A systematic review of running-related musculoskeletal injuries in runners

Restoring tendon microenvironment in tendinopathy: Macrophage modulation and tendon regeneration with injectable tendon hydrogel and tendon-derived stem cells exosomes

Tendinopathy is a common musculoskeletal disorder in which a significant number of patients do not attain effective therapeutic outcomes. The extent of the inflammatory response and the dynamics of collagen synthesis metabolism are critical factors that influence the intrinsic self-repair capacity of tendons. However, the poor microenvironment within the tendon significantly impedes the self-repair process in tendinopathy. In this study, an injectable tendon-derived decellularized extracellular matrix (tdECM) hydrogel was utilized to treat tendinopathy. This hydrogel provides a more cytocompatible microenvironment while retaining certain bioactive factors of native tendon extracellular matrix (ECM), compared to collagen hydrogel. Notably, it was discovered for the first time that the tdECM hydrogel promotes M2 macrophage polarization, thereby exerting an anti-inflammatory effect in vivo. Furthermore, utilizing tdECM as a carrier for the sustained release of tendon-derived stem cells exosomes (TDSCs-Exos), our findings from both in vitro and in vivo studies indicate that the tdECM hydrogel, in conjunction with exosomes, demonstrated a pronounced synergistic enhancement in modulating inflammation, promoting M2 macrophage polarization, and facilitating tendon regeneration and repair efficacy. These results suggest its potential as a promising therapeutic strategy for tendon disorders.

Biomechanical Changes and the Time Course of Recovery in Lower Extremities of Recreational Runners Following a Simulated Treadmill Half-Marathon

BACKGROUND

Providing runners with injury prevention suggestions from a biomechanical perspective is crucial in light of the increased incidence of running-related injuries forecasted with the rising popularity of the half-marathon. Previous research has demonstrated associations between running injuries and patterns of lower extremity biomechanics, as well as indicating that inadequate rest between training sessions can result in injuries and underperformance. However, whether half-marathon running elicits lower extremity biomechanical changes and the recovery time remains largely unclear. This study aimed to investigate the acute changes (pre-run and immediately post-run) and the time course of recovery (pre-run, day 1, and day 2) in neuromuscular function, landing strategies, and lower extremity joint mechanics of recreational runners following a simulated half-marathon protocol on a treadmill.

RESULTS

Compared to pre-half-marathon measurements, we observed significant reductions in concentric (Flexors: Pre: 1.49 ± 0.50Nm/kg, Post: 1.34 ± 0.54Nm/kg, p < 0.001; Extensors: Pre: 2.19 ± 0.73Nm/kg, Post: 2.00 ± 0.82Nm/kg, p < 0.001) and eccentric (Flexors: Pre: 1.67 ± 0.68Nm/kg, Post: 1.34 ± 0.62Nm/kg, p < 0.001; Extensors: Pre: 2.44 ± 0.13Nm/kg, Post: 1.96 ± 0.12Nm/kg, p < 0.001) torques of the knee flexors and extensors, reductions in eccentric knee flexor to concentric knee extensor torque ratios (Pre: 0.78 ± 0.27, Post: 0.68 ± 0.22, p < 0.001), and impaired knee (Pre: 1.6 ± 0.1°, Post: 3.0 ± 0.2°, p < 0.001) and hip (Pre: 1.5 ± 0.2°, Post: 2.6 ± 0.2°, p < 0.001) joint position sense immediately post running. Additionally, we observed an increase in contact time (p = 0.006), decreases in peak vertical ground reaction force (p < 0.001) and impulse (p < 0.001), and changes in lower extremity joint kinematics and kinetics during the stance phase of running immediately after the half-marathon. Most measured parameters recovered within one day, except hip joint position sense, which was restored within two days. By the second day, we also observed super-compensation in thigh muscle torques.

CONCLUSION

The study revealed that simulated treadmill half-marathon induces alterations to neuromuscular function, impacts landing strategies, and elicits changes in lower extremity joint mechanics. However, these effects are temporary and resolve within two days post-run. These findings provide valuable insights to optimize training responses and prevent overtraining in recreational runners.

Global prevalence and pattern of injuries in basketball players: a systematic review

INTRODUCTION

Basketball, as a widely popular sport, can be associated with a high risk of injury. This study aimed to provide a comprehensive overview of basketball-related injuries in various groups through the utilization of a systematic review methodology.

EVIDENCE ACQUISITION

An extensive search was conducted in the four valid databases using three groups of keywords up to November 2023 based on the PRISMA guidance. Two reviewers independently performed the steps of the study, including study selection, data extraction, and quality assessment. In case of any disagreements, the opinion of a third researcher was sought to achieve agreement in each step. The agreement between the reviewers was examined by computing Cohen's kappa coefficient. The quality assessment of the articles in this study was conducted using the Joanna Briggs Institute (JBI) critical appraisal tools.

EVIDENCE SYNTHESIS

The prevalence range of injuries in these people was between 0.38% and 92.0%. Ankle injuries in 12 out of 28 studies (42.86%), knee injuries in 7 out of 28 studies (25.00%), head and tooth injuries in 3 out of 28 studies (10.71%), and shoulder and hand injuries in three out of 28 studies (10.71%) had the highest prevalence among various injuries. Five out of six studies (83.33%) showed a higher percentage of the injuries in males. Only a study compared the prevalence of injuries between people with various ages.

CONCLUSIONS

These findings emphasize the need for injury prevention and management strategies, particularly targeting vulnerable areas like the ankle and knee.

Quantifying frontal plane knee thrust in patients with medial knee osteoarthritis using weight transfer and balance tasks

BACKGROUND

Frontal plane instability and chronic pain are common, particularly in older adults with knee osteoarthritis. Previous literature has quantified frontal plane knee thrusts (varus or valgus) during gait, but not during a balance task. This may be relevant to the clinical assessment of people with knee problems, as for some, gait may be too impaired for analysis. The present study aimed to determine the relevance of the proposed measures of knee thrust assessed during a weight transfer and balance task. We hypothesised that the knee thrusts quantified would be sensitive to the presence and severity of osteoarthritis and have high repeatability between trials, which is critical for patient monitoring.

METHODS

Forty-nine older adults (mean 63.8 ± 7.4 years) with (n = 33) or without (n = 16) knee osteoarthritis performed a total of six frontal plane weight-bearing transfer trials in a single-leg standing task. Motion analysis, performed using a non-invasive exoskeleton setup and optoelectronics, focused on the frontal plane knee angles at specific timepoints during the task to extract varus-valgus thrust measures and their magnitude (absolute values). The sensitivity of the measures to the presence and severity of knee osteoarthritis and their repeatability between trials were determined. Correlations between the relevant thrust measures, frontal plane range of motion and the WOMAC pain, function, and stiffness subscales were also computed.

RESULTS

Results show that the |Peak-2 %BW| measure of thrust (absolute values) is sensitive to disease and its severity and has high repeatability between trials. The Peak-2 %BW measure (in varus/valgus direction) was significantly correlated with the WOMAC function and stiffness subscales.

SIGNIFICANCE

This study highlights that a weight transfer and balance task is effective in quantifying frontal thrusts in knee osteoarthritis. Both relative and absolute measures may be relevant for clinical follow-up.

Diet, risk of disordered eating and running-related injury in adult distance runners: A systematic review and meta-analysis of prospective cohort studies

OBJECTIVES

To determine whether diet and disordered eating risk contribute to running-related injury risk in adult (≥18 years) distance runners.

DESIGN

Systematic review and meta-analysis.

METHODS

Random effects meta-analyses of prospective cohort studies compared dietary intake and disordered eating risk in distance runners with and without running-related injury. Quality of evidence was assessed using an adapted Grading of Recommendations Assessment, Development and Evaluation approach.

RESULTS

Fifteen studies (n = 5942 runners, 2364 female) were included, with nine studies in the meta-analyses. Sex differences were observed for total energy and total fat intake (both p = 0.01). Moderate certainty evidence indicated injured female runners had lower energy and fat intake than uninjured runners (mean difference [95 % confidence interval] = -449 kcal/day [-696, -202] and -20 g/day [-31, -9], respectively, both p < 0.001). Moderate certainty evidence suggested injured runners (combined sexes) had lower dietary fibre intake compared to uninjured runners (-3 g/day [-5, -0], p = 0.04). Other dietary factors (protein, carbohydrate, calcium, alcohol intake and disordered eating risk) did not influence injury risk (low-moderate certainty evidence).

CONCLUSIONS

Moderate certainty evidence indicates female distance runners with lower energy and total fat intakes are at increased risk of running-related injury, as are runners (combined sexes) with lower dietary fibre intake. Future research should include long duration, high quality prospective cohort studies in male and female runners with clearly defined athletic abilities, consistent injury definition, and standardised statistical analyses.

REVIEW REGISTRATION

PROSPERO # CRD42022323627.

Bone Stress Injury Epidemiology and Risk Factors in Female Off-Road Runners: A Systematic Review

BACKGROUND

Off-road running is a growing sport with little research investigating injury profiles of female participants. Bone stress injuries (BSIs) are a particularly detrimental injury with little known about their incidence and risk factors in female off-road runners.

OBJECTIVE

Collate and review the available evidence reporting epidemiological data and risk factors associated with BSI in female off-road runners.

DESIGN

Systematic literature review, without meta-analyses.

DATA SOURCES

MEDLINE OVID, PubMed, SPORTDiscus, and MEDLINE EBSCO. Searches were finalized in July 2024.

ELIGIBILITY CRITERIA

Studies that reported injury surveillance statistics and/or risk factors associated with BSIs in female off-road runners.

RESULTS

Seventeen eligible studies were included, of which all reported surveillance statistics and 2 reported risk factors associated with BSI among 897 female runners. Owing to the scarcity of data, cross-country runners were included in the population of off-road runners. Most BSIs were high severity and in the lower leg, with an overall incidence ranging from 0 to 34.39 BSIs per 100,000 athlete-exposures and prevalence ranging from 0% to 40.9%. Study characteristics were reported alongside risk of bias, quality, and level of evidence assessment outcomes from varying tools. Eight significant intrinsic risk factors were associated with BSIs in female off-road runners: increasing age, disrupted menstruation, previous BSI, increased female triad risk, and lower calcium, vitamin D, and calorie intake.

DISCUSSION

Limited by the number of studies available reporting data on the specific target population, which highlights the need for performing high-quality prospective studies in the future, this review summarizes the current epidemiological data and risk factors associated with BSIs in female off-road runners.

Predictors of pelvic acceleration during treadmill running across various stride frequency conditions

Pelvic running injuries often require extensive rehabilitation and pelvic girdle pain is a barrier to running engagement in population sub-groups, such as perinatal women. However, exploration into how external pelvic loading may be altered during running is limited. This study assessed which biomechanical variables influence changes in external peak pelvic acceleration during treadmill running, across various stride frequency conditions. Twelve participants (7 female, 5 male) ran (9 km∙h-1) at their preferred stride frequency, and at ± 5% and ± 10% of their preferred stride frequency. Coordinate and acceleration data were collected using a motion capture system and inertial measurement units. Linear mixed models assessed peak tibial acceleration, displacement from hip to knee and ankle, contact time, and stride frequency as predictors of peak pelvic acceleration. Stride frequency and contact time interacted to predict peak vertical (p = .006) and resultant (p = .009) pelvic acceleration. When modelled, short contact times and low stride frequencies produced higher peak vertical (p = .007) and resultant (p = .016) pelvic accelerations than short contact times and average, or high stride frequencies. Increasing contact time, or increasing stride frequency at shorter contact times, may therefore be useful in reducing pelvic acceleration during treadmill running.

The effects of telehealth running gait retraining on biomechanics, pain, and function in patients with lower extremity injuries: A randomized clinical trial

BACKGROUND

In-clinic gait retraining has been effective in modifying suspected biomechanical risk factors for running injury, but its feasibility is often limited by multiple clinic visits. This randomized clinical trial investigated the effects of a telehealth-based gait retraining intervention on running biomechanics, pain, and function in previously injured runners.

METHODS

Twenty-three participants recovering from lower extremity injuries were randomized to a control or intervention group. The intervention group completed 4 to 6 telehealth gait retraining sessions over 8 to 10 weeks, consisting of visual and verbal cues to transition to a non-rearfoot strike pattern and increase step rate. The control group received standard physical therapy. Biomechanics, pain, and function were assessed pre- and post-intervention using a 2 × 2 mixed model analysis of variance.

FINDINGS

Half of the participants (55 %) in the intervention group successfully transitioned to a non-rearfoot strike pattern. No significant differences were observed between groups in step rate, biomechanics, or function. A significant group-by-time interaction for pain was observed (F = 10.55, P = 0.004), with the intervention group reporting greater reductions in pain compared to the control group (mean difference 2.52, 95 % CI 0.91 to 4.12).

INTERPRETATION

Despite only half of participants adopting the desired gait pattern, telehealth gait retraining may offer a low-risk, accessible, and convenient alternative for select patients who lack in-person care options or have not responded to other pain reduction methods when returning to running from a lower extremity injury.

Using complex systems to understand running-related injuries

This study aims to investigate anthropometric and training characteristics associated with injuries in runners using a complex approach. We conducted a cross-sectional study with 97 Brazilian runners of both sexes (age: 39.1 ± 11.5 years; body mass index: 24.2 ± 4.2 kg/m2). A web survey was used for data collection, including age, sex, body weight, body height, training volume/frequency, session duration, running pace and injury information (yes or no; the number of injuries). The partial correlation parameter was used for network estimation, considering both sexes. For women, injury occurrence was positively and strongly associated with training frequency (r = 0.57) and the number of competitions (r = 0.64), while for men, a negative and strong association was found with age (r=-0.69), and positive associations were observed with BMI (r = 0.89) and training volume (r = 0.82). Network centrality showed that training session duration and the number of competitions/year presented a higher expected influence value for women (-1.47) and men (-1.31). Using a non-linear approach with Brazilian non-professional runners, training characteristics had a stronger influence on running-related injuries.

Exploring the use of digital technology for injury prevention and self-management among recreational runners

OBJECTIVES

Explore digital technology use among recreational runners in Wales and assess attitudes toward a proposed digital intervention for running-related injury (RRI) prevention and self-management.

DESIGN

Exploratory survey.

SETTING

Online questionnaire, closed questions distributed to runners over a 7 week period.

PARTICIPANTS

Recreational runners living in Wales (N = 232).

MAIN OUTCOME MEASURES

Data analysed descriptively. Inferential analysis conducted via IBM SPSS v25. Pearson's Chi square and logistic regression applied to assess effects of age, sex, and weekly mileage on technology use.

RESULTS

97% of participants reported using digital technology to monitor training, primarily through running watches (45.1%) and smartphone apps (37.6%). Pearson's chi square indicated that younger (18-24 years) and less experienced runners (3 months-2 years) were more likely to use multiple apps. Runners felt these technologies did not offer realistic advice for RRI prevention or self-management. Most runners (84.5%) were interested in the proposed intervention. Runners wanted to see injury advice, exercises to improve running and a diagnostic feature within the proposed intervention.

CONCLUSION

Digital technologies are widely used by recreational runners but are not perceived as useful for injury prevention/self-management. There is therefore an opportunity to develop tailored, evidence-based digital interventions for RRI prevention and self-management.

Effect of physiotherapy interventions on pain management, function and quality of life in patellofemoral pain syndrome: A systematic review protocol

BACKGROUND

Patellofemoral pain syndrome (PFPS) is a prevalent and often debilitating condition, affecting approximately 22.7% of the population and significantly contributing to knee-related disorders. It primarily impacts young athletes and sedentary individuals, impairing their quality of life and functional abilities. Despite extensive research, the optimal management strategies for PFPS remain contentious due to its multifactorial etiology and persistent symptoms. The findings of this review will guide clinical practice and future research, ultimately improving outcomes for individuals with PFPS.

OBJECTIVE

This systematic review aims to evaluate the effectiveness of physiotherapy interventions in alleviating pain, enhancing functional outcomes, and improving the quality of life among runners who have been diagnosed with PFPS.

METHODS

This review will be carried out on randomized controlled trials (rcts) that assess any type of physiotherapy intervention for PFPS in runners. Eligible studies must report on pain intensity, functional improvement, or quality of life outcomes. Searches will be conducted in pubmed/MEDLINE, Cochrane Library, and pedro, covering publications from May 2014 to April 2024. Two reviewers will independently screen and select studies, extract data, and assess quality using the Cochrane Risk of Bias tool. We will perform a narrative synthesis of the data, focusing on pain management, functional recovery, and quality of life improvements. Sensitivity and subgroup analyses will explore variations across study designs and participant characteristics.

CONCLUSION

This systematic review protocol seeks to identify effective physiotherapy interventions for managing PFPS in runners. By analyzing rcts, the review will provide evidence-based recommendations to reduce pain, improve function, and enhance quality of life. The findings will guide clinical decisions.

SYSTEMATIC REVIEW REGISTRATION

International Prospective Register of Systematic Reviews (PROSPERO) under ID: CRD42024531888. Date- 7/05/2024, URL https://www.crd.york.ac.uk/prospero/#recorddetails.

Running Distance and Biomechanical Risk Factors for Plantar Fasciitis: A One-Year Prospective 4HAIE Cohort Study

INTRODUCTION

Plantar fasciitis (PF) is one of the most common running-related injuries.

PURPOSE

The aim of this prospective study was to determine the incidence of PF and identify potential risk or protective factors for PF in runners and non-runners.

METHODS

Data from 1206 participants from the 4HAIE cohort study (563 females/643 males; 715 runners/491 non-runners; 18-65 years of age) were included in the analysis. We collected biomechanical data during overground running using a 3-D motion capture system at the baseline and running distance data via retrospective questionnaires and followed the participants for 12 months following the baseline data collection. Participants were asked weekly about any sports-related injury (including PF). A binary logistic regression was performed to reveal potential associations between running distance and biomechanical risk factors and PF while controlling for running distance, sex, and age.

RESULTS

The total incidence of PF was 2.3% (28 PF from 1206 participants), 2.5% in runners and 2.0% in non-runners (P = 0.248). Runners who ran more than 40 km per week had six times higher odds of suffering PF than individuals who ran 6-20 km/week (P = 0.009). There was a significant association between maximal ankle adduction and PF, that is, runners with a lower abduction angle during the stance period had higher risk of PF (P = 0.024). No other biomechanical variables indicated significant associations with PF.

CONCLUSIONS

Regular running with a moderate weekly volume and more toeing out of the foot relative to the shank may reduce the risk against PF in runners which may be useful for researchers, runners, coaches, and health professionals to minimize PF injury risk.

Co-creation of injury prevention measures for competitive adolescent distance runners: knowledge, behavior, and needs of athletes and coaches enrolled on England Athletics' Youth Talent Programme

This study assessed the knowledge, behavior, and needs of competitive adolescent (16-18 years) distance runners and distance running coaches enrolled as part of England Athletics' Youth Talent Programme in relation to the prevention of running-related injury (RRI). Two online surveys were developed and distributed to the distance runners (survey one) and coaches (survey two). Both surveys included sections related to: (1) current knowledge; (2) current behavior; (3) need and support for RRI prevention measures; and (4) possible content and form of RRI prevention measures. A total of 39 distance runners (36% of total possible sample) completed survey 1, and 29 coaches (32% of total possible sample) completed survey 2. Key findings included that the majority of distance runners and coaches: (1) agreed that it is 'very important' to try to prevent RRI; (2) are currently implementing something in practice (e.g., strength training) to prevent RRI; and (3) view the creation of RRI prevention measures as an important initiative. Differences between distance runners and coaches were identified in relation to their understanding of the most common causes of RRI. Interestingly, distance runners identified a modifiable cause of RRI (i.e., too much training) as the most common cause of RRI, while coaches selected a non-modifiable cause of RRI (i.e., growth and maturation). These key findings were supplemented by competitive adolescent runners and distance running coaches detailing their delivery preferences for such RRI prevention measures. Results from this study will help inform subsequent steps of the larger co-creation process, with an emphasis on developing multifaceted and context-specific RRI prevention measures that are deemed to be feasible and acceptable for real-world implementation.

The effect of knee braces on knee joint kinematics at different exercise speeds

This study aims to investigate the influence of a new semi-rigid knee joint braces on kinematics using the Opti-knee knee joint kinematic analysis system at various exercise speeds. Twenty-four healthy young male adults were recruited for this study. Participants were randomly assessed while wearing and not wearing knee brace at four different speeds on a treadmill: normal walking (3.6 km/h), brisk walking (5.4 km/h), jogging (9 km/h), and moderate intensity running (10.8 km/h). Six degrees of freedom kinematic data from the knee joint were collected. Paired t-tests were conducted to calculate the kinematic differences. At speeds of 3.6 km/h and 5.4 km/h, wearing the knee brace led to reduced knee joint mobility in anterior-posterior translation, superior-inferior translation, internal-external rotation, and flexion-extension angles during the stance phase (P < 0.05). At 9 km/h, wearing the brace reduced knee joint internal-external rotation and flexion-extension mobility during the stance phase (P < 0.05). At 10.8 km/h, wearing the brace reduced knee joint flexion-extension mobility during the stance phase (P < 0.05). Wearing brace has significant influence on knee kinematics at four speeds, and the effect of brace varies with the speed of movement.

Running Gait Complexity During an Overground, Mass-Participation Five-Kilometre Run

Human locomotion contains innate variability which may provide health insights. Detrended fluctuation analysis (DFA) has been used to quantify the temporal structure of variability for treadmill running, although it has been less commonly applied to uncontrolled overground running. This study aimed to determine how running gait complexity changes in response to gradient and elapsed exercise duration during uncontrolled overground running. Sixty-eight participants completed an overground, mass-participation five-kilometre run (a parkrun). Stride times were recorded using an inertial measurement unit mounted on the distal shank. Data were divided into four consecutive intervals (uphill lap 1, downhill lap 1, uphill lap 2, downhill lap 2). The magnitude (SD) and structure (DFA) of stride time variability were compared across elapsed exercise duration and gradient using a repeated-measures ANOVA. Participants maintained consistent stride times throughout the run. Stride time DFA-α displayed a moderate decrease (d = |0.39| ± 0.13) during downhill running compared to uphill running. DFA-α did not change in response to elapsed exercise duration, although a greater stride time SD was found during the first section of lap 1 (d = |0.30| ± 0.12). These findings suggest that inter- and intra-run changes in gait complexity should be interpreted in the context of course elevation profiles before conclusions on human health are drawn.

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.

Using dynamic ultrasound to assess Achilles tendon mechanics during running: The effect on running pattern and muscle-tendon junction tracking

Achilles tendon strain can be quantified using dynamic ultrasound, but its use in running is limited. Minimal effects on running pattern and acceptable test-retest reliability of muscle-tendon junction (MTJ) tracking are prerequisites for ultrasound use during running. We aimed to assess (i) the effect of wearing an ultrasound transducer on running pattern and (ii) the test-retest reliability of MTJ tracking during running. Sixteen long-distance runners (nine injury-free, seven with Achilles tendinopathy) ran at different speeds on an instrumented treadmill with a 10-camera system tracking skin-mounted retroreflective markers, first without and then with an ultrasound transducer attached to the lower leg to track the MTJ of the gastrocnemius medialis. Spatiotemporal parameters, joint kinematics and kinetics were compared between conditions using mixed ANOVAs and paired t-tests. MTJ tracking was performed manually twice by three raters in ten participants. Variability and standard error of measurement (SEM) quantified the inter- and intra-tester test-retest reliability. The running pattern was not affected by wearing the ultrasound transducer, except for significantly less knee flexion during midstance (1.6°) and midswing (2.9°) found when wearing the transducer. Inter-rater and intra-rater SEMs for MTJ tracking to assess the tendon strain (0.43%, and 0.56%, respectively) were about four times as low as between-group differences presented in literature. The minimal effects found on the running pattern and acceptable test-retest reliability indicates that dynamic ultrasound during running can be appropriately used to study Achilles tendon mechanics and thereby help improve our understanding of Achilles tendon behavior during running, injury development and recovery.

Acute effects of the short-foot exercise in runners with medial tibial stress syndrome: A quasi-experimental study

OBJECTIVES

Analyze whether there are immediate changes in peak soleus activation and peak hindfoot eversion after short-foot exercise (SFE) in runners with medial tibial stress syndrome (MTSS). Secondarily, establish differences in peak soleus activation and peak hindfoot eversion between asymptomatic individuals and those presenting MTSS.

DESIGN

Quasi-experimental study.

SETTING

University Laboratory.

PARTICIPANTS

Thirty-two runners participated: 16 with MTSS and 16 in the no-pain group (NPG).

MAIN OUTCOME MEASURES

Soleus activation was measured using electromyography, and hindfoot eversion via 3D kinematic analysis. Participants performed SFE, and running data were collected at 9,12 and 15 km/h pre- and post-intervention.

RESULTS

SFE reduced peak soleus activation at 9 (p = 0.017) and 15 km/h (p = 0.019) for the MTSS group and at 15 km/h (p < 0.001) for the NPG, suggesting improved neuromuscular efficiency and potentially reduced tibial stress. SFE did not significantly affect peak hindfoot eversion. Significant correlations were found between ankle dorsiflexion range of motion and muscle activation (r = 0.585 to 0.849, p < 0.05). These findings suggest SFE could improve neuromuscular efficiency and reduce tibial stress, and highlights ankle flexibility's role in muscle activation.

CONCLUSIONS

SFE significantly reduces soleus activation, potentially improving neuromuscular efficiency and decreasing tibial stress.

MiRNA Expression in Long-Distance Runners with Musculoskeletal Pain: Implications for Pain Pathophysiology

Background: miRNAs are short, non-coding RNAs whose deregulation has been shown in painful processes, including musculoskeletal pain. This condition, which causes disability, impacts quality of life, and contributes to substantial healthcare costs, is also a critical issue in sports. In this case-control study, we evaluated the expression of four miRNAs involved in inflammation in runners with musculoskeletal pain and elucidated their functions and pathophysiological implications. Methods: A total of 17 runners with musculoskeletal pain and 17 age- and sex-matched runners without pain participated in this study. The levels of the miRNAs were evaluated by qRT-PCR. Bioinformatic tools were employed to identify the target genes and biological processes regulated by these miRNAs. Results: Compared to the controls, the runners with musculoskeletal pain exhibited significantly higher plasma levels of miR-133b (p = 0.02), miR-155-5p (p = 0.003) and let-7a-5p (p = 0.02). Multivariable regression analysis indicated that these three miRNAs exhibit a positive correlation (p < 0.05) with the presence of musculoskeletal pain, adjusted for age. Bioinformatic analysis suggested that the miRNAs hub genes are involved in regulatory processes, neuroinflammatory pathways, and human diseases that are associated with pain pathology. Conclusions: These results enhance our understanding of the potential role of miR-133b, miR-155-5p and let-7a-5p in pain-associated biological processes. The miRNA-mediated negative regulation of genes identified could explain the inflammatory and tissue repair processes in this population. Further studies are needed to confirm and validate the role of these miRNAs in painful conditions, especially considering the significant public health implications of managing inflammatory pain in sports.

Can Foot Orthoses Benefit Symptomatic Runners? Mechanistic and Clinical Insights Through a Scoping Review

BACKGROUND

Running is a widely practiced sport worldwide associated with a host of benefits on cardiovascular, metabolic, musculoskeletal, and mental health, but often leads to musculoskeletal overuse injuries. The prescription of a foot orthosis (FO) is common to manage musculoskeletal impairments during physical activity or functional tasks. Although FOs are frequently prescribed by clinicians for symptomatic populations of runners, the existing literature supporting the prescription of FOs in runners has predominantly focused on either uninjured individuals or a mix of uninjured and symptomatic populations. Thus, the effects of FOs on the treatment and/or prevention of overuse running injuries need to be investigated to guide future research and assist clinicians in their decision-making process.

MAIN BODY

This scoping review aimed to evaluate the immediate and long-term effects of FOs on lower limb biomechanics, neuromuscular parameters, and pain and disability in symptomatic runners, and to identify factors that may influence the effects of FOs. Five databases (CINAHL, SPORTDiscus, MEDLINE, Embase, and Web of Science) were searched, resulting in 2536 studies. A total of 30 studies, published between 1992 and 2023 (730 symptomatic runners), were included following the removal of duplicates and the screening process. Wearing FOs while running is related to an immediate and a long-term decrease in pain and symptoms of overuse running injuries. Also, wearing FOs while running decreases eversion at the foot/ankle complex, leads to a more lateral plantar pressure at the heel and forefoot, and may change running motor control strategies. Finally, the effectiveness of FOs is influenced by its added features.

CONCLUSIONS

This study provides recommendations for future research such as the need for standardized methods in describing FOs, considering participant characteristics such as foot morphology, and comparing different types of FOs. Also, this scoping review provides valuable insights for guiding the prescription and design of FOs, and suggests that integrating FOs into a comprehensive treatment plan may yield better results than standalone first-line treatments. Nonetheless, this scoping review highlights the need for future research to explore the optimal integration of FOs into injury-specific treatment plans.

Lateral Femoral Condyle Stress Fracture in an Ultramarathoner: A Case Report

CASE

A 62-year-old ultramarathon athlete presented to the clinic with right posterolateral knee pain for 3 to 4 weeks and muscle tightness. Magnetic resonance imaging demonstrated a right lateral femoral condyle fracture. The fracture was treated conservatively, with return full Ironman competition 14 months later.

CONCLUSION

Femoral condyle fractures should be suspected in endurance athletes with nonspecific knee pain to prevent further injury. These fractures are rare, and more studies are needed to determine risk factors, risk classification, and optimal treatment protocol. With rising popularity of ultraendurance events, sports medicine physicians must educate patients on injury recognition and mitigation strategies.

Comparison of Weekly Training Load and Acute: Chronic Workload Ratio Methods to Estimate Change in Training Load in Running

CONTEXT

Before examining the impact of training load on injury risk in runners, it is important to gain insight into the differences between methods that are used to measure change in training load.

OBJECTIVE

To investigate differences between 4 methods when calculating change in training load: (1) weekly training load; (2) acute : chronic workload ratio (ACWR), coupled rolling average (RA); (3) ACWR, uncoupled RA; (4) ACWR, exponentially weighted moving average (EWMA).

DESIGN

Descriptive epidemiology study.

SETTING

This study is part of a randomized controlled trial on running injury prevention among recreational runners. Runners received a baseline questionnaire and a request to share global positioning system training data.

PATIENTS OR OTHER PARTICIPANTS

Runners who registered for running events (distances 10-42.195 km) in the Netherlands.

MAIN OUTCOME MEASURE(S)

The primary outcome measure was the predefined significant increase in training load (weekly training loads ≥ 30% progression and ACWRs ≥ 1.5), based on training distance. Proportional Venn diagrams visualized the differences between the methods.

RESULTS

A total of 430 participants (73.3% men; mean age = 44.3 ± 12.2 years) shared their global positioning system training data for a total of 22 839 training sessions. For the weekly training load, coupled RA, uncoupled RA, and EWMA method, respectively, 33.4% (95% CI = 32.8, 34.0), 16.2% (95% CI = 15.7, 16.6), 25.8% (95% CI = 25.3, 26.4), and 18.9% (95% CI = 18.4, 19.4) of the training sessions were classified as significant increases in training load. Of the training sessions with significant increases in training load, 43.0% from the weekly training load method were different than the coupled RA and EWMA methods. Training sessions with significant increases in training load based on the coupled RA method showed 100% overlap with the uncoupled RA and EWMA methods.

CONCLUSIONS

The difference in the change in training load measured by weekly training load and ACWR methods was high. To validate an appropriate measure of change in training load in runners, future research on the association between training loads and running-related injury risk is needed.

The Impact of Blood Flow Restriction Training on Tibial Bone Stress Injury Rehabilitation: An Exploratory Case Series

Background

Lower extremity bone stress injuries (BSI) are common injuries among athletes and military members. Typical management involves a period of restricted weightbearing which can have rapid detrimental effects upon both muscle and bone physiology. Few studies have investigated the effect of blood flow restriction (BFR) training on bone in the rehabilitative setting.

Purpose

The purpose of this study was to investigate the effects of lower extremity exercise with the addition of BFR upon bone mineral density, bone mineral content, and lean body mass in military members with tibial BSIs.

Study Design

Case series.

Methods

Twenty military members with MRI-confirmed tibial BSI were recruited to complete lower extremity exercise with the addition of BFR twice per week for four weeks. The BFR cuff was applied proximally to the participant's involved limb while they performed gluteal, thigh, and leg resistance exercises. Outcomes were assessed at baseline and four weeks. The primary outcomes were whole leg bone mineral density (BMD), bone mineral content (BMC), and lean body mass (LM) as measured by dual-energy x-ray absorptiometry. Secondary outcomes included thigh and leg circumference measures and patient-reported outcomes, including the Lower Extremity Functional Scale (LEFS), Patient-Reported Outcomes Measurement Information System 57 (PROMIS-57), and Global Rating of Change (GROC).

Results

No significant differences were found in BMD (p=0.720) or BMC (p=0.749) between limbs or within limbs over time. LM was generally less in the involved limb (p=0.019), however there were no significant differences between or within limbs over time (p=0.404). For thigh circumference, significant main effects were found for time (p=0.012) and limb (p=0.015), however there was no significant interaction effect (p=0.510). No significant differences were found for leg circumference (p=0.738). Participants showed significant mean changes in LEFS (15.15 points), PROMIS physical function (8.98 points), PROMIS social participation (7.60 points), PROMIS anxiety (3.26 points), and PROMIS pain interference (8.39 points) at four weeks.

Conclusion

The utilization of BFR in the early rehabilitative management of tibial BSI may help mitigate decrements in both bone and muscle tissue during periods of decreased physical loading.

Level of Evidence

4.

The Dogma of Running Injuries: Perceptions of Adolescent and Adult Runners

CONTEXT

Adults perceive certain factors to increase or decrease the risk of sustaining running-related injuries, but many of their perceptions are not supported by research. Little is known about the perceptions that adolescent runners hold. Investigating perceptions for adolescent runners is needed to assist in the development of future injury educational materials, as these resources may need to be tailored differently for adolescents and adults.

OBJECTIVE

To identify factors that adolescent runners perceive as risk or protective factors for running-related injuries and to compare these perceptions with those of adult runners.

DESIGN

Cross-sectional study.

SETTING

Online survey.

PATIENTS OR OTHER PARTICIPANTS

We surveyed 302 adolescent (164 females, 138 males; age = 16.0 ± 1.4 years [range, 12-19 years]) and 357 adult runners (197 women, 160 men; age = 40.7 ± 11.8 years [range, 20-77 years]).

MAIN OUTCOME MEASURE(S)

Participants completed a survey with questions about whether factors related to training habits, footwear, biomechanics, strength, stretching, or nutrition influence the risk of sustaining a running-related injury. If ≥75% of adolescents indicated that a factor increases or decreases the risk of sustaining an injury, we considered that factor to be a perceived risk or protective factor, respectively. We also performed Fisher's exact test to compare the proportion of adolescent and adult runners who responded with "increase," "decrease," "neither increase or decrease," or "I don't know" to each question.

RESULTS

Adolescent runners perceived training habits, footwear, biomechanics, strength, stretching, and nutrition to increase or decrease the risk of sustaining a running-related injury. A larger proportion of adolescents than adults perceived that more footwear cushioning and stretching decrease injury risk, but a smaller proportion perceived that overtraining increases injury risk and strength decreases injury risk.

CONCLUSIONS

Differences in perceptions exist between adolescent and adult runners, and future educational materials and research questions may need to be tailored for different running populations.

MRI and single-cell RNA sequence results reveal the influence of anterior talofibular ligament injury on osteochondral lesions of the talus

Anterior talofibular ligament injuries and osteochondral lesions of the talus present unique challenges to orthopedic surgeons. This study aimed to investigate the relevant relationship between them by analyzing the Magnetic resonance imaging (MRI) results of clinical patients and single-cell RNA sequence (scRNA seq) results of healthy talus cartilage to discuss the risk factors. Data from 164 patients from 2018 to 2023 was retrospectively analyzed. The correlation analysis between ATFL injury grade and the Hepple stage of OLT determined by MRI was performed. Publicly available single-cell RNA datasets were collected. Single-cell RNA datasets from five volunteers of healthy talus cartilage were analyzed. ATFL injury grade was relevant with the Hepple stage of OLT (P < 0.05). The results of multivariate logistic regression analysis showed that injured area was the independent influencing factor of the incidence rate and the severity of OLT (P < 0.05). The Hepple stage of OLT was relevant with AOFAS and VAS (P < 0.05). Single-cell RNA sequence results showed that among the 9 subtypes of chondrocytes, the interaction strength between HTC-A and HTC-B is the highest. Their physical interactions are mainly achieved through the CD99 signaling pathway, and factor interactions are mainly achieved through the ANGPTL signaling pathway. Anterior talofibular ligament injury may lead to osteochondral lesions of the talus. Early medical intervention should be carried out for ligament injuries to restore joint stability and avoid cartilage damage.

Immediate effect of the use of toe separators on dynamic balance and ankle range of motion: a pilot study

BACKGROUND AND OBJECTIVES

Injuries involving ankle stability and range of motion are among the most frequent in athletes and in the general population. In response, this study aimed to assess the immediate effects of toe separators on dynamic stability and ankle range of motion in healthy young individuals.

METHODS

Among the 68 eligible participants, 50 healthy and active subjects completed all trials. The impact of the intervention was evaluated using the Weight Bearing Lunge Test and Y-Test. The control condition performed the tests without toe separators, while the experimental condition performed the tests with toe separators. All participants performed both conditions with a wash-out period of at least 7 days between trials.

RESULTS

Statistical analysis revealed no significant differences in dynamic balance (p > 0.05) and range of motion (p > 0.05) between the two conditions. Additionally, no asymmetries were detected between the lower limbs in both tests (p > 0.05).

CONCLUSIONS

The results of this pilot study indicate that using toe separators does not have an immediate effect on ankle range of motion and dynamic balance in young, healthy individuals. Future research should consider evaluating intervention programs of longer duration and exploring different populations.

Predictive Value of the KOJI AWARENESS Self-Evaluation System for Running Injuries in Elite Male Long-Distance Runners: A Prospective Cohort Study

Background

The KOJI AWARENESS (KA) test is a practical self-evaluation tool that assesses body movements and may help develop individual conditioning plans to improve movement function. However, the association between preseason KA scores and in-season injury occurrence remains unexplored.

Purpose

To investigate whether the KA self-screening test score can predict running-related injuries in elite long-distance runners.

Study Design

Cohort study; Level of evidence, 2.

Methods

A total of 47 elite college male long-distance runners (age, 18-22 years) were enrolled in this study in June 2022. The participants underwent the KA self-screening test to assess preseason upper limb, core, and lower limb function. Running-related injuries with a training time loss of >3 weeks were tracked for 6 months during the season. The participants were divided into injury and noninjury groups, and between-group comparisons and receiver operating characteristic (ROC) curve analysis were used to determine the association between the KA scores and the injury incidence. Chi-square tests and risk ratios were calculated based on the cutoff value- and injury-based grouping.

Results

Among the runners, 10 (21.3%) sustained an injury. There were no significant differences in the demographic characteristics between the injury and noninjury groups. The injury group had significantly lower KA scores than the noninjury group (median, 44.5 [interquartile range, 43-46.8] vs median, 48 [interquartile range, 46-50], respectively; P = .009). The ROC curve analysis determined a cutoff value of 46.5 points (sensitivity, 73%; specificity, 63.6%), indicating that the KA scores exhibited a relatively high predictive value for running-related injuries (area under the ROC curve, 0.764 [95% CI, 0.600-0.930]). The risk ratio for group division based on the cutoff value was 2.590 (95% CI, 1.329-5.047).

Conclusion

These findings demonstrated that the KA test is an effective self-screening tool for predicting the risk of running-related injuries in elite male long-distance runners.

An Investigation Into the Measurement of Injury Severity in Running-Related Injury Research: A Scoping Review

Understanding injury severity is essential to inform injury prevention practice. The aims of this scoping review were to investigate how running-related injury (RRI) severity is measured, compare how it differs across studies, and examine whether it influences study outcomes (i.e., injury rates and risk factor identification). This scoping review was prospectively registered with Open Science Framework. A systematic electronic search was conducted using PubMed, Scopus, SPORTDiscuss, MEDLINE, and Web of Science databases. Included studies were published in English between January 1980 and December 2023, investigated RRIs in adult running populations, and included a measure of injury severity. Results were extracted and collated. Sixty-six studies were included. Two predominant primary criteria are used to define injury severity: the extent of the effect on running and/or the extent of the physical description. When secondary definition criteria are considered, 13 variations of injury severity measurement are used. Two approaches are used to grade injury severity: a categorization approach or a continuous numerical scale. Overall, the measurement of RRI severity is relatively inconsistent across studies. Less than half of studies report incidence rates per level of injury severity, while none report specific risk factors across levels, making it difficult to determine if the approach to measuring injury severity influences these study outcomes. This lack of information is possibly contributing to inconsistent rates of RRIs reported, and the lack of clarity on risk factors.

Current iliotibial band syndrome alters patterns of running coordination in male and female runners, but not their levels of coordination variability

The aim of the present study was to compare the coordination patterns and levels of coordination variability of healthy and injured runners with iliotibial band syndrome (ITBS). Sixty runners divided into four groups (15 healthy males, 15 healthy females, 15 males with ITBS and 15 females with ITBS) ran at a steady and freely chosen pace on an over-ground track, and their coordination patterns of the lower limbs were calculated during 10 running stances using the vector coding technique. Both male and female runners with ITBS showed a greater dominance of the pelvis segment and the anti-phase patterns in the frontal plane thigh-pelvis coupling (p = 0.001, η2 = 0.36). In addition, injured female runners showed a greater hip adduction dominance, whereas injured males presented a greater anti-phase pattern in the transverse plane-frontal plane hip coupling (p = 0.003, η2 = 0.08). The levels of coordination variability during running stance did not change between ITBS injured and healthy runners in any of the couplings. Currently injured runners with ITBS appeared to present altered coordination patterns on the hip couplings that were partly dependent on gender but did not lead to changes in the coordination variability levels.

Prevalence and Risk Factors for Musculoskeletal Pain when Running During Pregnancy: A Survey of 3102 Women

BACKGROUND

Musculoskeletal pain while running is a concern to women during pregnancy and can lead to running cessation. To support women who wish to run during pregnancy, it is essential to understand the sites, severities and personal risk factors associated with musculoskeletal pain.

OBJECTIVE

The aim was to investigate prevalence and risk factors for musculoskeletal pain when running during pregnancy.

METHODS

An online survey was completed by women who had a child in the past 5 years and ran prior to and during pregnancy. Pain frequency informed prevalence rates by body site, and logistic regression odds ratios (ORs) and 95% confidence intervals were calculated.

RESULTS

A total of 3102 women of 23 ethnicities from 25 countries completed the survey. Women were 22-52 years old when they gave birth and ran 2-129 km/week during the 0.5-35 years before the birth of their youngest child. Women ran significantly less distance and less often during pregnancy than before pregnancy. Most women (86%) experienced pain while running during pregnancy (59% pelvis/sacroiliac joint, 52% lower back, 51% abdomen, 44% breast, 40% hip). The highest prevalence of severe-to-worst pain was at the pelvis/sacroiliac joint (9%). Women at greatest risk of pain while running during pregnancy had a previous injury (OR = 3.44) or were older (OR = 1.04). Women with a previous child were less likely to experience breast pain (OR = 0.76) than those running during their first pregnancy.

CONCLUSION

Healthcare practices to reduce pain should focus on regions of greatest musculoskeletal change during pregnancy, specifically the pelvis, lower back and abdomen. Efforts to support women to run for longer throughout pregnancy should focus on pain at the pelvis and breasts.

Effectiveness of Percutaneous Needle Electrolysis to Reduce Pain in Tendinopathies: A Systematic Review With Meta-Analysis

CONTEXT

Tendon injuries are common disorders in both workers and athletes, potentially impacting performance in both conditions. This is why the search for effective treatments is continuing.

OBJECTIVE(S)

The objective of this study was to analyze whether the ultrasound-guided percutaneous needle electrolysis technique may be considered a procedure to reduce pain caused by tendinosis.

EVIDENCE ACQUISITION

The search strategy included the PubMed, SCOPUS, CINAHL, Physiotherapy Evidence Database, SciELO, and ScienceDirect up to the date of February 25, 2024. Randomized clinical trials that assessed pain caused by tendinosis using the Visual Analog Scale and Numeric Rating Scale were included. The studies were evaluated for quality using the Cochrane Risk of Bias 2, and the evidence strength was assessed by the GRADEpro GDT.

EVIDENCE SYNTHESIS

Out of the 534 studies found, 8 were included in the review. A random-effects meta-analysis and standardized mean differences (SMD) were conducted. The ultrasound-guided percutaneous needle electrolysis proved to be effective in reducing pain caused by tendinosis in the overall outcome (SMD = -0.97; 95% CI, -1.26 to -0.68; I2 = 58%; low certainty of evidence) and in the short-term (SMD = -0.83, 95% CI, -1.29 to -0.38; I2 = 65%; low certainty of evidence), midterm (SMD = -1.28; 95% CI, -1.65 to -0.91; I2 = 0%; moderate certainty of evidence), and long-term (SMD = -0.94; 95% CI, -1.62 to -0.26; I2 = 71%; low certainty of evidence) subgroups.

CONCLUSION(S)

The application of the ultrasound-guided percutaneous needle electrolysis technique for reducing pain caused by tendinosis appears to be effective. However, due to the heterogeneity found (partially explained), more studies are needed to define the appropriate dosimetry, specific populations that may benefit more from the technique, and possible adverse events.

Do we underestimate the frequency of ankle sprains in running? A systematic review and meta-analysis

OBJECTIVE

To provide a systematic review and meta-analysis of the proportion of ankle sprains in running practices.

DESIGN

Systematic review and meta-analysis.

MAIN OUTCOME MEASURES

We calculated the weighted summary proportion and conducted meta-analyses for runners, considering levels (elite/recreational) and disciplines (distance, track, cross-country, trail, and orienteering).

RESULTS

32 studies were included in the systematic review and 19 were included in the meta-analysis with a level of quality ranging from poor to good. Proportion of ankle sprains in runners was 13.69% (95%CI = 7.40-21.54; I2 = 98.58%) in global, 12.20% (95%CI = 5.24-21.53; I2 = 89.31%) in elite, 19.40% (95%CI = 10.05-30.90; I2 = 99.09%) in recreational, 8.51% (95%CI = 4.22-14.12; I2 = 96.15%) in distance, 67.42% (95%CI = 0.50-82.85; I2 = 99.36%) in track, 27.07% (95%CI = 12.48-44.81; I2 = 97.97%) in cross-country, and 25.70% (95%CI = 19.87-32.14; I2 = 0.00) in orienteering.

CONCLUSIONS

Running practice results in significant proportion rate of ankle sprains. Recreational runners exhibit higher proportion than elite. Running disciplines, especially track, cross-country, and orienteering, influence reported ankle sprain rates, surpassing those of distance runners.

Evaluating Compliance With the Ottawa Rules: A Retrospective Clinical Audit at a District General Hospital in the UK

BACKGROUND

The Ottawa Rules are clinical decision tools designed to assist healthcare providers in determining the need for radiographs in patients with ankle or knee injuries. Compliance with these rules can lead to more efficient use of resources and reduced radiation exposure.

OBJECTIVE

This retrospective clinical audit aimed to evaluate healthcare provider's compliance with the Ottawa Rules in an Emergency Department setting and assess the positivity rates of requested knee and ankle X-rays.

METHODS

A two-cycle retrospective audit was conducted at Lincoln County Hospital's Emergency Department, involving 648 X-rays collected in two cycles. In between, multiple interventions were implemented to improve the outcomes.

RESULTS

The study revealed varying levels of compliance with the Ottawa Rules, with higher compliance observed for knee X-rays than ankle X-rays. The compliance for knee X-rays improved from 74.6% to 89.9% and ankle X-rays improved from 33.1% to 75.8%. Positivity rates for ankle radiographs were higher than knee radiographs in both cycles. The interventions implemented between the cycles significantly improved compliance rates with the Ottawa Rules.

CONCLUSION

The findings underscore the importance of adherence to the Ottawa Rules in optimizing patient care and resource utilization. The study suggests the need for continued education and periodic audits to maintain and further improve compliance rates. Additionally, the higher positivity rates for ankle radiographs highlight the importance of targeted imaging strategies based on clinical guidelines.

Enhancing running injury prevention strategies with real-time biofeedback: A systematic review and meta-analysis

The number of runners and the incidence of running-related injuries (RRIs) are on the rise. Real-time biofeedback gait retraining offers a promising approach to RRIs prevention. However, due to the diversity in study designs and reported outcomes, there remains uncertainty regarding the efficacy of different forms of feedback on running gait biomechanics. Three databases: MEDLINE, PUBMED, and SPORTDiscus were searched to identify relevant studies published up to March 2024, yielding 4646 articles for review. The quality of the included studies was assessed using the Downs and Black Quality checklist. Primary outcomes, including Peak Tibial Acceleration (PTA), Vertical Average Loading Rate (VALR), and Vertical Instantaneous Loading Rate (VILR), were analysed through meta-analysis. 24 studies met the inclusion criteria and were analysed in this review.17 used visual biofeedback (VB) while 14 chose auditory biofeedback (AB). The meta-analysis revealed a reduction in loading variables both immediately following the intervention and after extended training, with both visual and auditory feedback. Notably, the decrease in loading variables was more pronounced post-training and VB proved to be more effective than AB. Real-time biofeedback interventions are effective in lowering loading variables associated with RRIs. The impact is more substantial with sustained training, and VB outperforms AB in terms of effectiveness.

Demographics, culture and participatory nature of multi-marathoning-An observational study highlighting issues with recommendations

OBJECTIVES

The defining achievement of a multi-marathoner is completing 100 marathons. This study aimed to comprehensively document the phenomenon of multi-marathoning, addressing its demographics, culture and participatory nature, filling a gap in peer-reviewed research on the topic. Additionally, it aimed to provide recommendations for multi-marathon governing bodies, event organisers, health professionals and participants to address identified issues.

METHODS

A global survey was distributed to participants and individuals interested in multi-marathoning. It was distributed with support from major national and international multi-marathon clubs through their social media channels, email groups and newsletters. The survey was conducted anonymously and online.

RESULTS

The survey garnered responses from 830 participants across 40 countries, with an average marathon completion count of 146.54 (SD 201.83) per respondent. Gender distribution showed 60.69% men, 39.3% women and 0.1% gender variant/non-conforming. Respondents' average ages were 51.6 (SD 9.96) years for men, 48.83 (SD 9.15) years for women and 35.00 (SD 8.76) years for gender variant/non-conforming. As participants age, social and travel motivations surpass competitiveness. A majority (57%) of respondents had at least one contravention to the pre-participation screening questionnaire PARQ-+ and 67% reported taking pain relief medication around events. Notably, 93% of respondents reported multi-marathoning as beneficial for their mental health.

DISCUSSION

Multi-marathoning accommodates older athletes, but a significant gender imbalance exists in participation levels. Long-term health implications warrant attention from governing bodies, event organisers, health professionals and participants alike. Multi-marathoners should seek medical advice before participation, utilise modern equipment for health monitoring and optimise training accordingly.

CONCLUSION

Recommendations include encouraging diversity at events, ensuring event directors have well-resourced health plans and promoting participants' proactive health management before and during their involvement in the sport. This study not only advances our understanding of multi-marathoning as a sport but also contributes to theoretical frameworks such as SDT and HBM.

Prevalence of Sonographic Achilles Tendon, Patellar Tendon, and Plantar Fascia Abnormalities in Division I Collegiate Athletes From a Variety of Sports

OBJECTIVE

This study aimed to determine the prevalence of ultrasound abnormalities in the Achilles tendon, patellar tendon, and plantar fascia among a large cohort of collegiate student-athletes.

DESIGN

Observational cross-sectional study.

SETTING

Three Division I institutions.

PARTICIPANTS

243 student-athletes participated in this study. Exclusion criteria included those younger than 18 years or who underwent prior surgery/amputation of structures, including anterior cruciate ligament (ACL) surgeries with patellar tendon grafts.

INTERVENTIONS

Ultrasound examination of the Achilles tendon, patellar tendon, and plantar fascia of each leg was performed. An experienced sonographer reviewed each tendon video in a blinded manner, with a separate experienced sonographer separately reviewing to establish inter-rater reliability.

MAIN OUTCOME MEASURES

The primary outcome measured was the presence of any sonographic abnormality including hypoechogenicity, thickening, or neovascularity.

RESULTS

Ultrasound abnormalities were identified in 10.1%, 37.2%, and 3.9% of all Achilles tendons, patellar tendons, and plantar fasciae, respectively. Abnormalities were significantly associated with the presence of concurrent pain for all structures ( P < 0.01). Specifically, athletes with sonographic abnormalities were approximately 4 times [relative risk (RR) = 4.25; 95% confidence interval (CI), 2.05-8.84], 6 times (RR = 5.69; 95% CI, 2.31-14.00), and 5 times (RR = 5.17; 95% CI, 1.76-15.25) more likely to self-report pain in the Achilles tendon, patellar tendon, and plantar fascia, respectively.

CONCLUSIONS

This multi-institutional study completed at 3 Division I institutions is the largest study of its kind to identify the prevalence of sonographic abnormalities in the Achilles tendon, patellar tendon, and plantar fascia among collegiate student-athletes of various sports.

Do Exercise-Based Prevention Programs Reduce Injury in Endurance Runners? A Systematic Review and Meta-Analysis

BACKGROUND

Endurance running is a popular sport and recreational activity yet is associated with a high prevalence of injury. Running related injuries (RRIs) are a leading cause of drop-out and represent a substantial financial burden to runners and healthcare services. There is clear evidence for the use of exercise-based injury prevention programs in games-based and youth sport settings, yet the research investigating the use of exercise to reduce injury risk in endurance runners has not been adequately reviewed recently.

OBJECTIVES

The aim of this review and meta-analysis was to systematically summarize the current research that has investigated the effect of exercise-based prevention programs and their state of supervision on the risk of RRIs in endurance runners.

METHODS

Three databases were searched for relevant studies. Selection and review were completed by two independent reviewers using the following inclusion criteria: (1) study population used endurance running training for health, occupational, or performance outcome(s); (2) participants performed running as their main form of exercise (> 50% of their total training time); (3) study was a randomized controlled trial; (4) a non-running-based exercise intervention was used; (5) a running-only or placebo exercise control group was included; (6) injury rate or incidence was reported; (7) injuries were recorded prospectively alongside the exercise training. Two meta-analyses were conducted using random-effects models, one based on log risk ratio and one based on log incidence rate ratio. The Cochrane Risk of Bias Assessment Tool 2 was used to evaluate the quality of studies and the Grading of Recommendations Assessment, Development and Evaluations approach was employed to grade the certainty of evidence.

RESULTS

A total of nine articles containing 1904 participants were included in analysis. Overall pooled results showed no significant differences between intervention and control groups in injury risk (z = - 1.60; p = 0.110) and injury rate (z = - 0.98; p = 0.329), while a post hoc analysis evaluating supervised interventions only showed that injury risk was significantly lower in the intervention group compared to the control group (z = - 3.75, p < 0.001). Risk of bias assessment revealed that seven studies included in the analysis were of low quality.

CONCLUSIONS

Exercise-based interventions do not appear to reduce the risk and rate of running-related injuries. Supervision may be essential for exercise-based intervention programs to reduce risk of RRIs, possibly due to increased compliance. Studies with more robust designs that include supervised exercise interventions should be prioritized in the future.

TRIAL REGISTRY

Clinical Trial Registration: PROSPERO CRD42021211274.

The Effects of Lower Leg Compression Garments on Lower Extremity Sports Injuries, Subjective Fatigue and Biomechanical Variables: A Systematic Review with Meta-analysis

The objective of this study was to systematically review the literature on the effect of CGs versus non-CGs (such as regular socks) or versus placebo garments on 1) the incidence of lower extremity sports injuries and 2) subjective ratings of fatigue and biomechanical variables in athletes at participating in any sport that required any level of running performance, given that fatigue-related biomechanical alterations may increase the risk of sports injuries. This study was a systematic review with meta-analyses. PubMed, Embase, CINAHL, Cochrane, PEDro, and Scopus were searched for eligible studies until 7 July 2021. Two reviewers independently assessed the risk of bias using the Cochrane Collaboration's tool for risk of bias. Meta-analyses were performed using a random-effects model. The Grades of Recommendation, Assessment, Development and Evaluation (GRADE) approach was used to assess the certainty of evidence for all outcome measures. Twenty-three studies, all with a high risk of bias, were included. Nineteen studies were used in the meta-analyses. No studies focused on the effect of CGs on the incidence of lower extremity sports injuries in athletes. Seventeen studies investigated the effect of CGs on subjective ratings of fatigue, but meta-analysis showed no difference in effectiveness between CGs versus non-CGs (such as regular socks) and versus placebo CGs (low certainty evidence). Because of heterogeneity, pooling of the results was not possible for the biomechanical variables. Nonetheless, low certainty evidence showed no effect of CGs. We identified no evidence for a beneficial or detrimental effect of lower leg CGs on the occurrence of lower extremity sports injuries, subjective ratings of fatigue, or biomechanical variables in athletes at any level of running performance. Based on the variable use of running tests, definitions used for biomechanical variables, and reporting of CG characteristics and more standardized reporting is recommended for future studies evaluating CGs.

Immediate Effects of Instrument-Assisted Soft-Tissue Mobilization Versus Dry Needling on Trigger Point Pain and Tightness of Calf Muscles in Long-Distance Runners

Introduction Muscle tightness is frequently identified as a potential precursor to muscle injuries. Reclaiming flexibility and enhancing range of motion (ROM) is crucial for preventing injuries and achieving improvements in performance. The present study examines the immediate effects of instrument-assisted soft-tissue mobilization (IASTM) and dry needling (DN) in reducing trigger point pain and calf tightness in long-distance runners. Methodology A total of 40 long-distance runners were recruited in the study (30 males and 10 females). The procedure was performed under the author's surveillance at the sports complex. These recruited players were placed into two groups: the IASTM (n=20) and the DN (n=20) group. The outcome measures used were the pressure algometer for assessing pain pressure threshold and the lunge test. An iPhone Measure app (Measure app, Apple App Store 2023) is used to assess ankle dorsiflexion ROM. The evaluation took place both prior to and immediately following the intervention and 48 hours after the intervention. Result The analysis within each group revealed a significant alteration in pain pressure threshold for both the IASTM and DN groups (p≤0.05), along with a relative enhancement in ankle dorsiflexion ROM observed in the IASTM group (p≤0.05). Between-group analysis revealed a notable difference with an effect size difference of Cohen's d=1.06 (large difference) in pain pressure threshold, d=0.21 (small difference) in lunge test, and d=0.57 (medium difference) in ankle dorsiflexion ROM. Conclusion The present study concludes that both groups, IASTM and DN, showed significant effects in improving pain pressure threshold in long-distance runners. However, DN showed better results. IASTM showed significant results in enhancing the ankle dorsiflexion ROM immediately. This implies that it can be used in conjunction with stretching to decrease pain and enhance flexibility, hence improving performance and preventing injuries.

Return to Play in the Professional Athlete

The management of any injury in elite athletes poses unique challenges distinct from the general population because the goal is rapid recovery and return to play (RTP) while simultaneously managing residual symptoms and minimizing risk of reinjury. The time required for treatment, recovery, and return to peak performance can have consequences for both the athlete and his or her team: financial implications, psychological stressors, team dynamics, and future performance. RTP after an injury in the professional athlete requires a complex decision-making process with many stakeholders. Several factors influence this decision, not the least of which is the type and mechanism of injury. This article provides an overview of the RTP process including nonmedical factors that may influence this decision, common injuries seen in professional athletes, injury patterns particular to certain popular sports, and imaging guidelines for such injuries.

Pain and disability were related to Y-balance test but not with proprioception acuity and single-leg triple-hop test in patients with patellofemoral pain: A cross-sectional study

INTRODUCTION

Patellofemoral pain is a common complaint between physically active subjects. Patients with patellofemoral pain present limitations to performing daily activities. Pain could alter proprioceptive acuity and lead to movement impairment. The aim of this study was to investigate the relationship of pain and disability with proprioception acuity and physical performance in patients with patellofemoral pain.

METHODS

Forty-eight patients with patellofemoral pain [age 31.15 (5.91) years; 30 (62.50%) males] were recruited. Data collected included pain intensity, pain duration, disability, joint position sense (JPS) test at 20° and 60° of knee flexion, and physical performance tests (Single-Leg Triple-Hop Test and Y- Balance Test). Spearman's rank correlation coefficient (rs) and 95% confidence intervals (CI) were computed to assess the relationship between the variables.

RESULTS

Pain intensity was correlated with Y-Balance Test posteromedial component (rs = -0.32, 95%CI = -0.55 to -0.03, p = 0.029) and the composite score (rs = -0.35, 95%CI = -0.58, -0.07, p = 0.015). Pain duration was correlated with Y-Balance Test posterolateral component (rs = -0.23, 95% CI = -0.53 to -0.01, p = 0.047). Disability was correlated with Y-Balance Test posteromedial component (rs = 0.41, 95% CI = 0.14 to 0.62, p = 0.004). Pain and disability were not correlated with JPS and the Single-Leg Triple-Hop Test.

CONCLUSION

Pain and disability were related to Y-Balance Test but not to proprioceptive acuity and Single-Leg Triple-Hop Test in patients with patellofemoral pain.

Diffusion tensor imaging combined with chemical shift-encoded sequence to quantify the adaptive changes of calf muscles in amateur marathoners

PURPOSE

Calf muscles play an important role in marathon race, and the incidence of injury is high in this process. This study prospectively quantified diffusion tensor metrics, muscle fat fraction (MFF) and cross-sectional area (CSA) of calf muscles induced by endurance exercise in amateur marathoners, and the potential mechanisms underlying the changes in these parameters were analyzed.

METHOD

In this prospective study, 35 marathoners (27 males, 8 females; mean age (standard deviation, SD), 38.92 (4.83) years) and 26 controls (18 males, 8 females; mean age (SD), 38.35 (6.75) years) underwent magnetic resonance imaging (MRI) from September 2022 to March 2023. The diffusion tensor eigenvalues (λ1, λ2, λ3), radial diffusivity (RD), fractional anisotropy (FA), MFF and CSA of calf muscles were compared between marathoners and controls. A binary logistic regression model with gender correction was performed analyze the relationship between marathon exercise and DTI parameters, CSA and MFF of calf muscles.

RESULTS

Interobserver agreement was good (κ = 0.71). The results of binary logistic regression model with gender correction showed that the regression coefficients of FA values in anterior group of calf (AC), soleus (SOL), medial gastrocnemius (MG) and lateral gastrocnemius (LG) were negative, and the odds ratios (OR) were 0.33, 0.45, 0.35, 0.05, respectively (P < 0.05). The OR of RD in SOL and λ2 in external group of calf (EC) were relatively higher, 3.74 and 3.26, respectively (P < 0.05). CSA was greater in SOL of marathoners, with an OR value of 1.00(P < 0.05). The MFF in AC and LG was lower in marathoners and OR of two indexes were -0.69 and -0.59, respectively (P < 0.05).

CONCLUSIONS

Diffusion tensor imaging (DTI) combined with chemical shift-encoded sequence can noninvasively detect and quantify the adaptive changes of calf muscle morphology, microstructure and tissue composition induced by long-term running training in amateur marathoners.

Injury patterns and healthcare utilisation by runners of the New York City Marathon

Objectives

The purpose of this study was to describe injury patterns and healthcare utilisation of marathon runners.

Methods

This was a previously reported 16-week prospective observational study of runners training for the New York City Marathon. Runners completed a baseline survey including demographics, running experience and marathon goal. Injury surveys were collected every 4 weeks during training, as well as 1 week before and 1 week after the race. Injury details collected included anatomic location, diagnosis, onset, and treatment received.

Results

A total of 1049 runners were enrolled. Injuries were reported by 398 (38.4%) during training and 128 (14.1%) during the marathon. The overall prevalence of injury was 447/1049 (42.6%). Foot, knee and hip injuries were most common during training, whereas knee, thigh and foot injuries were most common during the race. The most frequent tissue type affected was the category of muscle, tendon/fascia and bursa. The prevalence of overuse injuries increased, while acute injuries remained constant throughout training. Hamstring injuries had the highest prevalence of diagnosis with 38/564 injuries (6.7%). Of the 447 runners who reported an injury, 224 (50.1%) received medical care. Physical therapy was the most common medical care received with 115/1037 (11.1%) runners during training and 44/907 (4.9%) postrace.

Conclusion

Runners training and participating in a marathon commonly experience injuries, especially of the foot and knee, which often are overuse soft tissue injuries. Half of the injured runners sought out medical care for their injury. Understanding the patterns of injuries affecting marathon runners could help guide future injury prevention efforts.

Clinical and exercise professional opinion of return-to-running readiness after childbirth: an international Delphi study and consensus statement

Female athletes have identified a lack of guidance as a barrier to successfully returning to running postpartum, and existing guidelines are vague. Our aim was to define the current practice of determining postpartum run-readiness through a consensus survey of international clinicians and exercise professionals in postpartum exercise to assist clinicians and inform sport policy changes.A three-round Delphi approach was used to gain international consensus from clinicians and exercise professionals on run-readiness postpartum. Professionals who work with postpartum runners participated in an online survey to answer open-ended questions about the following postpartum return-to-running topics: definitions (runner and postpartum), key biopsychosocial milestones that runners need to meet, recommended screening, timeline to initiate running, support items, education topics and factors that contribute to advising against running. Consensus was defined as ≥75% participant agreement.One hundred and eighteen professionals participated in round I, 107 participated in round II (response rate 90.6%) and 95 participated in round III (response rate 80.5%). Responses indicated that, following a minimum 3-week period of rest and recovery, an individualised timeline and gradual return to running progression can be considered. Screening for medical and psychological concerns, current physical capacity, and prior training history is recommended prior to a return to running.This study proposes recommendations for the initial guidance on return-to-running postpartum, framed in the context of current research and consensus from professionals. Future research is needed to strengthen and validate specific recommendations and develop guidelines for best practice when returning-to-running after childbirth.

Acute effects of negative heel shoes on perceived pain and knee biomechanical characteristics of runners with patellofemoral pain

BACKGROUND

To determine the effects of negative heel shoes on perceived pain and knee biomechanical characteristics of runners with patellofemoral pain (PFP) during running.

METHODS

Sixteen runners with PFP ran in negative (-11 mm drops) and positive (5 mm drops) heel shoes while visual analog scale (VAS) scores, retroreflective markers, and ground reaction force were acquired by applying a 10-cm VAS, infrared motion capture system, and a three-dimensional force plate. Knee moment, patellofemoral joint stress (PFJS), and other biomechanical parameters during the stance phase were calculated based on inverse dynamics and a biomechanical model of the patellofemoral joint.

RESULTS

The foot inclination angle, peak PFJS during the stance phase, patellofemoral joint reaction force, knee extension moment, and quadriceps force at the time of peak PFJS of runners with PFP in negative heel shoes were lower than that in positive heel shoes, no significant difference was found in VAS scores, knee flexion angle, patellofemoral contact area, and quadriceps moment arm at the time of peak PFJS.

CONCLUSIONS

Compared to positive heel shoes, running in negative heel shoes decreases peak PFJS in runners with PFP, which may decrease patellofemoral joint loading, thus reducing the possibility of further development of PFP.

TRAIL REGISTRATION

Sports Science Experiment Ethics Committee of Beijing Sport University. 2023095H, April 18, 2023 (prospectively registered).

Biomechanical Effect on Jack's Test on Barefoot Position, Regular Socks, and Biomechanics Socks

The proper dorsal flexion movement of the first metatarsophalangeal joint (MTPJ) is crucial for an accurate gait. Restricted movement can disrupt the windlass mechanism, and Jack's test is a tool to assess such alterations. Although running socks are commonly used, their influence on the windlass mechanism remains unclear. Therefore, the aim of this study was to measure the resistance to passive dorsal flexion of the first metatarsophalangeal joint (MTPJ) under three different conditions: barefoot, wearing regular socks, and wearing biomechanical socks, using a digital force gauge.

METHODS

The research involved a sample size of 30 subjects (14 men and 16 women), and Jack's test was conducted using a digital force gauge and a lever system. Three conditions were measured, barefoot, with a regular sock, and with the biomechanical socks.

RESULTS

Statistically significant differences were observed when using biomechanical socks with orthopedic corrections during Jack's test, as measured with the digital force gauge (13.33 N ± 3.54, p < 0.001).

CONCLUSIONS

The utilization of biomechanical socks with a kinetic wedge, reinforced mesh in the medial longitudinal arch, and padding in the heel area results in a reduction of the force required, measured in newtons, to perform dorsal flexion of the first metatarsophalangeal joint (MTPJ) during Jack's test compared to being barefoot or wearing regular socks.

Exercise-induced Musclin determines the fate of fibro-adipogenic progenitors to control muscle homeostasis

The effects of exercise on fibro-adipogenic progenitors (FAPs) are unclear, and the direct molecular link is still unknown. In this study, we reveal that exercise reduces the frequency of FAPs and attenuates collagen deposition and adipose formation in injured or disused muscles through Musclin. Mechanistically, Musclin inhibits FAP proliferation and promotes apoptosis in FAPs by upregulating FILIP1L. Chromatin immunoprecipitation (ChIP)-qPCR confirms that FoxO3a is the transcription factor of FILIP1L. In addition, the Musclin/FILIP1L pathway facilitates the phagocytosis of apoptotic FAPs by macrophages through downregulating the expression of CD47. Genetic ablation of FILIP1L in FAPs abolishes the effects of exercise or Musclin on FAPs and the benefits on the reduction of fibrosis and fatty infiltration. Overall, exercise forms a microenvironment of myokines in muscle and prevents the abnormal accumulation of FAPs in a Musclin/FILIP1L-dependent manner. The administration of exogenous Musclin exerts a therapeutic effect, demonstrating a potential therapeutic approach for muscle atrophy or acute muscle injury.

A One Session Gait Retraining Protocol with Metronome Augmentation Increases Cadence in Novice and Recreational Runners

Background

Running is a common leisure physical activity that carries a risk for running related injury (RRI). Non-experienced runners are more likely to sustain RRIs. One form of gait retraining focuses on increasing cadence to improve running biomechanics related to RRI. Protocols for increasing cadence must be pragmatic to be implemented into clinical practice.

Hypothesis/Purpose

The purpose of this study was to determine if a pragmatic protocol including one instructional session, followed by independent gait retraining with metronome augmentation resulted in increased cadence and altered biomechanics in novice and recreational runners.

Study Design

Randomized Controlled Trial.

Methods

Thirty-three novice or recreational adult runners completed a 12 Minute Cooper Run on an indoor track. Variables measured during the 12 Minute Cooper Run included distance, rate of perceived exertion (RPE), heart rate (HR), and 3-D biomechanics using inertial measurement units (IMUs). After baseline testing, the intervention group received instruction and five minutes of gait retraining at a cadence set 5-10% higher than baseline with metronome augmentation (Pro Metronome- Tempo, Beat; by Xiao Yixiang). They then ran two to three times a week for two weeks up to 30 minutes per session with the metronome set at the new cadence. After two weeks, repeat testing using the same protocol was completed. A Mann-Whitney U test analyzed differences between groups.

Results

Cadence at one minute (p = 0.037) and average cadence over the entire run (p=0.002) increased in the intervention group only with a large effect size (Cohens d = 0.837). No other group differences were found.

Conclusion

A pragmatic gait retraining protocol with metronome augmentation including one instructional and four to six independent sessions over a two-week duration increased cadence without negative effects on HR, RPE, distance. Biomechanics did not change with this intervention. Further research with pragmatic gait retraining protocols that increase cadence are needed with larger sample sizes, repeated measures over time, across runners of various abilities and experience levels.

Level of Evidence

Level 2.

Effects of a 12-week gait retraining program on the Achilles tendon adaptation of habitually shod runners

PURPOSE

This study investigated the effects of a 12-week gait retraining program on the morphological and mechanical properties of the Achilles tendon (AT) during running on the basis of real-time dynamic ultrasound imaging.

METHODS

A total of 30 male recreational runners who were used to wearing cushioned shoes with a rearfoot strike (RFS) pattern were recruited. They were randomized into a retraining group (RG, n = 15) and a control group (CG, n = 15). The RG group was asked to run in five-fingered minimalist shoes with a forefoot strike (FFS) pattern, and the CG group was asked to keep their strike pattern. Three training sessions were performed per week. All the participants in RG uploaded running tracks obtained through a mobile application (.jpg) after each session for training supervision. The ground reaction force, kinematics, and kinetics of the ankle joint at 10 km/h were collected using an instrumented split-belt treadmill and a motion capture system. The morphological (length and cross-sectional area) and mechanical characteristics (force, stress, strain, etc.) of AT in vivo were recorded and calculated with a synchronous ultrasonic imaging instrument before and after the intervention. Repeated two-way ANOVA was used to compare the aforementioned parameters.

RESULTS

A total of 28 participants completed the training. The strike angle of RG after training was significantly smaller than that before training and significantly smaller than that of CG after training (F (1, 13)  = 23.068, p < 0.001, partial η2  = 0.640). The length (F (1, 13)  = 10.086, p = 0.007, partial η2  = 0.437) and CSA (F (1, 13)  = 7.475, p = 0.017, partial η2  = 0.365) of AT in RG increased after training. A significant main effect for time was observed for the time-to-peak AT force (F (1, 13)  = 5.225, p = 0.040, partial η2  = 0.287), average (F (1, 13)  = 7.228, p = 0.019, partial η2  = 0.357), and peak AT loading rate (F (1, 13)  = 11.687, p = 0.005, partial η2  = 0.473).

CONCLUSION

Preliminary evidence indicated that a 12-week gait retraining program could exert a beneficial effect on AT. 57% (8/14) runners in RG shifted from RFS to FFS pattern. Although not all runners were categorized as FFS pattern after the intervention, their foot strike angle was reduced. Retraining primarily positively promoted AT morphological properties (i.e., CSA and length) to strengthen AT capability for mechanical loading.

Relevant Biomechanical Variables in Skateboarding: A Literature Review

Skateboarding, once regarded primarily as a means of transportation and entertainment for youth, has become a recognized professional sport, gaining global popularity. With its recent inclusion in the Olympics, a growing imperative exists to comprehensively understand biomechanics explaining skateboarding performance. This literature review seeks to consolidate knowledge within this domain, focusing on experimental and modeling studies about skateboard riding and tricks. The criteria for study selection encompassed content relevance and publication year, spanning from the last two decades and extending further back to 1980 following cross-referencing of seminal works. Peer-reviewed journal articles, conference proceedings, and books were considered, with comprehensive searches conducted on electronic databases, including SCOPUS, PubMed, Scielo, and Taylor & Francis. Comprehending the biomechanical facets of skateboarding is essential in promoting its use and ensuring safety among all practitioners. Insights into factors such as body kinetics, kinematics, and muscle activation represent a foundational step toward understanding the nuances of this sport with implications for both clinical and biomechanical research. Modern data collection systems such as inertial measurement units (IMU) and electromyography (EMG) offer unprecedented insights into human performance during skateboarding, such as joint range of motion, coordination, and muscle activation, whether in casual riding or executing complex tricks and maneuvers. Developing robust modeling approaches also holds promise for enhancing skateboarding training and performance. Crucially, these models can serve as the initial framework for understanding injury mechanisms and implementing strategies to improve performance and mitigate injury risks.