeter). Landing patterns were assessed during a soccer-specific task using landing error scoring system items using Kinovea software. Simple correlations were used to evaluate the relationships between ankle DF-ROM and landing error scores.

RESULTS

Significant correlations were found between ankle DF-ROM and landing errors (r = -0.450, P = 0.006). A decreased ankle DF-ROM was associated with greater landing errors in a soccer specific situation.

CONCLUSION

These results suggest that ankle DF-ROM may serve a useful clinical measure for identifying poor landing posture in the real-world environment. Therefore, assessment of ankle DF-ROM could be included in the screening process, which could help identify the cause of the faulty motion.

Quo Vadis Nordic Hamstring Exercise-Related Research?-A Scoping Review Revealing the Need for Improved Methodology and Reporting

The objective of this scoping review is to assess Nordic Hamstring Exercise quality (ANHEQ) of assessments and interventions according to the ANHEQ rating scales and to present practical recommendations for the expedient design and reporting of future studies. A total of 71 Nordic Hamstring Exercise (NHE) assessments and 83 NHE interventions were selected from the data sources PubMed, Scopus, and SPORTDiscus. Research studies which were presented in peer-reviewed academic journals and implemented the NHE during laboratory-based assessments or multi-week interventions met the eligibility criteria. NHE assessments analyzed force (51%), muscle activation (41%), knee angle kinematics (38%), and bilateral symmetry (37%). NHE interventions lasted 4-8 weeks (56%) and implied an exercise volume of two sessions per week (66%) with two sets per session (41%) and ≥8 repetitions per set (39%). The total ANHEQ scores of the included NHE assessments and interventions were 5.0 ± 2.0 and 2.0 ± 2.0 (median ± interquartile range), respectively. The largest deficits became apparent for consequences of impaired technique (87% 0-point-scores for assessments) and kneeling height (94% 0-point-scores for interventions). The 0-point-scores were generally higher for interventions compared to assessments for rigid fixation (87% vs. 34%), knee position (83% vs. 48%), kneeling height (94% vs. 63%), and separate familiarization (75% vs. 61%). The single ANHEQ criteria, which received the highest score most frequently, were rigid fixation (66% of assessments) and compliance (33% of interventions). The quality of NHE assessments and interventions was generally 'below average' or rather 'poor'. Both NHE assessments and interventions suffered from imprecise reporting or lacking information regarding NHE execution modalities and subsequent analyses. Based on the findings, this scoping review aggregates practical guidelines how to improve the design and reporting of future NHE-related research.

Chronic and Residual Effects of a Two-Week Foam Rolling Intervention on Ankle Flexibility and Dynamic Balance

Background

Foam rolling has been shown to acutely improve joint range of motion (ROM). However, limited knowledge exists on the chronic and residual effects. The primary purpose of this study was to examine the chronic and residual effects of a 2-week roller–massager intervention on ankle dorsiflexion ROM and dynamic balance.

Methods

Forty-two participants (24.3 ± 2.5 years, 33 males, 9 females) were randomly assigned to either roller-massage (RM) or control group (= no intervention). Ankle ROM was assessed with the weight-bearing lunge test (WBLT) and dynamic balance with the Y-Balance test for both limbs. The RM group was instructed to roll their calf muscles for three sets of 60 s per leg on 6 days a week over 2 weeks. Acute effects were measured during baseline testing for dorsiflexion ROM and dynamic balance immediately after foam rolling. Chronic and residual effects were measured 1 day and 7 days after the intervention period. Multivariate ANOVA was performed for post-hoc comparisons to determine acute, chronic, and residual effects.

Results

Significant acute and chronic foam rolling effects (p <0.05) were found for ankle dorsiflexion ROM. The chronic increase in ROM slightly decreased 7 days post-intervention but remained significantly above baseline (p < 0.05). Regarding dynamic balance, there were no acute but chronic (p < 0.05) and residual (p < 0.05) effects.

Conclusion

Using a roller–massager for a 2-week period chronically increases ROM and dynamic balance. These increases are still significant 7 days post-intervention emphasizing the sustainability of foam rolling effects.

Injury Profile among Elite Youth Male Football Players in a German Academy

Studies that report injuries in elite youth football players are scarce. So far, no such studies have been reported in Germany. The aim of this study is to descriptively and statistically report the incidence of injuries that resulted in time-loss ≥ 4 days in the TSG Hoffenheim football academy by 138 male players aged between 12 and 19 years during one season. A total of 109 injuries were sustained by 76 players: 6.9 injuries occurred per 1000 hours of matches (95% CI, 5.0-9.6) and 0.7 injuries per 1000 hours of training (95% CI, 0.5-0.9) with a ratio of 9.8. Some 66% of all injuries occurred during matches. Injuries involved the lower limb (81%), upper limb (9%), head & neck (5%) and trunk injuries (5%). 21 (19%) of all injuries were regarded as severe and resulted in time-loss > 28 days. U16-U19 teams sustained more injuries (74, 68%) than U12-U15 (35, 32%) (P= 0.032). The most frequent diagnosis was thigh strain (22%). Time-loss ranged from 4-339 days (SD: 40, Average: 23). Many injuries were a result of strain. Available injury prevention programs should be adhered to more strictly. Dedicated epidemiological studies are needed to optimize focused injury prevention programs.