Collegiate Cross-country Runners Research Articles

Epidemiology of Bone-Stress Injuries and Health Care Use in Pac-12 Cross-Country Athletes.

Bone-stress injury (BSI) is common in collegiate athletes. Injury rates and health care use in running athletes are not well documented. To describe the rate and classification of injury and associated health care use in collegiate cross-country runners with BSI. Descriptive epidemiology study. Sports medicine facilities participating in the Pac-12 Health Analytics Program. Pac-12 Conference collegiate cross-country athletes. Counts of injury and health care resources used for each injury. Injury rates were calculated based on athlete-seasons. A total of 168 BSIs were reported over 4 seasons from 80 team-seasons (34 men's and 46 women's team-seasons) and 1220 athlete-seasons, resulting in 1764 athletic training services and 117 physician encounters. Bone-stress injuries represented 20% of all injuries reported by cross-country athletes. The average BSI rate was 0.14 per athlete-season. Injury rates were higher in female (0.16) than male (0.10) athletes and higher in the 2019-2020 season (0.20) than the 2020-2021 (0.14), 2018-2019 (0.12), and 2021-2022 (0.10) seasons. Most BSIs occurred in the lower leg (23.8%) and the foot (23.8%). The majority of injuries were classified as overuse and time loss (72.6%) and accounted for most of the athletic training services (75.3%) and physician encounters (72.6%). We found a mean of 10.89 athletic training services per overuse and time-loss injury and 12.20 athletic training services per overuse and non-time-loss injury. Mean occurrence was lower for physician encounters (0.70), prescription medications (0.04), tests (0.75), procedures (0.01), and surgery (0.02) than for athletic training services (10.50). Bone-stress injuries are common in collegiate cross-country runners and require considerable athletic training resources. Athletic trainers should be appropriately staffed for this population, and suspected BSIs should be confirmed with a medical diagnosis. Future investigators should track treatment codes associated with BSI to determine best-practice patterns.

A hierarchical clustering approach for examining the relationship between pelvis-proximal femur geometry and bone stress injury in runners

Bone stress injury (BSI) risk in runners is multifactorial and not well understood. Unsupervised machine learning approaches can potentially elucidate risk factors for BSI by identifying groups of similar runners within a population which differ in BSI incidence. Here, a hierarchical clustering approach is used to identify groups of collegiate cross country runners based on 2-dimensional frontal plane pelvis and proximal femur geometry, which was extracted from dual-energy X-ray absorptiometry scans and dimensionally reduced by principal component analysis. Seven distinct groups were identified using the cluster tree, with the initial split being highly related to female-male differences. Visual inspection revealed clear differences between groups in pelvis and proximal femur geometry, and groups were found to differ in lower body BSI incidence during the subsequent academic year (Rand index = 0.53; adjusted Rand index = 0.07). Linear models showed between-cluster differences in visually identified geometric measures. Geometric measures were aggregated into a pelvis shape factor based on trends with BSI incidence, and the resulting shape factor was significantly different between clusters (p < 0.001). Lower shape factor values, corresponding with lower pelvis height and ischial span, and greater iliac span and trochanteric span, appeared to be related to increased BSI incidence. This trend was dominated by the effect observed across clusters of male runners, indicating that geometric effects may be more relevant to BSI risk in males, or that other factors masked the relationship in females. More broadly, this work outlines a methodological approach for distilling complex geometric differences into simple metrics that relate to injury risk.

Pre-injury Knee and Ankle Mechanics During Running are Reduced Among Collegiate Runners who Develop Achilles Tendinopathy.

Achilles tendinopathies (AT) are common in runners, but prospective data assessing running mechanics associated with developing AT are limited. Asymmetry in running mechanics is also considered a risk factor for injury, though it is unknown if the problematic mechanics occur on the injured limb only or are present bilaterally. To prospectively identify differences in pre-injury running biomechanics in collegiate runners who did and did not develop AT and determine if between-limb asymmetries were associated with which limb developed AT. Running gait data were obtained pre-season on healthy collegiate cross country runners, and AT incidence was prospectively recorded each year. Spatiotemporal, ground reaction forces, and joint kinematics and kinetics were analyzed. Linear mixed effects models assessed differences in biomechanics between those who did and did not develop AT during the subsequent year. Generalized linear mixed effects models determined if the asymmetry direction was associated with which limb developed an AT, with odds ratios (OR) and 95% confidence intervals [95% CI] reported. Data from 106 runners were analyzed and 15 developed AT. Pre-injury biomechanics of runners who developed AT showed less peak knee flexion (non-injured: 45.9 degrees [45.2, 46.6], injured: 43.2 degrees [41.5, 44.9], p < 0.001), ankle dorsiflexion (non-injured: 28.7 degrees [28.0, 30.2], injured: 26.0 degrees [23.8, 28.3], p = 0.01), and knee extensor moment (non-injured: -2.18 Nm/kg [-2.24, -2.12], injured: -2.00 Nm/kg [-2.17, -1.84], p = 0.02). The limb demonstrating less peak knee flexion had a greater odds of sustaining an AT (OR = 1.29 [1.00, 1.65], p = 0.05). Knee and ankle kinematics, in addition to knee kinetics, were associated with developing an AT. Monitoring these mechanics may be useful for prospectively identifying runners at risk of developing AT.

Dynamic postural control in injured collegiate cross-country runners is not associated with running-related injury

BackgroundBiomechanical factors have been associated with running-related injury, but associations are unclear. Dynamic postural stability may be a factor related to injury that has not been studied extensively. Research questionDoes dynamic postural control differ in those with a history of running-related injury or those who go on to sustain a running-related injury? MethodsSixty-five (45 injured; 20 uninjured) and fifty-eight (13 injured; 45 uninjured) collegiate cross-country runners were available for our retrospective and prospective analyses. Time to stabilization and dynamic postural stability index were collected during two separate jump landing tasks (forward and lateral direction) for each leg. Retrospective injury was tabulated by a running history survey. Prospective injuries were recorded by a licensed athletic trainer during the competitive season. Differences in postural stability were compared between injured and uninjured groups and between limbs using two-way ANOVA’s. An overall group by leg comparison was completed for each task. ResultsThe non-dominant limb demonstrated better postural stability indices regardless of injury history. An interaction was observed between limbs and history of injury for the anterior-posterior time to stabilization for the lateral task. The non-dominant limb demonstrated better medio-lateral postural stability indices and time to stabilization during the lateral task, regardless of prospective injury. SignificanceDynamic postural stability was reduced in the dominant limb, but no clear differences were seen between injured and uninjured runners. This suggests dynamic postural stability may be altered in individuals with a history of a running-related injury, but no relationship to subsequent injury was substantiated. Further work is needed to understand how dynamic postural stability may be related to running-related injury.

Kinematic and muscle force asymmetry in healthy runners: How do different methods measure up?

BackgroundComparing the performance of one leg to another is a common means of assessing running gait to help inform clinical management strategies. Various methods are employed to quantify asymmetries between limbs. However, limited data is available describing the amount of asymmetry that may be expected during running and no index has been identified as preferable for making a clinical determination of asymmetry. Therefore, this study aimed to describe amounts of asymmetry in collegiate cross-country runners and compare different methods of calculating asymmetry. Research questionWhat can be expected as a normal amount of asymmetry in biomechanical variables in healthy runners when using different indices to quantify limb symmetry? MethodsSixty-three (29 male and 34 female) runners participated. Running mechanics were assessed during overground running using 3D motion capture and a musculoskeletal model using static optimization to estimate muscle forces. Independent t-tests were utilized to determine statistical differences in variables between legs. Different methods of quantifying asymmetry were then compared to statistical differences between limbs to determine cut-off values and the sensitivity and specificity of each method. ResultsA large portion of runners demonstrated asymmetry during running. Kinematic variables can be expected to have small differences (2–3 degrees) between limbs while muscle forces may show greater amounts of asymmetry. The sensitivities and specificities for each method of calculating asymmetry were similar, however, different methods led to different cut-off values for each variable investigated. SignificanceAsymmetry can be expected between limbs during running. However, when assessing asymmetry, practitioners should consider the joint, variable, and method of calculating asymmetry when determining differences between limbs.

Iron Status and Homeostasis Across 2 Competitive Seasons in NCAA Division I Collegiate Cross-Country Runners Residing at Low Altitude.

Inflammatory cytokines including interleukin-6 can upregulate hepcidin and decrease iron absorption. Endurance exercise is associated with transient increases in cytokines, which may alter the risk of iron deficiency (ID). This study examined whether chronic elevations in basal levels of cytokines and hepcidin were associated with ID in highly trained runners. Fifty-four collegiate runners (26 males and 28 females) living at ∼1625m were recruited from an NCAA Division I cross-country team for this prospective cohort study. Over 2 seasons, fasted, preexercise blood draws were performed in the morning 4 times per season and were analyzed for hemoglobin concentration, ferritin, soluble transferrin receptor (sTfR), hepcidin, and 10 cytokines. Stages of ID were defined using ferritin, sTfR, and hemoglobin concentration. During the study, a registered dietician provided all runners with iron supplements using athletic department-created guidelines. Fifty-seven percent of females and 35% of males exhibited stage 2 ID (ferritin <20ng/mL or sTfR >29.5nmol/L) at least once. Cytokines, ferritin, and sTfR exhibited changes through the 2years, but changes in cytokines were not associated with alterations in hepcidin, ferritin, or sTfR. In males and females, lower ferritin was associated with lower hepcidin (both P < .0001). One female exhibited higher hepcidin and lower iron stores compared with other individuals, suggesting a different etiology of ID. ID is common in highly trained collegiate runners. In general, the high prevalence of ID in this population is not associated with alterations in basal hepcidin or cytokine levels.

Gait asymmetry and running-related injury in female collegiate cross-country runners

BackgroundRunning biomechanics are commonly linked to injury. There is limited evidence on the effects of running speed on asymmetry and the prospective association of asymmetry and injury. The purposes of this study were to describe the degree in asymmetry in biomechanical variables commonly associated with injury, examine the effect of speed on asymmetry, and determine if there were any significant differences in pre-season measures of asymmetry between runners who went on to sustain an injury during the competitive season compared to those who remained healthy. MethodsThree-dimensional running biomechanics were obtained from twenty-two female collegiate cross-country runners at four different running speeds prior to their season. Asymmetry was quantified using the Symmetry Angle. Participants were followed over the twelve-week season and all time-loss injuries were identified. FindingsThere was no significant effect of velocity on asymmetry. Additionally, there were no significant differences in symmetry between runners who sustained an injury (n = 7) and those that remained injury-free (n = 15) during the cross-country season. InterpretationClinicians working with runners should expect a high degree of symmetry in running biomechanics when performing gait analyses across running speeds. In regards to injury, caution should be used when linking injury to asymmetry.

A Prolonged Bout of Running Increases Hepcidin and Decreases Dietary Iron Absorption in Trained Female and Male Runners

BackgroundDeclines in iron status are frequently reported in those who regularly engage in strenuous physical activity. A possible reason is increases in the iron regulatory hormone hepcidin, which functions to inhibit dietary iron absorption and can be induced by the inflammatory cytokine interleukin-6 (IL-6). ObjectivesThe current study aimed to determine the impact of a prolonged bout of running on hepcidin and dietary iron absorption in trained female and male runners. MethodsTrained female and male collegiate cross country runners (n = 28, age: 19.7 ± 1.2 y, maximal oxygen uptake: 66.1 ± 6.1 mL · kg −1 · min−2, serum ferritin: 21.9 ± 13.3 ng/mL) performed a prolonged run (98.8 ± 14.7 min, 21.2 ± 3.8 km, 4.7 ± 0.3 min/km) during a team practice. Participants consumed a stable iron isotope with a standardized meal 2 h postrun and blood was collected 1 h later. The protocol was repeated 2 wk later except participants abstained from exercise (rest). RBCs were collected 15 d after exercise and rest to determine isotope enrichment. Differences between exercise and rest were assessed by paired t tests and Wilcoxon matched-pairs signed rank tests. Data are means ± SDs. ResultsPlasma hepcidin increased 51% after exercise (45.8 ± 34.4 ng/mL) compared with rest (30.3 ± 27.2 ng/mL, P = 0.0010). Fractional iron absorption was reduced by 36% after exercise (11.8 ± 14.6 %) compared with rest (18.5 ± 14.4 %, P = 0.025). Plasma IL-6 was greater after exercise (0.660 ± 0.354 pg/mL) than after rest (0.457 ± 0.212 pg/mL, P < 0.0001). Exploratory analyses revealed that the increase in hepcidin with exercise may be driven by a response in males but not females. ConclusionsA prolonged bout of running increases hepcidin and decreases dietary iron absorption compared with rest in trained runners with low iron stores. The current study supports that IL-6 contributes to the increase in hepcidin with prolonged physical activity, although future studies should explore potential sex differences in the hepcidin response.This trial was registered at ClinicalTrials.gov as NCT04079322.

A hierarchical clustering approach for examining potential risk factors for bone stress injury in runners

Bone stress injuries (BSI) are overuse injuries that commonly occur in runners. BSI risk is multifactorial and not well understood. Unsupervised machine learning approaches can potentially elucidate risk factors for BSI by looking for groups of similar runners within a population that differ in BSI incidence. Here, a hierarchical clustering approach is used to identify groups of collegiate cross country runners (32 females, 21 males) based on healthy pre-season running (4.47 m·s−1) gait data which were aggregated and dimensionally reduced by principal component analysis. Five distinct groups were identified using the cluster tree. Visual inspection revealed clear differences between groups in kinematics and kinetics, and linear mixed effects models showed between-group differences in metrics potentially related to BSI risk. The groups also differed in BSI incidence during the subsequent academic year (Rand index = 0.49; adjusted Rand index = −0.02). Groups ranged from those including runners spending less time contacting the ground and generating higher peak ground reaction forces and joint moments to those including runners spending more time on the ground with lower loads. The former groups showed higher BSI incidence, indicating that short stance phases and high peak loads may be risk factors for BSI. Since ground contact duration may itself account for differences in peak loading metrics, we hypothesize that the percentage of time a runner is in contact with the ground may be a useful metric to include in machine learning models for predicting BSI risk.

Longitudinal Changes in Running Gait Asymmetries and Their Relationship to Personal Record Race Times in Collegiate Cross Country Runners

Minimizing between-limb asymmetries during running is often a goal of training, as increased asymmetries are related to decreased efficiency and increased energy expenditure. However, it is unknown if asymmetries change with increased running exposure or are related to actual race performance. The purpose of this study was to determine (1) if pre-season asymmetries changed year-to-year among collegiate cross country runners, and (2) if these asymmetries were associated with within-season personal records (PRs). Pre-season biomechanical test results and race performance data were analyzed for 54 unique runners (28 female) across six seasons, totaling 152 assessments (age: 19.1 (0.9) years, height: 1.71 (0.10) m, weight: 61.7 (7.7) kg (values = mean [standard deviation])). Biomechanical asymmetries included ground reaction forces; ground contact time; base of gait; foot inclination angle; and peak hip flexion, hip extension, hip adduction, pelvic drop, knee flexion, and ankle dorsiflexion. Year of collegiate eligibility was used to quantify training exposure. Asymmetries during running did not change across years of eligibility (p ≥ 0.12), except propulsive impulse, which decreased over time (p = 0.03). PR times were faster with decreased propulsive impulse asymmetry and increased AVLR and peak ankle dorsiflexion asymmetries. This is the first study to assess longitudinal asymmetries over time and provide potential targets for interventions aimed at modifying asymmetries to improve performance.

Asymmetries During Running Do Not Predict Bone Stress Injury In Collegiate Cross Country Runners

Asymmetries During Running Do Not Predict Bone Stress Injury In Collegiate Cross Country Runners

Monitoring Gait Complexity as an Indicator for Running-Related Injury Risk in Collegiate Cross-Country Runners: A Proof-of-Concept Study.

Dynamical systems theory suggests that studying the complexity of biological signals could lead to a single gait metric that reliably predicts risk of running-related injury (RRI). The purposes of this pilot study were to examine center of mass (COM) acceleration complexity at baseline, prior to RRI, and the change between timepoints between collegiate runners who developed RRI during a competitive season and those who remained uninjured, and to determine if complexity at these timepoints was associated with increased odds of RRI. Twenty-two collegiate runners from the same cross-country team wore a waist-mounted triaxial accelerometer (100 Hz) during easy-intensity runs throughout the competitive season. RRIs requiring medical attention were reported via an online survey. Control entropy was used to estimate the complexity of the resultant COM acceleration recorded during each run. Associations between complexity and RRI were assessed using a frequency-matching strategy where uninjured participants were paired with injured participants using complexity from the most time-proximal run prior to RRI. Seven runners sustained an RRI. No significant differences were observed between injured and uninjured groups for baseline complexity (p = 0.364, d = 0.405), pre-injury complexity (p = 0.258, d = 0.581), or change from baseline to pre-injury (p = 0.101, d = 0.963). There were no statistically significant associations found between complexity and RRI risk. Although no significant associations were found, the median effect from the models indicated that an increase in baseline complexity, pre-injury complexity, and change in complexity from baseline each corresponded to an increased odds of sustaining an RRI [baseline: odds ratio (OR) = 1.560, 95% CI = 0.587–4.143, p = 0.372; pre-injury: OR = 1.926, 95% CI: 0.689–5.382, p = 0.211; change from baseline: OR = 1.119; 95% CI: 0.839–1.491, p = 0.445). Despite non-significance and wide confidence intervals that included both positive and negative associations, the point estimates for >98% of the 10,000 frequency-case–control-matched model fits indicated that matching strategy did not influence the directionality of the association estimates between complexity and RRI risk (i.e., odds ratio >1.0). This pilot study demonstrates initial feasibility that additional research may support COM acceleration complexity as a useful single-metric monitoring system for RRI risk during real-world training. Follow-up work should assess longitudinal associations between gait complexity and running-related injury in larger cohorts.

Lower step rate is associated with a higher risk of bone stress injury: a prospective study of collegiate cross country runners

ObjectivesTo determine if running biomechanics and bone mineral density (BMD) were independently associated with bone stress injury (BSI) in a cohort of National Collegiate Athletic Association Division I cross country...

Sacral acceleration can predict whole-body kinetics and stride kinematics across running speeds.

BackgroundStress fractures are injuries caused by repetitive loading during activities such as running. The application of advanced analytical methods such as machine learning to data from multiple wearable sensors has allowed for predictions of biomechanical variables associated with running-related injuries like stress fractures. However, it is unclear if data from a single wearable sensor can accurately estimate variables that characterize external loading during running such as peak vertical ground reaction force (vGRF), vertical impulse, and ground contact time. Predicting these biomechanical variables with a single wearable sensor could allow researchers, clinicians, and coaches to longitudinally monitor biomechanical running-related injury risk factors without expensive force-measuring equipment.PurposeWe quantified the accuracy of applying quantile regression forest (QRF) and linear regression (LR) models to sacral-mounted accelerometer data to predict peak vGRF, vertical impulse, and ground contact time across a range of running speeds.MethodsThirty-seven collegiate cross country runners (24 females, 13 males) ran on a force-measuring treadmill at 3.8–5.4 m/s while wearing an accelerometer clipped posteriorly to the waistband of their running shorts. We cross-validated QRF and LR models by training them on acceleration data, running speed, step frequency, and body mass as predictor variables. Trained models were then used to predict peak vGRF, vertical impulse, and contact time. We compared predicted values to those calculated from a force-measuring treadmill on a subset of data (n = 9) withheld during model training. We quantified prediction accuracy by calculating the root mean square error (RMSE) and mean absolute percentage error (MAPE).ResultsThe QRF model predicted peak vGRF with a RMSE of 0.150 body weights (BW) and MAPE of 4.27 ± 2.85%, predicted vertical impulse with a RMSE of 0.004 BW*s and MAPE of 0.80 ± 0.91%, and predicted contact time with a RMSE of 0.011 s and MAPE of 4.68 ± 3.00%. The LR model predicted peak vGRF with a RMSE of 0.139 BW and MAPE of 4.04 ± 2.57%, predicted vertical impulse with a RMSE of 0.002 BW*s and MAPE of 0.50 ± 0.42%, and predicted contact time with a RMSE of 0.008 s and MAPE of 3.50 ± 2.27%. There were no statistically significant differences between QRF and LR model prediction MAPE for peak vGRF (p = 0.549) or vertical impulse (p = 0.073), but the LR model’s MAPE for contact time was significantly lower than the QRF model’s MAPE (p = 0.0497).ConclusionsOur findings indicate that the QRF and LR models can accurately predict peak vGRF, vertical impulse, and contact time (MAPE < 5%) from a single sacral-mounted accelerometer across a range of running speeds. These findings may be beneficial for researchers, clinicians, or coaches seeking to monitor running-related injury risk factors without force-measuring equipment.

BONE MARROW ASPIRATE CONCENTRATE INJECTION OF THE ACHILLES TENDON IN A COMPETITIVE DISTANCE RUNNER

Achilles tendon disorders, including tendinopathy and ruptures, are common among competitive runners. Relatively high complication rates, recurring injuries, and the need to return to sport have led to the use of regenerative medical treatment in tendon disorders in competitive athletes. Biologic therapies, including bone marrow aspirate concentrate (BMAC) injections, have been effective in restoring injured tissue in a limited number of cases. In this case, a collegiate cross country runner with Achilles tendon pain underwent years of failed, non-surgical conservative management. The patient’s MRI demonstrated moderate distal calcaneus tendinosis with high-grade partial thickness tearing of the anterior fibers of the Achilles tendon (50% tear). The patient underwent peritendinous injection of BMAC. Post-procedure MRI demonstrated minimal tendinosis of the distal and lateral margins of the Achilles tendon, and no evidence of Achilles tendon tear. The patient followed a progressive return to running program, ultimately training 40 miles per week with minimal Achilles tendon pain.

Normative Measures of Hip Strength and Relation to Previous Injury in Collegiate Cross-Country Runners.

Running-related injury occurs frequently in collegiate cross-country runners. Hip strength is one factor that may be important in the rehabilitation and training of cross-country runners. However, no normative values exist to inform these strategies. To establish normative values for hip-abduction and external-rotation isometric strength in collegiate cross-country runners and explore the association between strength and previous injury. Mixed methods using descriptive epidemiology and retrospective cross-sectional designs. University laboratory. Eighty-two National Collegiate Athletic Association Division III cross-country runners (38 males, 44 females). Isometric hip strength and reported injury. Males demonstrated greater absolute hip strength than females. Measures of hip strength were not different between sexes when normalized to height and mass. Hip-abduction asymmetry was associated with a previous injury in males. A combination of at least 1 leg with hip-abduction weakness and bilateral external-rotation weakness was associated with a previous injury in females. Knowledge of normative values of hip strength may help inform rehabilitation strategies in collegiate cross-country runners. Males and females may demonstrate different strength profiles after running-related injury.

Factors Associated With Self-Selected Step Rates Between Collegiate and High School Cross Country Runners.

Introduction: Cross country is a popular high school and collegiate sport with a high rate of running-related injuries (RRI). Among high school runners, higher step rates have been associated with greater running experience and decreased body height, and lower step rates have been prospectively associated with increased risk of shin RRI. These associations have not been reported in collegiate cross country runners. The purpose of this study was to compare step rates between collegiate and high school cross country runners. Secondary objectives included determining if step rates in collegiate runners were related to experience and anthropometric variables, and whether their self-selected step rates were prospectively related to lower extremity RRI.Materials and methods: Twenty-nine NCAA Division III collegiate cross country runners (13 females, mean ± SD age 19.7 ± 1.3 years) completed a survey and ran at their self-selected speed. Step rate was assessed with Polar RCX5 wristwatches and S3+ Stride Sensors™ on the first day of the season. Runners were followed during the season for occurrence of time-loss lower extremity RRI. A cohort of 68 high school runners was used for comparison of step rates at their self-selected speeds.Results: Collegiate runners' self-selected step rates (177.1 ± 7.2 spm [steps per minute]) were higher than high school runners' (171.3 ± 8.3 spm) (p = 0.01). Collegiate runners ran at higher self-selected speeds (4.6 ± 0.5 m/s) than the high school runners (3.8 ± 0.5 m/s) (p < 0.001). A lower percentage of collegiate runners ran at ≤166 spm than high school runners. Body mass was negatively correlated with step rate in collegiate runners. During the season, 41.3% of collegiate runners experienced lower extremity RRI. Step rates for collegiate runners who did not experience RRI (178.9 ± 7.7 spm) were not significantly higher than runners who did experience RRI (174.5 ± 5.7 spm) (p = 0.10).Discussion: Higher step rates were found in collegiate than high school runners, but the difference was partially explained by higher self-selected running speeds. Thus, variations in step rate between high school and collegiate runners may be expected based on experience, speed, and body mass.

Runner’s health choices questionnaire: female collegiate cross-country runners’ perspectives on health and eating

Objective To assess female collegiate cross-country runners’ perspectives regarding sport-related health and the factors impacting eating behaviors. Participants/methods The Runner’s Health Choices Questionnaire, a previously validated survey, was electronically distributed to female collegiate cross-country runners. Quantitative descriptive analysis was performed on all questions. Results A total of 353 female collegiate cross-country runners completed the survey. The most common intrinsic factors that impacted overall diet type were makes you feel healthy, enjoyment of food, and athletic performance enhancement. Extrinsic factors such as practice/race that day, creating a balanced diet, and choices in the cafeteria were the top factors influencing daily meal decisions. Seventy-seven percent of athletes reported that they would be likely to apply information from a healthcare professional if they had access. Conclusion Female cross-country runners appeared willing to apply nutritional information; therefore, it is important that generalized nutrition education with an emphasis on intrinsic and extrinsic factors for food choices be considered for female collegiate cross-country runners.

Effects of 2.4 kg of Proximal External Loading on 5-km Running Performance.

Sharp, DW, Swain, JC, Boy, TG, Killen, LG, Green, JM, and O'Neal, EK. Effects of 2.4 kg of proximal external loading on 5-km running performance. J Strength Cond Res 36(7): 1833-1838, 2022-Racing weight is a popular topic in the running community. This study examined effects of modest loading via a ∼2.4-kg soft and malleable weighted compression garment on overground running performance. Former and current collegiate cross-country runners (5 women and 6 men) completed 2 outdoor, solo road course runs 7 days apart on a familiar training route. During the first run (CON) subjects ran as closely as possible to their goal pace for a "hard speed day" workout based on predetermined paces according to current training level. During a subsequent run, subjects attempted to match their pace with aid from global positioning system watches and splits verbally announced on the course while wearing the weighted compression garment (LOAD). Metabolic data was later assessed during 5-minute running bouts on a treadmill with CON and LOAD conditions at subject's CON run pace. LOAD was slower (p < 0.01) at the 1.6-km mark (6:03 ± 0:37 vs. 6:13 ± 0:40) and finish (18:29 ± 2:06 vs. 19:15 ± 2:16). There was no differentiation (p > 0.05) between V̇o2 (CON 3.47 ± 0.86; LOAD 3.56 ± 0.77 L·min-1) or respiratory exchange ratio (CON 1.05 ± 0.06; LOAD 1.06 ± 0.04) during the 5-minute running economy bouts. There was an inverse (r = -0.42) but nonsignificant (p = 0.22) relationship between percent difference in body mass and percent difference in performance. Metabolic variable differentiation was not detectable at race pace, but 2.4 kg of proximal loading resulted in an approximately 4% acute performance impairment.

Relationship among maximum hip isometric strength, hip kinematics, and peak gluteal muscle force during running

ObjectiveTo determine if there is a relationship among isometric hip strength, hip kinematics, and peak gluteal muscle forces in cross-country runners during running. DesignCross Sectional. SettingUniversity Biomechanics Laboratory. ParticipantsForty-six NCAA Division III collegiate cross-country runners (18 males, 28 females). Main outcome measuresPearson correlation coefficients were used to describe relationships among isometric hip strength, hip kinematics, and peak gluteal muscle forces during the stance phase of running. Strength of correlations were interpreted as little to no relationship (r < 0.25), fair relationship (0.25 ≤ r < 0.5), moderate relationship (0.5 ≤ r < 0.75), and strong relationship (r ≥ 0.75). Correlations were considered significant if p < 0.05. ResultsLittle to no relationships were found among isometric hip strength and gluteal muscle forces during running (r < 0.25). A fair relationship was present between prone external rotation isometric hip strength and peak hip adduction (0.25 <r < 0.5). Little to no relationship was shown between gluteus medius force and hip internal rotation. Moderate relationships were present among peak gluteus medius and minimus muscle forces and peak hip adduction (0.5 <r < 0.75). ConclusionIsometric hip strength does not appear to be related to gluteal muscle forces and hip kinematics during the stance phase of running while gluteal muscle force was moderately related to hip adduction. Factors other than strength may be related to muscle force production and hip kinematics during running.