Health and economic burden of running-related injuries in runners training for an event: A prospective cohort study

Definitions and surveillance methods of running-related injuries: A scoping review

Inconsistent and restricted definitions of injury have contributed to limitations in determining injury rates and identifying risk factors for running-related injuries (RRIs). The aim of this scoping review was to investigate the definitions and surveillance methods of RRIs. A systematic electronic search was performed using PubMed, Scopus, SPORTDiscuss, MEDLINE, and Web of Science databases. Included studies were published in English between January 1980 and June 2023 which investigated RRIs in adult running populations, providing a definition for a general RRI. Results were extracted and collated. 204 articles were included. Three primary criteria were used to define RRIs: physical description, effect on training and medical intervention, while three secondary criteria are also associated with definitions: cause/onset of injury, location, and social consequences. Further descriptors and sub-descriptors form these criteria. The use of Boolean operators resulted in nine variations in definitions. Inconsistency is evident among definitions of RRIs. Injury definitions seem to be important for two main reasons: firstly, determining accurate injury rates, and secondly, in research examining risk factors. For the latter, definitions seem to be very limited, only capturing severe injuries and failing to recognise the full development process of RRIs, precluding the identification of conclusive risk factors. A potential two-approach solution is the initial use of a broad definition acting as a gatekeeper for identifying any potential injury, and follow-up with an extensive surveillance tool to capture the specific consequences of the varying severity of RRIs.

Whipping or tearing? The biomechanics of Achilles tendinopathy in rearfoot strike runners

BACKGROUND

Two biomechanical mechanisms for the development of Achilles tendinopathy in runners have been proposed: A whipping mechanism characterized by prolonged and excessive rearfoot eversion, and a tearing mechanism characterized by high eccentric plantar flexor forces. The purpose of this pilot study was to determine if runners with and without a history of Achilles tendinopathy exhibited gait biomechanics consistent with either of these mechanisms.

METHODS

Seven male runners with previous or current Achilles tendinopathy and seven healthy male control runners were evaluated by three-dimensional gait analysis. Peak rearfoot eversion angle, rearfoot eversion excursion, duration of rearfoot eversion, and peak rearfoot inversion angle were compared between groups to evaluate the whipping mechanism of injury. Peak dorsiflexion angle, peak dorsiflexion velocity, and peak ankle power absorption were compared between groups to evaluate the tearing mechanism. Additionally, rearfoot eversion angle and sagittal plane ankle power waveforms were compared between groups using statistical parametric mapping.

FINDINGS

There were no differences in any rearfoot eversion, inversion, or dorsiflexion variables or waveforms during running in the Achilles tendinopathy group compared to controls.

INTERPRETATION

Rearfoot strike runners with Achilles tendinopathy do not exhibit running biomechanics consistent with either the whipping or tearing mechanisms of injury.

Estimating the cost of sports injuries: A scoping review

OBJECTIVES

Provide an overview of the methods used to estimate the cost of sports-related injury published to date, and to highlight considerations and opportunities for future research.

DESIGN

Scoping review.

METHODS

Scopus, MEDLINE and CINHAL were searched from 1st January 2000 to 1st January 2023. Studies were screened by two independent reviewers and were eligible if they reported on a cost analysis or cost estimation of sports related injury.

RESULTS

Thirty-one studies fulfilled the inclusion criteria. Twenty-seven studies (87 %) were published since 2014. The type of costs included direct healthcare costs (12 studies), indirect costs (10 studies) and a combination of both (9 studies). Twenty-one studies (68 %) used a bottom-up costing approach to measure costs of sports injury and estimated direct costs from the service rates or fee schedules of health systems, hospital, insurance companies or national insurance boards. A top-down approach was used in seven studies (23 %) to estimate the indirect salary cost of time-loss injuries using data from publicly available resources. Ten studies were from the cost perspective of a sporting organisation (32 %). There was a lack of explicit reporting of the costing method used and the perspective of those bearing the costs.

CONCLUSIONS

Estimating the cost of sports injuries is an emerging area of research, with publications increasing in recent years. However, there remains a lack of methodological guidance to inform or appraise these studies. The expansion of established cost of illness checklists with sport injury explanations to guide future cost of sports injury studies is recommended.

Risk factors for running-related injuries: An umbrella systematic review

PURPOSE

This umbrella systematic review (SR) of SRs and meta-analysis seeks to comprehensively synthesize existing literature to identify and consolidate the diverse range of risk factors contributing to running-related injuries (RRIs).

METHODS

Systematic searches were conducted on June 28, 2023, across Web of Science, SPORTDiscus, Scopus, PubMed, and Cochrane Library. We included SRs, whether accompanied by meta-analyses or not, that focused on investigating risk factors for RRIs within observational studies. The methodological quality of the SRs was evaluated using the Assessing the Methodological Quality of Systematic Reviews II. To assess the extent of overlap across reviews, the corrected covered area metric was calculated.

RESULTS

From 1509 records retrieved, 13 SRs were included. The degree of overlap between SRs was low (4%), and quality varied from critically low (n = 8) to low (n = 5). Two hundred seven outcomes assessed in 148 primary studies were identified as being associated with the occurrence of RRIs. The effect sizes of the associations for which risk measures were reported (n = 131) were classified as large (n = 30, 23%), medium (n = 38, 29%), small (n = 48, 37%) or no effect (n = 15, 11%). Running/training characteristics, health and lifestyle factors, along with morphological and biomechanical aspects, exhibit large effect sizes in increasing the risk for RRIs.

CONCLUSION

Drawing from the outcomes of the low-quality SRs and associations with large effect sizes, our findings indicate that running/training characteristics and health and lifestyle factors, as well as morphological and biomechanical aspects, are all implicated in elevating the risk of RRIs, emphasizing the multifactorial basis of injury incidence in running. Given the low quality and heterogeneity of SR, individual findings warrant cautious interpretation.

Comparing Self-Reported Running Distance and Pace With a Commercial Fitness Watch Data: Reliability Study

BACKGROUND

There is substantial evidence exploring the reliability of running distance self-reporting and GPS wearable technology, but there are currently no studies investigating the reliability of participant self-reporting in comparison to GPS wearable technology. There is also a critical sports science and medical research gap due to a paucity of reliability studies assessing self-reported running pace.

OBJECTIVE

The purpose of this study was to assess the reliability of weekly self-reported running distance and pace compared to a commercial GPS fitness watch, stratified by sex and age. These data will give clinicians and sports researchers insights into the reliability of runners' self-reported pace, which may improve training designs and rehabilitation prescriptions.

METHODS

A prospective study of recreational runners was performed. Weekly running distance and average running pace were captured through self-report and a fitness watch. Baseline characteristics collected included age and sex. Intraclass correlational coefficients were calculated for weekly running distance and running pace for self-report and watch data. Bland-Altman plots assessed any systemic measurement error. Analyses were then stratified by sex and age.

RESULTS

Younger runners reported improved weekly distance reliability (median 0.93, IQR 0.92-0.94). All ages demonstrated similar running pace reliability. Results exhibited no discernable systematic bias.

CONCLUSIONS

Weekly self-report demonstrated good reliability for running distance and moderate reliability for running pace in comparison to the watch data. Similar reliability was observed for male and female participants. Younger runners demonstrated improved running distance reliability, but all age groups exhibited similar pace reliability. Running pace potentially should be monitored through technological means to increase precision.

A novel approach for sports injury risk prediction: based on time-series image encoding and deep learning

The rapid development of big data technology and artificial intelligence has provided a new perspective on sports injury prevention. Although data-driven algorithms have achieved some valuable results in the field of sports injury risk assessment, the lack of sufficient generalization of models and the inability to automate feature extraction have made it challenging to deploy research results in the real world. Therefore, this study attempts to build an injury risk prediction model using a combination of time-series image encoding and deep learning algorithms to address this issue better. This study used the time-series image encoding approach for feature construction to represent relationships between values at different moments, including Gramian Angular Summation Field (GASF), Gramian Angular Difference Field (GADF), Markov Transition Field (MTF), and Recurrence Plot (RP). Deep Convolutional Auto-Encoder (DCAE) learned the image-encoded data for representation to obtain features with good discrimination, and the classifier was performed using Deep Neural Network (DNN). The results from five repeated experiments show that the GASF-DCAE-DNN model is overall better in the training (AUC: 0.985 ± 0.001, Gmean: 0.930 ± 0.007, Sensitivity: 0.997 ± 0.003, Specificity: 0.868 ± 0.013) and test sets (AUC: 0.891 ± 0.026, Gmean: 0.830 ± 0.027, Sensitivity: 0.816 ± 0.039, Specificity: 0.845 ± 0.022), with good discriminative power, robustness, and generalization ability. Compared with the best model reported in the literature, the AUC, Gmean, Sensitivity, and Specificity of the GASF-DCAE-DNN model were higher by 23.9%, 27.5%, 39.7%, and 16.2%, respectively, which confirmed the validity and practicability of the model in injury risk prediction. In addition, differences in injury risk patterns between the training and test sets were identified through shapley additivity interpretation. It was also found that the training volume was an essential factor that affected injury risk prediction. The model proposed in this study provides a powerful injury risk prediction tool for future sports injury prevention practice.

The Effects of Exercise-Based Injury Prevention Programmes on Injury Risk in Adult Recreational Athletes: A Systematic Review and Meta-Analysis

BACKGROUND

Injuries are common in adult recreational athletes. Exercise-based injury prevention programmes offer the potential to reduce the risk of injury and have been a popular research topic. Yet, syntheses and meta-analyses on the effects of exercise-based injury prevention programmes for adult recreational athletes are lacking.

OBJECTIVES

We aimed to synthesise and quantify the pooled intervention effects of exercise-based injury prevention programmes delivered to adults who participate in recreation sports.

METHODS

Studies were eligible for inclusion if they included adult recreational athletes (aged > 16 years), an exercise-based intervention and used a randomised controlled trial design. Exclusion criteria were studies without a control group, studies using a non-randomised design and studies including participants who were undertaking activity mandatory for their occupation. Eleven literature databases were searched from earliest record, up to 9 June, 2022. The Physiotherapy Evidence Database (PEDro) scale was used to assess the risk of bias in all included studies. Reported risk statistics were synthesised in a random-effects meta-analysis to quantify pooled treatment effects and associated 95% confidence intervals and prediction intervals.

RESULTS

Sixteen studies met the criteria. Risk statistics were reported as risk ratios [RRs] (n = 12) or hazard ratios [HRs] (n = 4). Pooled estimates of RRs and HRs were 0.94 (95% confidence interval 0.80-1.09) and 0.65 (95% confidence interval 0.39-1.08), respectively. Prediction intervals were 0.80-1.09 and 0.16-2.70 for RR and HR, respectively. Heterogeneity was very low for RR studies, but high for HR studies (tau = 0.29, I2 = 81%). There was evidence of small study effects for RR studies, evidenced by funnel plot asymmetry and Egger's test for small study bias: - 0.99 (CI - 2.08 to 0.10, p = 0.07).

CONCLUSIONS

Pooled point estimates were suggestive of a reduced risk of injury in intervention groups. Nevertheless, these risk estimates were insufficiently precise, too heterogeneous and potentially compromised by small study effects to arrive at any robust conclusion. More large-scale studies are required to clarify whether exercise-based injury prevention programmes are effective in adult recreational athletes.

CLINICAL TRIAL REGISTRATION

The protocol for this review was prospectively registered in the PROSPERO database (CRD42021232697).

Running-Related Overuse Injuries and Their Relationship with Run and Resistance Training Characteristics in Adult Recreational Runners: A Cross-Sectional Study

This study aimed to characterize running-related injuries (RRIs), explore their relationship with run and resistance training (RT) parameters, and identify perceived prevention measures among adult recreational runners. An anonymous online survey was designed and distributed via social media and email. Data were analyzed with chi-square, t-test, or analysis of variance (ANOVA), with significance accepted at p ≤ 0.05. Data from 616 participants (76.8% female, age: 42.3 ± 10.5 y) were analyzed. Most runners (84.4%) had an injury history, with 44.6% experiencing one in the past year. The most common RRI sites included the foot/ankle (30.9%) and knee (22.2%). RRI prevalence was higher in those running >19 miles weekly (48.4%, p = 0.05), but there were no differences based on RT participation status. Among those using RT, relatively more RRIs were observed in runners who trained the hip musculature (50.3%, p = 0.005) and did not include the upper body (61.6%, p < 0.001). A disproportionately high RRI prevalence was found for several of the other risk-reduction strategies. RRIs remain a substantial problem, particularly around the ankle/foot and knee. Higher run volume and performance motives were positively associated with RRIs. Most runners incorporated RRI risk-reduction techniques, with over half using RT. The current study did not determine whether preventative strategies were implemented before or after injury; therefore, prospective studies controlling for previous injuries are required to evaluate the effectiveness of RT in preventing future RRIs.

Aetiological Factors of Running-Related Injuries: A 12 Month Prospective "Running Injury Surveillance Centre" (RISC) Study

BACKGROUND

Running-related injuries (RRIs) are a prevalent issue for runners, with several factors proposed to be causative. The majority of studies to date are limited by retrospective study design, small sample sizes and seem to focus on individual risk factors in isolation. This study aims to investigate the multifactorial contribution of risk factors to prospective RRIs.

METHODS

Recreational runners (n = 258) participated in the study, where injury history and training practices, impact acceleration, and running kinematics were assessed at a baseline testing session. Prospective injuries were tracked for one year. Univariate and multivariate Cox regression was performed in the analysis.

RESULTS

A total of 51% of runners sustained a prospective injury, with the calf most commonly affected. Univariate analysis found previous history of injury < 1 year ago, training for a marathon, frequent changing of shoes (every 0-3 months), and running technique (non-rearfoot strike pattern, less knee valgus, greater knee rotation) to be significantly associated with injury. The multivariate analysis revealed previous injury, training for a marathon, less knee valgus, and greater thorax drop to the contralateral side to be risk factors for injury.

CONCLUSION

This study found several factors to be potentially causative of injury. With the omission of previous injury history, the risk factors (footwear, marathon training and running kinematics) identified in this study may be easily modifiable, and therefore could inform injury prevention strategies. This is the first study to find foot strike pattern and trunk kinematics to relate to prospective injury.

Do Highly Trained Mountain Runners Differ from Recreational Active Non-Runners on Range of Motion and Strength in the Hip and Ankle as Well as Postural Control?

The rules governing mountain running force athletes to implement into their training programmes uphill and downhill running on unstable surfaces, which are demanding for hip and ankle as well as for the postural control system. The aim of the present cross-sectional study was to compare highly trained mountain runners (MR) and recreational active non-runners (NR) on range of motion (ROM) and strength in the hip and ankle, as well as dynamic postural control. Thirty MR and thirty-two NR were included in the study. ROM was assessed using a digital inclinometer. Strength was measured using a hand-held dynamometer. Postural control was evaluated using the lower quarter Y-balance test (YBT-LQ). The results showed that MR, in relation to NR, had statistically significant smaller hip external rotation ROM (p = 0.007), lower hip external rotator (p = 0.006) and extensor (p = 0.023) strength and greater normalised anterior reach in the YBT-LQ (p = 0.028). Mountain running training may reduce hip external rotation ROM as well as hip external rotator and extensor strength. Moreover, such training may improve postural control. MR should implement exercises targeted at developing hip ROM and strength. Furthermore, it seems that mountain running training may be a good way to improve postural control.

Training patterns associated with injury in New York City Marathon runners

OBJECTIVE

Training patterns are commonly implicated in running injuries. The purpose of this study was to measure the incidence of injury and illness among marathon runners and the association of injuries with training patterns and workload.

METHODS

Runners registered for the New York City Marathon were eligible to enrol and prospectively monitored during the 16 weeks before the marathon, divided into 4-week 'training quarters' (TQ) numbered TQ1-TQ4. Training runs were tracked using Strava, a web and mobile platform for tracking exercise. Runners were surveyed at the end of each TQ on injury and illness, and to verify all training runs were recorded. Acute:chronic workload ratio (ACWR) was calculated by dividing the running distance in the past 7 days by the running distance in the past 28 days and analysed using ratio thresholds of 1.3 and 1.5.

RESULTS

A total of 735 runners participated, mean age 41.0 (SD 10.7) and 46.0% female. Runners tracked 49 195 training runs. The incidence of injury during training was 40.0% (294/735), and the incidence of injury during or immediately after the marathon was 16.0% (112/699). The incidence of illness during training was 27.2% (200/735). Those reporting an initial injury during TQ3 averaged less distance/week during TQ2 compared with uninjured runners, 27.7 vs 31.9 miles/week (p=0.018). Runners reporting an initial injury during TQ1 had more days when the ACWR during TQ1 was ≥1.5 compared with uninjured runners (injured IQR (0-3) days vs uninjured (0-1) days, p=0.009). Multivariable logistic regression for training injuries found an association with the number of days when the ACWR was ≥1.5 (OR 1.06, 95% CI (1.02 to 1.10), p=0.002).

CONCLUSION

Increases in training volume ≥1.5 ACWR were associated with more injuries among runners training for a marathon. These findings can inform training recommendations and injury prevention programmes for distance runners.

Effects of compression running pants and treadmill running stages on knee proprioception and fatigue-related physiological responses in half-marathon runners

Background: Knee injury is common in half-marathon runners, however, the effect of compression running pants on fatigue and knee proprioception remains unclear. Objectives: The study aims to investigate whether wearing compression running pants (CRP) and treadmill running stages affect knee proprioception and fatigue-related physiological responses during half-marathon running. Methods: Eighteen half-marathon runners completed two self-paced 21 km treadmill running trials, once wearing CRP and once wearing loose running shorts (LRS). For each 21 km run, RPE, heart rate, blood lactic acid, and knee flexion proprioception were assessed before starting, and after each 7 km stage. Results: Data analysis revealed no difference between CRP and LRS conditions in heart rate, RPE, or blood lactic acid. Repeated measures ANOVA showed a significant garment condition main effect whereby wearing CRP was associated with higher knee proprioceptive acuity (p = 0.006). Polynomial trend analysis showed a significant linear downwards trend in proprioceptive acuity across the four measurement occasions (p = 0.048). Stage analysis showed that wearing CRP was associated with better knee proprioception at running distances of 14 km (p = 0.007, 95%CI = -0.054, -0.010) and 21 km (p = 0.016, 95%CI = -0.051, -0.006). Conclusion: Compression running pants provide an overall positive effect on knee proprioception, particularly after 14 km and 21km, which may reduce the probability of knee injury. CRP had no significant effect on physiological measures in half-marathon running.

Validity and Reliability of Inertial Measurement Units on Lower Extremity Kinematics During Running: A Systematic Review and Meta-Analysis

Background

Inertial measurement units (IMUs) are useful in monitoring running and alerting running-related injuries in various sports settings. However, the quantitative summaries of the validity and reliability of the measurements from IMUs during running are still lacking. The purpose of this review was to investigate the concurrent validity and test–retest reliability of IMUs for measuring gait spatiotemporal outcomes and lower extremity kinematics of health adults during running.

Methods

PubMed, CINAHL, Embase, Scopus and Web of Science electronic databases were searched from inception until September 2021. The inclusion criteria were as follows: (1) evaluated the validity or reliability of measurements from IMUs, (2) measured specific kinematic outcomes, (3) compared measurements using IMUs with those obtained using reference systems, (4) collected data during running, (5) assessed human beings and (6) were published in English. Eligible articles were reviewed using a modified quality assessment. A meta-analysis was performed to assess the pooled correlation coefficients of validity and reliability.

Results

Twenty-five articles were included in the systematic review, and data from 12 were pooled for meta-analysis. The methodological quality of studies ranged from low to moderate. Concurrent validity is excellent for stride length (intraclass correlation coefficient (ICC) (95% confidence interval (CI)) = 0.937 (0.859, 0.972), p < 0.001), step frequency (ICC (95% CI) = 0.926 (0.896, 0.948), r (95% CI) = 0.989 (0.957, 0.997), p  < 0.001) and ankle angle in the sagittal plane (r (95% CI) = 0.939 (0.544, 0.993), p = 0.002), moderate to excellent for stance time (ICC (95% CI) = 0.664 (0.354, 0.845), r (95% CI) = 0.811 (0.701, 0.881), p < 0.001) and good for running speed (ICC (95% CI) = 0.848 (0.523, 0.958), p = 0.0003). The summary Fisher's Z value of flight time was not statistically significant (p = 0.13). Similarly, the stance time showed excellent test–retest reliability (ICC (95% CI) = 0.954 (0.903, 0.978), p < 0.001) and step frequency showed good test–retest reliability (ICC (95% CI) = 0.896 (0.837, 0.933), p < 0.001).

Conclusions

Findings in the current review support IMUs measurement of running gait spatiotemporal parameters, but IMUs measurement of running kinematics on lower extremity joints needs to be reported with caution in healthy adults.

Trial Registration: PROSPERO Registration Number: CRD42021279395.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40798-022-00477-0.

Machine-learned-based prediction of lower extremity overuse injuries using pressure plates

Although running has many benefits for both the physical and mental health, it also involves the risk of injuries which results in negative physical, psychological and economical consequences. Those injuries are often linked to specific running biomechanical parameters such as the pressure pattern of the foot while running, and they could potentially be indicative for future injuries. Previous studies focus solely on some specific type of running injury and are often only applicable to a gender or running-experience specific population. The purpose of this study is, for both male and female, first-year students, (i) to predict the development of a lower extremity overuse injury in the next 6 months based on foot pressure measurements from a pressure plate and (ii) to identify the predictive loading features. For the first objective, we developed a machine learning pipeline that analyzes foot pressure measurements and predicts whether a lower extremity overuse injury is likely to occur with an AUC of 0.639 and a Brier score of 0.201. For the second objective, we found that the higher pressures exerted on the forefoot are the most predictive for lower extremity overuse injuries and that foot areas from both the lateral and the medial side are needed. Furthermore, there are two kinds of predictive features: the angle of the FFT coefficients and the coefficients of the autoregressive AR process. However, these features are not interpretable in terms of the running biomechanics, limiting its practical use for injury prevention.

Tibial bone forces can be monitored using shoe-worn wearable sensors during running

Tibial bone stress injury is a common overuse injury experienced by runners, which results from repetitive tissue forces. Wearable sensor systems (wearables) that monitor tibial forces could help understand and reduce injury incidence. However, there are currently no validated wearables that monitor tibial bone forces. Previous work using simulated wearables demonstrated accurate tibial force estimates by combining a shoe-worn inertial measurement unit (IMU) and pressure insole with a trained algorithm. This study aimed assessed how accurately tibial bone forces could be estimated with existing wearables. Nine recreational runners ran at a series of different speeds and slopes, and with various stride patterns. Shoe-worn IMU and insole data were input into a trained algorithm to estimate peak tibial force. We found an average error of 5.7% in peak tibial force estimates compared with lab-based estimates calculated using motion capture and a force instrumented treadmill. Insole calibration procedures were essential to achieving accurate tibial force estimates. We concluded that a shoe-worn, multi-sensor system is a promising approach to monitoring tibial bone forces in running. This study adds to the literature demonstrating the potential of wearables to monitor musculoskeletal forces, which could positively impact injury prevention, and scientific understanding.

Factors associated with injuries in first-time marathon runners from the New York City marathon

OBJECTIVES

To determine how baseline characteristics of first-time marathon runners and training patterns are associated with risk of injuries during training and the race.

METHODS

First-time adult marathon runners who were registered for the 2017 New York City Marathon were monitored starting 12 weeks prior to the race. Baseline data collection included demographics and running experience. Running frequency, distance, and injury occurrence were self-reported using online surveys every 2 weeks.

RESULTS

A total of 720 runners participated of which 675 completed the study. There were 64/675 (9.5%) who had major injuries during training or the race that preventing starting or finishing the race. An additional 332 (49.2%) had minor injuries interfering with training and/or affecting race performance. Injury incidence was not significantly different based on age or sex. Runners who completed a half marathon prior to the study were less likely to report getting injured [multivariable odds ratio (OR) 0.40, (0.22, 0.76), p= 0.005]. Runners who averaged <4 training runs per week during the study were less likely to report getting injured compared to those who averaged ≥4 per week [relative risk 1.36, (1.13-1.63), p= 0.001]. Longest training run distance during the study was inversely associated with race-day injury incidence [OR 0.87 (0.81, 0.94), p< 0.001].

CONCLUSION

Injuries are common among first-time marathon runners. We found that risk of injury during training was associated with lack of half marathon experience and averaging ≥4 training runs per week. Longer training runs were associated with a lower incidence of race-day injuries. These results can inform the development of targeted injury-prevention interventions.

Biomechanical and Musculoskeletal Measurements as Risk Factors for Running-Related Injury in Non-elite Runners: A Systematic Review and Meta-analysis of Prospective Studies

BACKGROUND

Running-related injury (RRI) is highly prevalent among recreational runners and is a key barrier to participation. Atypical lower limb alignment and mechanical function have been proposed to play a role in development of lower extremity injury. The purpose of this study was to investigate relationships between incidence of running-related injury (RRI) in non-elite runners with biomechanical and musculoskeletal variables.

METHODS

A systematic review and meta-analysis of prospective studies. Published research indexed in MEDLINE, EMBASE, CINAHL, SPORTDiscus, AMED, and The Cochrane library until 13th January 2021, grey literature, and reference lists of included studies were screened to identify prospective studies of non-elite adult runners that measured a relationship between biomechanical or musculoskeletal measures and incidence of RRI.

RESULTS

Thirty studies (3404 runners), testing over 100 discrete biomechanical and musculoskeletal risk factors for RRI, were included. Nineteen studies were pooled in twenty-five separate meta-analyses. Meta-analysis of four studies detected significantly less knee extension strength among runners who developed a RRI (SMD - 0.19, 95% CI - 0.36 to - 0.02, p = 0.03), though this may not be clinically important. A meta-analysis of two studies detected significantly lower hip adduction velocity among runners who developed a RRI (MD - 12.80, 95% CI - 25.22 to - 0.38, p = 0.04). Remaining meta-analyses found no significant relationship between biomechanical or musculoskeletal variables and RRI.

CONCLUSION

This systematic review and meta-analysis found the currently available literature does not generally support biomechanical or musculoskeletal measures as risk factors for RRI in non-elite runners. While meta-analysis findings for knee extension strength and hip adduction velocity as risk factors for RRI were statistically significant, the associated trivial to small effects sizes suggest these findings should be treated with caution. Until further evidence emerges, recommendations for injury prevention in non-elite runners cannot be made based on biomechanical and musculoskeletal measurements alone.

Using an external focus of attention for gait retraining in runners: A case report

INTRODUCTION

Many gait retraining studies use cues that promote internal focus of attention. However, the motor control literature clearly shows the beneficial effects of using cues that promote an external focus of attention (EFOA) when teaching new movements. This case report seeks to illustrate the outcomes of using an EFOA for running gait retraining. It also examines whether retrained mechanics transfer across different running speeds.

CASE DESCRIPTIONS

A 22-year-old female competitive runner with a history of tibial stress injuries was the participant.

PATIENT MANAGEMENT

Baseline assessments of flexibility, strength, and running biomechanics were performed after which an eight-session gait retraining protocol was implemented. Visual (mirror) and verbal feedback (EFOA) cues were provided during the retraining protocol. Outcomes showed improved hip, knee, and ankle kinematics, reduced ground reaction forces, and earlier onset and longer durations of muscle activity following retraining. These improvements transferred across running speeds.

DISCUSSION AND CONCLUSION

In this participant, EFOA cues were effective for the gait retraining protocol and the benefits were transferable across running speeds. Clinicians should consider how EFOA cues may be incorporated to improve gait retraining outcomes.

Gait Retraining With Visual Biofeedback Reduces Rearfoot Pressure and Foot Pronation in Recreational Runners

CONTEXT

Running is a popular sport globally. Previous studies have used a gait retraining program to successfully lower impact loading, which has been associated with lower injury rates in recreational runners. However, there is an absence of studies on the effect of this training program on the plantar pressure distribution pattern during running.

OBJECTIVE

To investigate the short-term effect of a gait retraining strategy that uses visual biofeedback on the plantar pressure distribution pattern and foot posture in recreational runners.

DESIGN

Randomized controlled trial.

SETTING

Biomechanics laboratory.

PARTICIPANTS

Twenty-four recreational runners were evaluated (n = 12 gait retraining group and n = 12 control group).

INTERVENTION

Those in the gait retraining group underwent a 2-week program (4 sessions/wk, 30 min/session, and 8 sessions). The participants in the control group were also invited to the laboratory (8 times in 2 wk), but no feedback on their running biomechanics was provided.

MAIN OUTCOME MEASURES

The primary outcome measures were plantar pressure distribution and plantar arch index using a pressure platform. The secondary outcome measure was the foot posture index.

RESULTS

The gait retraining program with visual biofeedback was effective in reducing medial and lateral rearfoot plantar pressure after intervention and when compared with the control group. In the static condition, the pressure peak and maximum force on the forefoot and midfoot were reduced, and arch index was increased after intervention. After static training intervention, the foot posture index showed a decrease in the foot pronation.

CONCLUSIONS

A 2-week gait retraining program with visual biofeedback was effective in lowering rearfoot plantar pressure, favoring better support of the arch index in recreational runners. In addition, static training was effective in reducing foot pronation. Most importantly, these observations will help healthcare professionals understand the importance of a gait retraining program with visual biofeedback to improve plantar loading and pronation during rehabilitation.

Use of monitoring technology and injury incidence among recreational runners: a cross-sectional study

Background

Monitoring technology is increasingly accessible to recreational runners. Our aim was to examine patterns of technology use in recreational runners, and its potential association with injury.

Methods

We conducted a cross-sectional questionnaire study in a sample of adult runners. Recruitment took place at three different 5 km parkrun event across Northern Ireland. Demographics, technology use, running behaviour and running-related injury (RRI) history were examined. Regression analyses were performed to determine relationships between variables.

Results

Responses were obtained from 192 of 483 eligible finishers (39.8% response rate). Average age was 45.9 years (SD 10.3), with males (47.1 years SD 9.7) slightly older than females (44.8 years SD 10.8). On average, participants ran 3.0 days per week (SD 1.3), with an average weekly distance of 22.6 km (SD 19.7). Males typically ran further (MD 6.2 km/week; 95% CI 0.4 to 12.0) than females. Monitoring technology was used by 87.4% (153/175); with GPS watches the most common device (87.6% (134/153)). Runners using monitoring technology ran further (MD 14.4 km/week; 95% CI 10.3 to 18.5) and more frequently (MD 1.3 days/week; 95% CI 0.7 to 1.9) than those who did not use monitoring technology. There was no significant difference in average age between runners who used monitoring technology and those who did not (MD 4.0 years; 95% CI −0.7 to 8.7). RRI was reported by 40.6% (71/175) of participants in the previous 12 months. In a univariate analysis, none of the selected predictors (age, number of days run per week, distance run per week, or usage of technology to modify training pattern) (p > 0.1) were associated with RRI.

Conclusions

This study found a high prevalence of monitoring technology usage among recreational runners. While the incidence of RRI remains high, it is not associated with the usage of monitoring technology. Further prospective research should examine if monitoring technology can reduce RRI incidence among recreational runners in future.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13102-021-00347-4.

The socio-economic impact of running-related injuries: A large prospective cohort study

Objectives

To evaluate the impact of running‐related injuries (RRIs) on activities of daily living (ADL), work, healthcare utilization, and estimated costs.

Design

Prospective cohort study with data from a randomized controlled trial.

Methods

Adult recreational runners who registered for a running event (distances 5 to 42 km) were included in this study. Minimum follow‐up duration was 3 months (preparation, event participation, and post‐race period). Injuries were registered using a standardized definition. Primary outcome measure was a standardized 5‐item survey on limitations in ADL. The survey data were categorized to the number of injured runners with complete/moderate/no limitations. This outcome was expressed as the percentage of injured runners with any limitation (complete or moderate limitations amalgamated). Secondary outcomes were work absenteeism, the number of healthcare visits per injured runner, and estimated direct medical and indirect costs per participant and per RRI.

Results

1929 runners (mean [SD] age 41 [12] years, 53% men) were included in this study and 883 runners (46%) sustained a RRI during the course of the study. Injured runners reported the highest limitations (% with any limitation) of RRIs during the first week of injury on sports and leisure activities (70%) and transportation activities (23%). 39% of the injured runners visited a healthcare professional. Work absenteeism due to the RRI was reported in 5% of the injured runners. The total mean estimated costs were €74 per RRI and €35 per participant.

Conclusions

Injured runners are mainly limited in their transportation activities and during sports and leisure. While the estimated costs of RRIs are not high when expressed per participant, the absolute costs may be substantial due to the popularity of running.

RunIn3: the development process of a running-related injury prevention programme

BACKGROUND

Running is an important type of exercise to keep people physically active. However, running also carries a risk of developing running-related injuries (RRI). Therefore, effective and evidence-based RRI prevention programmes are desirable, but are scarce in practice. An approach to face this problem might be the application of methods to develop RRI prevention programmes based on theories of behaviour change.

OBJECTIVE

The purpose of the study was to develop an RRI prevention programme based on perspectives of behavioural and social science theories, as well as taking a framework development approach.

METHODS

This was a qualitative study using the Intervention Mapping (IM) framework held between February and March 2018 in São Paulo, Brazil. The participants were involved in running practice. The data collection was conducted during focus group meetings. The data analysis was based on semantic thematic approach using a content analysis orientation based on inductive reasoning.

RESULTS

The target population of the RRI prevention programme identified was 'adult recreational runners'. The objectives of the RRI prevention programme were established in two broad actions: (1) to provide feedback on individual training characteristics and RRI risk; and (2) provide/enhance knowledge, skills and self-efficacy on RRI preventive behaviours. The programme is aimed to be delivered through an online system.

CONCLUSION

An RRI prevention programme was developed using the IM framework and a participatory approach. The programme was named 'RunIn3', and it is based on providing feedback on running volume and RRI risk, as well as providing knowledge, skills and self-efficacy on RRI preventive behaviours.

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.

Severity of Overuse Injury Impacts Self-Efficacy and Quality of Life in Runners: A 2-Year Prospective Cohort Study

CONTEXT

While 55 million Americans incorporate running into their exercise routines, up to 65% of runners sustain an overuse injury annually. It has been consistently shown that regular physical activity positively impacts quality of life (QOL), an essential public health indicator; however, the impact of running-related injuries on QOL is unknown. This study seeks to determine whether overuse injury severity impacts QOL in recreational runners, and if self-efficacy mediates this relationship.

DESIGN

Community-based prospective cohort study of 300 runners who had been running injury free for at least 5 miles/wk in the past 6 months.

METHODS

Self-efficacy for running and QOL measures (Short Form-12 Physical Component and Mental Component, Satisfaction with Life, Positive Affect and Negative Affect) were assessed at baseline, time of injury, and follow-up visits. Over 2 years of observation, overuse injuries were diagnosed by an orthopedic surgeon and injured runners were referred to a physical therapist.

RESULTS

Injury severity was significantly (P < .01) related with 2 indices of QOL, such that the effect of injury severity was -2.28 units on the Short Form-12 physical component and -0.73 units on positive affect. Self-efficacy accounted for 19% and 48% of the indirect effects on Short Form-12 physical component and positive affect, respectively.

CONCLUSIONS

Since self-efficacy is a modifiable factor related to decreased QOL, these findings have important clinical implications for rehabilitation interventions.

Cost-effectiveness and implementation process of a running-related injury prevention program (RunIn3): Protocol of a randomized controlled trial

Background

Running is one of the most popular and accessible physical activities in the world. However, running-related injuries are unfortunately very common. Scientific evidence is limited and scarce regarding (cost-)effectiveness and implementation process of interventions for running-related injuries prevention. Thus, the objective of this study will be to investigate the effectiveness, cost-effectiveness and implementation process of a running-related injury prevention program (RunIn3).

Methods

This is the protocol of a pragmatic hybrid type 1 randomized controlled trial. There will be 530 runners over 18 years old, without running-related injuries in the last 3 months from São Paulo, Brazil. This program will be delivered online with two broad actions: (1) to provide feedback on individual training characteristics and running-related injury risk; and (2) providing/enhancing knowledge, skills and self-efficacy on running-related injury preventive behaviors. The primary outcome will be the proportion of runners reporting running-related injuries. The secondary outcomes will be preventive behaviors, direct and indirect costs, and implementation outcomes. The main effectiveness analysis on the primary outcome will be performed using linear probability mixed models in order to allow outcome changes over time and to yield the absolute risk reduction between-groups.

Discussion

The main hypothesis of this study is that the RunIn3 program will be effective in reducing the running-related injury risk and in promoting preventive behavior, either by increasing the frequency of healthy behaviors or by reducing the frequency of risk behaviors. Moreover, if the RunIn3 program is effective in reducing the running-related injuries risk, we believe that this effect would go alongside with a reduction of societal costs.

Trail registration

Clinicaltrials.gov (NCT03892239) Registered 5 February 2019 - Prospectively registered, https://clinicaltrials.gov/ct2/show/NCT03892239.

Sex-Specific Differences in Running Injuries: A Systematic Review with Meta-Analysis and Meta-Regression

BACKGROUND

Running is a popular sport with high injury rates. Although risk factors have intensively been investigated, synthesized knowledge about the differences in injury rates of female and male runners is scarce.

OBJECTIVE

To systematically investigate the differences in injury rates and characteristics between female and male runners.

METHODS

Database searches (PubMed, Web of Science, PEDro, SPORTDiscus) were conducted according to PRISMA guidelines using the keywords "running AND injur*". Prospective studies reporting running related injury rates for both sexes were included. A random-effects meta-analysis was used to pool the risk ratios (RR) for the occurrence of injuries in female vs. male runners. Potential moderators (effect modifiers) were analysed using meta-regression.

RESULTS

After removal of duplicates, 12,215 articles were screened. Thirty-eight studies were included and the OR of 31 could be pooled in the quantitative analysis. The overall injury rate was 20.8 (95% CI 19.9-21.7) injuries per 100 female runners and 20.4 (95% CI 19.7-21.1) injuries per 100 male runners. Meta-analysis revealed no differences between sexes for overall injuries reported per 100 runners (RR 0.99, 95% CI 0.90-1.10, n = 24) and per hours or athlete exposure (RR 0.94, 95% CI 0.69-1.27, n = 6). Female sex was associated with a more frequent occurrence of bone stress injury (RR (for males) 0.52, 95% CI 0.36-0.76, n = 5) while male runners had higher risk for Achilles tendinopathies (RR 1. 86, 95% CI 1.25-2.79, n = 2). Meta-regression showed an association between a higher injury risk and competition distances of 10 km and shorter in female runners (RR 1.08, 95% CI 1.00-1.69).

CONCLUSION

Differences between female and male runners in specific injury diagnoses should be considered in the development of individualised and sex-specific prevention and rehabilitation strategies to manage running-related injuries.

Continuous estimation of ground reaction force during long distance running within a fatigue monitoring framework: A Kalman filter-based model-data fusion approach

Estimation of ground reaction forces in runners has been limited to laboratory environments by means of instrumented treadmills, in-ground force plates and optoelectronic systems. Recent advances in estimation techniques using wearable sensors for kinematic analysis and sports performance could enable estimation outside the laboratory. This paper proposes a state-input-parameter estimation framework to continuously estimate the vertical ground reaction force waveform during running. By modeling a runner as a single degree of freedom mass-spring-damper with acceleration measurements at the sacrum a state-space formulation can be applied using Newtonian methods. A dual-Kalman filter is employed to estimate the unmeasured system input which feeds through to an unscented Kalman filter to estimate system dynamics and unknown model parameters (e.g. spring stiffness). For validation, 14 subjects performed three one-minute running trials at three different speeds (self-selected slow, comfortable, and fast) on a pressure-sensor-instrumented treadmill. The estimated vertical ground reaction force waveform parameters; peak vertical ground reaction force (RMSE=6.1-7.2%,ρ=0.95-0.97), vertical impulse (RMSE=8.5-13.0%,ρ=0.50-0.60), loading rate (RMSE=24.6-39.4%,ρ=0.85-0.93), and cadence RMSE<1%,ρ=1.00 were compared against the instrumented treadmill measurements. The proposed state-input-parameter estimation framework could monitor personalized vertical ground reaction force metrics for potential biofeedback applications. The feedback mechanism could provide information about the vertical ground reaction force characteristics to the runner as they are running to provide knowledge of both desirable and undesirable loading characteristics experienced.

Interaction of foot and hip factors identifies Achilles tendinopathy occurrence in recreational runners

OBJECTIVES

To investigate the interaction of ankle-foot complex and hip joint factors with Achilles Tendinopathy (AT) occurrence in recreational runners.

DESIGN

Cross-sectional.

SETTING

Research Laboratory.

PARTICIPANTS

51 runners, 26 healthy and 25 with AT.

MAIN OUTCOMES MEASURES

Shank-forefoot alignment (SFA), weight bearing lunge test (WBLT), passive hip internal rotation (IR) range of motion (ROM), hip external rotators (ER) and ankle plantar flexors (PF) isometric strength. CART analyses were performed to assess interactions that could distinguish those with AT.

RESULTS

Passive hip IR ROM, ankle PF torque, SFA, and hip ER isometric torque were associated AT occurrence. The model correctly classified 92% of individuals without AT and 72% of those with AT. The area under the receiver operating characteristic curve was 0.88. Interaction factors revealed in nodes 3 and 10 were statistically significant. In node 3, runners with more than 29.33° of passive hip IR ROM had a 130% increased likelihood (PR = 2.30) of AT. Node 10 showed that individuals with higher PF torque, SFA varus, ER torque, but reduced passive hip IR ROM had an 87% increased likelihood (PR = 1.87) of AT.

CONCLUSION

Interactions between hip and foot factors could accurately classify recreational runners with and without AT.

How many runners with new-onset Achilles tendinopathy develop persisting symptoms? A large prospective cohort study

BACKGROUND

Achilles tendinopathy (AT) occurs in half of the elite runners. AT is a difficult-to-treat tendon disease, which may progress from new onset to a chronic state. It is unknown how many runners with new-onset AT develop persisting symptoms and which prognostic factors are associated with this course.

OBJECTIVE

To describe how many runners develop persisting symptoms 1 year after onset of reactive AT.

STUDY DESIGN

Prospective cohort study.

METHODS

Runners registering for a Dutch running event (5-42.2 km) were eligible for inclusion. Runners reporting new-onset AT between registration for the running event and 1 month after received a 1-year follow-up questionnaire. The 1-year follow-up questionnaire inquired about persisting symptoms (yes/no), running activity, and metabolic disorders. We calculated the percentage of runners with persisting symptoms and performed a multivariable logistic regression analysis to study the association between potential prognostic factors and persisting symptoms.

RESULTS

Of 1929 participants, 100 runners (5%) reported new-onset AT. A total of 62 runners (62%) filled in the 1-year follow-up questionnaire. Persisting symptoms were reported by 20 runners (32%). A higher running distance per week before new-onset AT was associated with a lower risk of developing persisting symptoms (odds ratio (OR): 0.9, 95% confidence interval (CI): [0.9;1.0]). There was a positive trend toward an association between metabolic disorders and persisting symptoms (OR: 5.7, 95% CI: [0.9;36.2]).

CONCLUSION

One third of runners develop persisting symptoms 1 year after new-onset AT. Interestingly, a higher running distance per week before new-onset AT potentially lowers the risk of developing persisting symptoms.

A Primer on Running for the Orthopaedic Surgeon

Long-distance running has become increasingly popular during the past decades. Many running patients pose questions to their orthopaedic surgeons regarding risks, benefits, and running techniques. This article identifies 11 running-related questions that patients may ask and provides information to help answer those questions. This review discusses data on the health benefits of running, common running injuries, the relationship between running and osteoarthritis, recommendations regarding running after orthopaedic surgery, running shoes, and other questions that may arise when treating the running athlete.

There is no difference in footstrike pattern distribution in recreational runners with or without anterior knee pain

BACKGROUND

There are no studies comparing footstrike pattern distribution between recreational runners with or without anterior knee pain.

OBJECTIVE

The aim of this study was to investigate if there was any difference in footstrike pattern between recreational runners with or without anterior knee pain.

METHODS

This cross-sectional study involved 62 runners without anterior knee pain and 60 runners with anterior knee pain. We recruited runners in public parks and amateur road running competitions. A 2D record was made using a high-speed camera with an acquisition frequency of 300 Hz and shutter speed of 300^s-1. Also, demographic information, running characteristics, knee pain characteristics, and running biomechanics variables were collected. Besides the footstrike pattern, running step length, mean velocity, footstrike angle, and ankle push-off were evaluated.

RESULTS

The distribution of rearfoot strike pattern was similar between groups, observed in 96.6 % of the subjects with anterior knee pain and in 93.5 % of the subjects without it. In the secondary analysis, a logistic regression was conducted, and none of the demographic information, running training characteristics, and running biomechanics variables evaluated in this study were associated with runners presenting knee pain.

CONCLUSION

Runners with or without anterior knee pain do not differ in regard to footstrike pattern. Both groups had predominantly rearfoot strike patterns, and none of the collected variables were associated with anterior knee pain on runners.

Fatigue Induced Changes in Muscle Strength and Gait Following Two Different Intensity, Energy Expenditure Matched Runs

Purpose

To investigate changes in hip and knee strength, kinematics, and running variability following two energy expenditure matched training runs; a medium intensity continuous run (MICR) and a high intensity interval training session (HIIT).

Methods

Twenty (10 Females, 10 Males) healthy master class runners were recruited. Each participant completed the HIIT consisting of six repetitions of 800 m with a 1:1 work: rest ratio. The MICR duration was set to match energy expenditure of the HIIT session. Hip and knee muscular strength were examined pre and post both HIIT and MICR. Kinematics and running variability for hip and knee, along with spatiotemporal parameters were assessed at start and end of each run-type. Changes in variables were examined using both 2 × 2 ANOVAs with repeated measures and on an individual level when the change in a variable exceeded the minimum detectable change (MDC).

Results

All strength measures exhibited significant reductions at the hip and knee (P < 0.05) with time for both run-types; 12% following HIIT, 10.6% post MICR. Hip frontal plane kinematics increased post run for both maximum angle (P < 0.001) and range of motion (P = 0.003). Runners exhibited increased running variability for nearly all variables, with the HIIT having a greater effect. Individual assessment revealed that not all runners were effected post run and that following HIIT more runners had reduced muscular strength, altered kinematics and increased running variability.

Conclusion

Runners exhibited fatigue induced changes following typical training runs, which could potentially present risk of injury development. Group and individual assessment revealed different findings where the use of MDC is recommended over that of P-values.

CrossFit and the Epidemiology of Musculoskeletal Injuries: A Prospective 12-Week Cohort Study

Background:

Despite the increasing international popularity of CrossFit, there is a paucity of scientific evidence on the risk of CrossFit-related musculoskeletal injuries (CRMIs).

Purpose:

To investigate the incidence (cumulative incidence proportion [IP] and incidence density [ID]) of CRMIs and the association of CRMIs with personal and training characteristics.

Study Design:

Descriptive epidemiology study.

Methods:

A prospective, 12-week descriptive epidemiology cohort study was conducted in a convenience sample of CrossFit facilities in a single Brazilian city. Printed baseline questionnaires were distributed to 13 CrossFit boxes. All participants who filled out the questionnaire and consented to participate in the study were invited to respond to an online follow-up questionnaire every 2 weeks to collect data on CrossFit training characteristics and CRMIs. A CRMI was defined as any self-reported musculoskeletal injury or pain that prevented an athlete from exercising for at least 1 day. The IP was defined as the number of new cases divided by the entire population at risk, while the ID was defined as new events divided by the total person-time exposure in hours. Logistic mixed models were developed to investigate the association of CRMIs with personal and training characteristics.

Results:

A total of 515 CrossFit participants filled out the baseline questionnaire and provided informed consent, and 406 (78.8%) completed at least 1 follow-up measure. There were 133 participants who reported at least 1 CRMI during the study, and a total of 247 unique and new CRMIs were reported over a total estimated person-time exposure to CrossFit of 13,041 hours. The IP was 32.8% (95% CI, 28.4%-37.5%). The ID was 18.9 (95% CI, 16.6-21.3) per 1000 hours of CrossFit exposure. The shoulders (19.0%; n = 47) and lumbar spine (15.0%; n = 37) were most affected. Muscle injuries (45.3%; n = 112) and joint pain (24.7%; n = 61) were the most common CRMI types reported. Switching between prescribed and scaled down training loads (odds ratio [OR], 3.5 [95% CI, 1.7-7.3]) and previous injuries (OR, 3.2 [95% CI, 1.4-7.7]) were risk factors for a CRMI, while CrossFit experience was identified as a protective factor (OR, 0.7 [95% CI, 0.5-1.0]).

Conclusion:

In this 12-week prospective study, the ID was 18.9 CRMIs per 1000 hours of exposure; switching between training loads and previous injuries was associated with 3.5- and 3.2-fold higher odds, respectively, of sustaining CRMIs.

Are Functional Movement Screen Tests Performed at the Right Time, if It Is an Injury Risk Predictor?

CONTEXT

Sports injuries are more common when players are fatigued and occur more frequently at the end of matches; therefore, determining the right time for employing an injury screening test is important.

OBJECTIVE

To determine the role of timing (prematch vs postmatch fatigue) on the functional movement screen (FMS) scores, a frequently used injury risk screening method.

DESIGN

Cross-sectional study.

SETTING

Field.

PARTICIPANTS

Twenty-four women soccer players from a professional team were included.

MAIN OUTCOME MEASURES

The players were evaluated with a visual analog scale for perceived fatigue and with the FMS. Assessments were conducted before and after a 60-minute match.

RESULTS

The subtest scores for deep squat, hurdle line, in-line lunge, trunk stability push-up, and the total FMS scores showed a significant decrease following the match (P < .05). Compared with prematch, the number of players who could achieve the highest score of 3/3 postmatch was lower for all subtests except right shoulder mobility.

CONCLUSIONS

Our results suggest a negative relationship between perceived fatigue level and performance on the deep squat, hurdle line, in-line lunge, and trunk stability push-up subtest scores and in the total FMS score. Therefore, the authors suggest that screening tests such as the FMS should be employed following a match when players present with fatigue.

Running Themselves Into the Ground? Incidence, Prevalence, and Impact of Injury and Illness in Runners Preparing for a Half or Full Marathon

OBJECTIVE

To describe the incidence, prevalence, and impact of running-related injuries (RRIs) and illness symptoms in half marathon and marathon runners during the 16-week period before the Utrecht Marathon.

METHODS

In this prospective cohort study, we used the Oslo Sports Trauma Research Center questionnaire to register RRIs and illness symptoms every 2 weeks during the 16-week study period. When an injury or illness occurred, questions were added regarding its nature. We calculated the incidence proportion (the number of new cases divided by the number of runners at risk) and the period prevalence (the number of existing and new cases within a 2-week period, divided by the total number of runners at risk during that period).

RESULTS

Of the 161 included runners, 9 out of 10 reported an RRI or illness symptom at some time during the study period. In any 2-week period, 5.6% to 14.8% of the runners reported a new RRI, and 6.3% to 13.8% of the runners reported a new illness symptom. The prevalence of RRIs ranged from 29.2% to 43.5%, and the prevalence of illness symptoms ranged from 28.3% to 71.2%. The most prevalent RRIs were in the lower leg (prevalence range, 5.4%-12.3%) and knee (prevalence range, 2.7%-9.3%). The most prevalent illness symptoms were rhinorrhea/sneezing (prevalence range, 3.9%-12.7%) and coughing (prevalence range, 3.9%-11.9%). The incidence and prevalence of illness symptoms peaked at the same time as the influenza-like illness epidemic of the winter of 2015-2016.

CONCLUSION

Nine out of every 10 runners reported an RRI or illness symptom in the lead-up to a half or full marathon. In any 2-week period, up to 1 in 7 runners reported a new RRI or illness symptom.

LEVEL OF EVIDENCE

2b. J Orthop Sports Phys Ther 2019;49(7):518-528. doi:10.2519/jospt.2019.8473.

Effects of tailored advice on injury prevention knowledge and behaviours in runners: Secondary analysis from a randomised controlled trial

OBJECTIVES

To determine whether biweekly tailored advice was more effective than general advice at baseline alone for enhancing evidence-based running-related injury (RRI) prevention knowledge and behaviours in runners.

DESIGN

Randomised controlled trial, blinded statistical analysis, secondary analysis.

SETTING

Recreational running clinics.

PARTICIPANTS

Running clinics were cluster randomised into intervention or control groups. All participants (n = 51) received general RRI prevention advice (baseline), after which the intervention group (n = 31) received additional biweekly tailored advice (weeks 3-11), before all participants completed a Final Questionnaire (week 13).

MAIN OUTCOME MEASURES

Between-group differences in change of evidence-based RRI prevention knowledge and behaviours.

RESULTS

Compared to baseline, the number of correct knowledge responses significantly increased in the intervention group (5.77, 95% CI 4.73, 6.81) and remained unchanged in controls (0.25, 95% CI -1.04, 1.55), outlining a positive effect only in the intervention group (p = 2.06 × 10^-8). The number of correct behaviour responses significantly increased in the intervention group (1.94, 95% CI 0.94, 2.93) however this increase was not significantly greater than controls (p = 0.075).

CONCLUSIONS

Biweekly tailored advice improved RRI prevention knowledge in runners. Further research into the impact of knowledge and behavioural change on RRI occurrence is warranted. ISRCTN 17357362.

PREVALENCE OF INJURIES IN BRAZILIAN RECREATIONAL STREET RUNNERS: META-ANALYSIS

ABSTRACT Street running is an accessible, low-cost form of exercise. However, the occurrence of musculoskeletal injuries may hinder regular practice. This study aimed at estimating the prevalence of injuries in Brazilian street runners and the associated factors. A meta-analysis of Brazilian studies was performed to investigate the prevalence and risk factors of injuries in male and female recreational street runners aged ≥18 years. We excluded systematic review studies, research conducted on professional athletes or triathletes, and duplicate articles. The following databases were used: SciELO, LILACS, PubMed, Web of Science, and Google Scholar. Keywords such as “prevalence,” “injury,” “recreational street runners,” and “Brazil” were used. Prevalence analysis was performed using the random effect model, and a funnel plot was used to assess publication bias. Then the Begg-Mazumdar and Egger tests were applied to quantify the graph results. The Prevalence Critical Appraisal Instrument was used to evaluate the methodological quality of the studies. Associated factors were analyzed with meta-regression analysis. Twenty-three studies with 3,786 runners were included in the review. The prevalence of injury was 36.5% (95% confidence interval [CI] 30.8-42.5%), and a running distance per week greater than 20 km was a predictive variable of injuries. A higher prevalence of injuries was observed in men than in women (28.3%, 95% CI 22.5-35.0%), the knee was the most affected site of injury (32.9%, 95% CI 26.7-39.6%), and muscle injuries were the most frequent type of injury (27.9%, 95% CI 18.2-40.1%). This is the first national meta-analysis conducted to investigate the prevalence of injuries in recreational street runners. Although the prevalence of injuries was moderate, caution is required in terms of the weekly duration of running. Male runners are more susceptible, and muscle and knee injuries are the most common. Level of evidence II, Systematic reviewb of Level II Studies.

'Take a Mental Break!' study: Role of mental aspects in running-related injuries using a randomised controlled trial

Background

Running-related injuries (RRIs) can be considered the primary enemy of runners. Most literature on injury prediction and prevention overlooks the mental aspects of overtraining and under-recovery, despite their potential role in injury prediction and prevention. Consequently, knowledge on the role of mental aspects in RRIs is lacking.

Objective

To investigate mental aspects of overtraining and under-recovery by means of an online injury prevention programme.

Methods and analysis

The ‘Take a Mental Break!’ study is a randomised controlled trial with a 12 month follow-up. After completing a web-based baseline survey, half and full marathon runners were randomly assigned to the intervention group or the control group. Participants of the intervention group obtained access to an online injury prevention programme, consisting of a running-related smartphone application. This app provided the participants of the intervention group with information on how to prevent overtraining and RRIs with special attention to mental aspects. The primary outcome measure is any self-reported RRI over the past 12 months. Secondary outcome measures include vigour, fatigue, sleep and perceived running performance. Regression analysis will be conducted to investigate whether the injury prevention programme has led to a lower prevalence of RRIs, better health and improved perceived running performance.

Ethics and dissemination

The Medical Ethics Committee of the University Medical Center Utrecht, the Netherlands, has exempted the current study from ethical approval (reference number: NL64342.041.17). Results of the study will be communicated through scientific articles in peer-reviewed journals, scientific reports and presentations on scientific conferences.

Prevalência de lesão e fatores associados em corredores de rua da cidade de Juiz de Fora (MG)

RESUMO No Brasil, a corrida de rua é o segundo esporte mais praticado; entretanto, pode ocasionar lesões musculoesqueléticas. Estudos sobre o tema são importantes para nortear estratégias de prevenção e intervenção. Assim, o objetivo foi investigar a prevalência de lesões e os fatores associados em corredores de rua da cidade de Juiz de Fora(MG). Trata-se de um estudo observacional do tipo transversal. A amostra foi selecionada por conveniência. Foram incluídos corredores amadores, entre 18 e 60 anos e que realizavam treinos em diferentes locais da cidade. Foram excluídos participantes com histórico de fratura e osteossíntese em membros inferiores ou que praticassem outro esporte que não fosse a musculação. Para analisar os dados, foram utilizados os testes t de Student, Mann-Whitney e X2 (α=0,05). Os participantes foram alocados em grupo lesão (GL, n=37) e grupo sem lesão (GSL, n=113). A prevalência de lesão foi de 24,7%. O GL praticava a corrida há mais tempo (76,2 ± 9,1 × 36,7 ± 39,0 meses; P<.01), teve menor aumento da frequência semanal do treinamento (49,5% × 54,2%; P=.04), realizou menos alongamento prévio (48,6% × 75,2%; P=.02), apresentou maior percentual de análise da marcha para escolha do calçado (62,1% × 43,3%; P=.04) e uso de palmilha (35,1% X 14,1%; P=<.01). A prevalência de lesões foi baixa. Os que correm há mais tempo têm maior risco de lesão mesmo sem incremento na frequência semanal. O alongamento foi protetor e a prescrição de calçado e palmilha indiscriminados não garantiram resultados satisfatórios.

Functional Movement Screening and Injury Rates in High School and Collegiate Runners: A Retrospective Analysis of 3 Prospective Observational Studies

OBJECTIVE

Determine if the Functional Movement Screening (FMS) can be used to predict injury in high school and collegiate cross-country and track runners.

DESIGN

Prospective Observational, Cohort Study, Level of Evidence, 2.

SETTING

High schools and colleges in the Central Ohio area.

PATIENTS

Inclusion: (1) cross-country or track runners at participating schools; (2) full participation without restrictions; and (3) signed informed assent or consent. Exclusion: (1) Any injury or lower extremity surgery within 30 days; (2) planned limited participation in the upcoming season; or (3) other participation restrictions.

INTERVENTIONS

Functional Movement Screening was completed before the start of each season. Injuries were tracked during the regular season. No interventions were made based on FMS score.

MAIN OUTCOME MEASURES

Functional Movement Screening scores, including overall, lower extremity, and specific exercises were compared between runners who did and did not sustain an injury using 2 sample t tests. A cutoff FMS score of ≤14 (most common in previous studies), and ≤15 (determined by a receiver operating characteristic curve), were compared using χ tests.

RESULTS

One hundred eighty-three runners were enrolled in the study. Overall, 32 (17.5%) runners sustained an injury. Functional Movement Screening score was not accurate in predicting injury for ≤14 (sensitivity: 65.6%; specificity: 39.7%; and area under the curve = 0.501) or ≤15 (sensitivity: 84.4% and specificity: 23.8%). There was no difference in risk of injury for runners with a FMS score of ≤14 (15.5%) and >14 (18.8%) (P = 0.572) or with a FMS score of ≤15 (17.5%) and >15 (17.4%) (P = 0.988).

CONCLUSIONS

Functional Movement Screening composite score may not be useful for injury prediction in populations of high school and collegiate runners.

Study protocol of a 52-week Prospective Running INjury study in Gothenburg (SPRING)

INTRODUCTION

It is assumed that a running-related (overuse) injury occurs when a specific structure of the human body is exposed to a load that exceeds that structures' load capacity. Therefore, monitoring training load is an important key to understanding the development of a running-related injury. Additionally, other distribution, magnitude and capacity-related factors should be considered when aiming to understand the causal chain of injury development. This paper presents a study protocol for a prospective cohort study that aims to add comprehensive information on the aetiology of running-related injuries and present a new approach for investigating changes in training load with regard to running-related injuries.

METHODS AND ANALYSIS

This study focused on recreational runners, that is, runners exposed to a minimum weekly average of 15 km for at least 1 year. Participants will undergo baseline tests consisting of a clinical/anthropometrical examination and biomechanical measurements. Furthermore, participants will log all training sessions in a diary on a weekly basis for 1 year. The primary exposure variable is changes in training load. A medical practitioner will examine runners suffering from running-related pain and, if possible, make a clear diagnosis. Finally, additional time-varying exposure variables will be included in the main analysis, whereas the analysis for the secondary purpose is based on time-fixed baseline-related risk factors.

ETHICS AND DISSEMINATION

Ethical approval (DNR: 712-15) for the study and its design was obtained from the Gothenburg regional ethical review board. The results of the study will be published in peer-reviewed journals.

Health and Economic Burden of Running-Related Injuries in Dutch Trailrunners: A Prospective Cohort Study

Background

Trailrunning is becoming very popular. However, the risk and burden of running-related injuries (RRI) in trailrunning is not well established.

Objective

To investigate the prevalence, injury rate, severity, nature, and economic burden of RRIs in Dutch trailrunners.

Methods

This prospective cohort study included 228 trailrunners aged 18 years or over (range 23–67), and was conducted between October 2013 and December 2014. After completing the baseline questionnaire, the Oslo Sports Trauma Research Center Questionnaire on Health Problems was administered every 2 weeks to collect data on RRIs. Participants who reported RRIs were asked about healthcare utilization (direct costs) and absenteeism from paid work (indirect costs). RRI was defined as disorders of the musculoskeletal system or concussions experienced or sustained during participation in running.

Results

The mean prevalence of RRIs measured over time was 22.4 % [95 % confidence interval (CI) 20.9–24.0], and the injury rate was 10.7 RRIs per 1000 h of running (95 % CI 9.4–12.1). The prevalence was higher for overuse (17.7 %; 95 % CI 15.9–19.5) than for acute (4.1 %; 95 % CI 3.3–5.0) RRIs. Also, the injury rate was higher for overuse (8.1; 95 % CI 6.9–9.3) than for acute (2.7; 95 % CI 2.0–3.4) RRIs. The median of the severity score was 35.0 [25–75 %, interquartile range (IQR) 22.0–55.7], and the median of the duration of RRIs was 2.0 weeks (IQR 2.0–6.0) during the study. The total economic burden of RRIs was estimated at €172.22 (95 % CI 117.10–271.74) per RRI, and €1849.49 (95 % CI 1180.62–3058.91) per 1000 h of running. An RRI was estimated to have a direct cost of €60.92 (95 % CI 45.11–94.90) and an indirect cost of €111.30 (95 % CI 61.02–192.75).

Conclusions

The health and economic burden of RRIs presented in this study are significant for trailrunners and for society. Therefore, efforts should be made in order to prevent RRIs in trailrunners.

Electronic supplementary material

The online version of this article (doi:10.1007/s40279-016-0551-8) contains supplementary material, which is available to authorized users.

Treatment Success of Hip and Core or Knee Strengthening for Patellofemoral Pain: Development of Clinical Prediction Rules

CONTEXT

  Patellofemoral pain (PFP) is a common injury that interferes with quality of life and physical activity. Clinical subgroups of patients may exist, one of which is caused by proximal muscle dysfunction.

OBJECTIVES

  To develop clinical prediction rules that predict a positive outcome after either a hip and core- or knee-focused strengthening program for individuals with PFP.

DESIGN

  Secondary analysis of data from a randomized control trial.

SETTING

  Four university laboratories.

PATIENTS OR OTHER PARTICIPANTS

  A total of 199 participants with PFP.

INTERVENTION(S)

  Participants were randomly allocated to either a hip and core-focused (n = 111) or knee-focused (n = 88) rehabilitation group for a 6-week program.

MAIN OUTCOME MEASURE(S)

  Demographics, self-reported knee pain (visual analog scale) and function (Anterior Knee Pain Scale), hip strength, abdominal muscle endurance, and hip range of motion were evaluated at baseline. Treatment success was defined as a decrease in visual analog scale score by ≥2 cm or an increase in the Anterior Knee Pain Scale score by ≥8 points or both. Bivariate relationships between the outcome (treatment success) and the predictor variables were explored, followed by a forward stepwise logistic regression to predict a successful outcome.

RESULTS

  Patients with more pain, better function, greater lateral core endurance, and less anterior core endurance were more likely to have a successful outcome after hip and core strengthening (88% sensitivity and 54% specificity). Patients with lower weight, weaker hip internal rotation, stronger hip extension, and greater trunk-extension endurance were more likely to have success after knee strengthening (82% sensitivity and 58% specificity).

CONCLUSION

  The patients with PFP who have more baseline pain and yet maintain a high level of function may experience additional benefit from hip and core strengthening. The clinical prediction rules from this study remain in the developmental phase and should be applied with caution until externally validated.

Accelerometer-based prediction of running injury in National Collegiate Athletic Association track athletes

Running-related injuries (RRI) may result from accumulated microtrauma caused by combinations of high load magnitudes (vertical ground reaction forces; vGRFs) and numbers (strides). Yet relationships between vGRF and RRI remain unclear - potentially because previous research has largely been constrained to collecting vGRFs in laboratory settings and ignoring relationships between RRI and stride number. In this preliminary proof-of-concept study, we addressed these constraints: Over a 60-day period, each time collegiate athletes (n = 9) ran they wore a hip-mounted activity monitor that collected accelerations throughout the entire run. Accelerations were used to estimate peak vGRF, number of strides, and weighted cumulative loading (sum of peak vGRFs weighted to the 9th power) across the entirety of each run. Runners also reported their post-training pain/fatigue and any RRI that prevented training. Across 419 runs and >2.1 million strides, injured (n = 3) and uninjured (n = 6) participants did not report significantly different pain/fatigue (p = 0.56) or mean number of strides per run (p = 0.91). Injured participants did, however, have significantly greater peak vGRFs (p = 0.01) and weighted cumulative loading per run (p < 0.01). Results from this small but extensively studied sample of elite runners demonstrate that loading profiles (load magnitude-number combinations) quantified with activity monitors can provide valuable information that may prove essential for: (1) testing hypotheses regarding overuse injury mechanisms, (2) developing injury-prediction models, and (3) designing and adjusting athlete- and loading-specific training programs and feedback.

The Influence of Injury Definition on Injury Burden in Preprofessional Ballet and Contemporary Dancers

Study Design Cohort study. Background Multiple operational definitions of injury exist in dance research. The influence that these different injury definitions have on epidemiological estimations of injury burden among dancers warrants investigation. Objective To describe the influence of injury definition on injury prevalence, incidence, and severity in preprofessional ballet and contemporary dancers. Methods Dancers registered in full-time preprofessional ballet (n = 85; 77 female; median age, 15 years; range, 11-19 years) and contemporary (n = 60; 58 female; median age, 19 years; range, 17-30 years) training completed weekly online questionnaires (modified Oslo Sports Trauma Research Centre questionnaire on health problems) using 3 injury definitions: (1) time loss (unable to complete 1 or more classes/rehearsals/performances for 1 or more days beyond onset), (2) medical attention, and (3) any complaint. Physical therapists completed injury report forms to capture dance-related medical attention and time-loss injuries. Percent agreement between injury registration methods was estimated. Injury prevalence (seasonal proportion of dancers injured), incidence rates (count of new injuries per 1000 dance-exposure hours), and severity (total days lost) were examined across each definition, registration method, and dance style. Results Questionnaire response rate was 99%. Agreement between registration methods ranged between 59% (time loss) and 74% (injury location). Depending on definition, registration, and dance style, injury prevalence ranged between 9.4% (95% confidence interval [CI]: 4.1%, 17.7%; time loss) and 82.4% (95% CI: 72.5%, 89.8%; any complaint), incidence rates between 0.1 (95% CI: 0.03, 0.2; time loss) and 4.9 (95% CI: 4.1, 5.8; any complaint) injuries per 1000 dance-hours, and days lost between 111 and 588 days. Conclusion Time-loss and medical-attention injury definitions underestimate the injury burden in preprofessional dancers. Accordingly, injury surveillance methodologies should consider more inclusive injury definitions. J Orthop Sports Phys Ther 2018;48(3):185-193. Epub 13 Dec 2017. doi:10.2519/jospt.2018.7542 Level of Evidence Symptom prevalence study, level 1b.