Pub Date : 2026-01-28DOI: 10.1249/mss.0000000000003947
Garry F Dredge,Daniel I Rhon,Abe R Dummar,Brian W Noehren,Johanna M Hoch,Nicholas R Heebner
BACKGROUND/PURPOSEFemoral neck bone stress injuries (FNBSIs) are severe overuse injuries associated with high rates of non-completion of training and medical separation in military personnel. While the negative impact of an FNBSI diagnosis is known, it remains unclear how specific MRI-defined injury characteristics, such as grade, location, and unilateral vs. bilateral presentation, relate to graduation outcomes. This study aimed to determine the association between these FNBSI characteristics and graduation from Basic Combat Training (BCT).METHODSIn this matched retrospective cohort study of 208,540 U.S. Army trainees (2015-2019), trainees with MRI-confirmed FNBSIs (n=682) were matched 1:3 by sex and age to controls without bone stress injuries (n=2,046). Logistic regression was used to model the associations between FNBSI features and BCT graduation.RESULTSGraduation rates were significantly lower for trainees with an FNBSI, with matched controls having seven times higher odds of graduating (OR=7.38, 95% CI: 5.95-9.16). Lower MRI grades were associated with significantly higher odds of graduation (e.g., Grade 1 vs. 3, OR=4.65), while bilateral injuries were associated with lower odds of graduation than unilateral injuries (OR=0.72, 95% CI: 0.53-0.98). No significant difference was observed between compression- and tension-sided injuries. In the matched cohort, male sex and older age were also associated with higher graduation odds.CONCLUSIONSFNBSIs are strongly associated with lower odds of completing BCT, particularly when injuries are bilateral, of a higher MRI grade, or occur in younger or female trainees. These findings highlight the critical need for early detection, standardized reporting of MRI injury characteristics, and targeted interventions to improve military training retention.
{"title":"MRI Findings of Femoral Neck Bone Stress Injuries in Army Trainees and Their Association with Basic Training Graduation: A Retrospective Cohort Study.","authors":"Garry F Dredge,Daniel I Rhon,Abe R Dummar,Brian W Noehren,Johanna M Hoch,Nicholas R Heebner","doi":"10.1249/mss.0000000000003947","DOIUrl":"https://doi.org/10.1249/mss.0000000000003947","url":null,"abstract":"BACKGROUND/PURPOSEFemoral neck bone stress injuries (FNBSIs) are severe overuse injuries associated with high rates of non-completion of training and medical separation in military personnel. While the negative impact of an FNBSI diagnosis is known, it remains unclear how specific MRI-defined injury characteristics, such as grade, location, and unilateral vs. bilateral presentation, relate to graduation outcomes. This study aimed to determine the association between these FNBSI characteristics and graduation from Basic Combat Training (BCT).METHODSIn this matched retrospective cohort study of 208,540 U.S. Army trainees (2015-2019), trainees with MRI-confirmed FNBSIs (n=682) were matched 1:3 by sex and age to controls without bone stress injuries (n=2,046). Logistic regression was used to model the associations between FNBSI features and BCT graduation.RESULTSGraduation rates were significantly lower for trainees with an FNBSI, with matched controls having seven times higher odds of graduating (OR=7.38, 95% CI: 5.95-9.16). Lower MRI grades were associated with significantly higher odds of graduation (e.g., Grade 1 vs. 3, OR=4.65), while bilateral injuries were associated with lower odds of graduation than unilateral injuries (OR=0.72, 95% CI: 0.53-0.98). No significant difference was observed between compression- and tension-sided injuries. In the matched cohort, male sex and older age were also associated with higher graduation odds.CONCLUSIONSFNBSIs are strongly associated with lower odds of completing BCT, particularly when injuries are bilateral, of a higher MRI grade, or occur in younger or female trainees. These findings highlight the critical need for early detection, standardized reporting of MRI injury characteristics, and targeted interventions to improve military training retention.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146056342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-28DOI: 10.1249/mss.0000000000003950
Ann E Rogers,Amanda Prokasky,Mary J Von Seggern,David A Dzewaltowski,Michaela A Schenkelberg
PURPOSEThis cross-sectional study used data from the 2021-2022 National Survey of Children's Health to examine the sociodemographic characteristics associated with youth sport (YS) participation in the United States by state among youth aged 6 to 17 years. The study also examined state-level associations between YS participation and meeting physical activity (PA) guidelines.METHODSA logistic regression model evaluated the associations of sociodemographic characteristics of age, sex, race/ethnicity, household income, special health care needs (SHCN) status, and health insurance type with YS participation by state. Rao-Scott chi-square tests computed by state determined whether YS participation was associated with meeting PA guidelines.RESULTSThe analytic sample included 64,535 youth. Approximately 51% reported past-year YS participation (range = 39.8%-64.6% across states). Household income was significantly associated with YS participation for 43 states. Youth from lower income households had lower odds of participating in sport than youth from higher income households (OR range = 0.24-0.49). In 35 states, youth with SHCN had lower odds of participating in sport than youth without SHCN (OR range = 0.35-0.72). Race/ethnicity and age were significantly associated with YS participation in 13 and 7 states, respectively, and the sociodemographic subgroups more likely to participate varied by geographic location. YS participation was significantly associated with meeting PA guidelines in 20 states.CONCLUSIONSYS is a critical developmental setting for youth. Youth with lower incomes and SHCN were consistently less likely to participate in sport than their peers. Associations between other sociodemographic characteristics (e.g., race/ethnicity) and YS participation varied geospatially, highlighting the need for state-specific approaches to improve YS so that all youth have opportunities to participate.
{"title":"Geospatial and Sociodemographic Variability in Youth Sport Participation: 2021-2022 National Survey of Children's Health.","authors":"Ann E Rogers,Amanda Prokasky,Mary J Von Seggern,David A Dzewaltowski,Michaela A Schenkelberg","doi":"10.1249/mss.0000000000003950","DOIUrl":"https://doi.org/10.1249/mss.0000000000003950","url":null,"abstract":"PURPOSEThis cross-sectional study used data from the 2021-2022 National Survey of Children's Health to examine the sociodemographic characteristics associated with youth sport (YS) participation in the United States by state among youth aged 6 to 17 years. The study also examined state-level associations between YS participation and meeting physical activity (PA) guidelines.METHODSA logistic regression model evaluated the associations of sociodemographic characteristics of age, sex, race/ethnicity, household income, special health care needs (SHCN) status, and health insurance type with YS participation by state. Rao-Scott chi-square tests computed by state determined whether YS participation was associated with meeting PA guidelines.RESULTSThe analytic sample included 64,535 youth. Approximately 51% reported past-year YS participation (range = 39.8%-64.6% across states). Household income was significantly associated with YS participation for 43 states. Youth from lower income households had lower odds of participating in sport than youth from higher income households (OR range = 0.24-0.49). In 35 states, youth with SHCN had lower odds of participating in sport than youth without SHCN (OR range = 0.35-0.72). Race/ethnicity and age were significantly associated with YS participation in 13 and 7 states, respectively, and the sociodemographic subgroups more likely to participate varied by geographic location. YS participation was significantly associated with meeting PA guidelines in 20 states.CONCLUSIONSYS is a critical developmental setting for youth. Youth with lower incomes and SHCN were consistently less likely to participate in sport than their peers. Associations between other sociodemographic characteristics (e.g., race/ethnicity) and YS participation varied geospatially, highlighting the need for state-specific approaches to improve YS so that all youth have opportunities to participate.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"102 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146056769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-28DOI: 10.1249/mss.0000000000003946
Stanley Smith,Susan Sigward,Nicholas Schweighofer,Rachel K Straub,Christopher M Powers
PURPOSETo determine if distinct landing strategies could be delineated that could inform higher exposure to ACL injury. We also sought to determine whether greater proportion of females would be assigned to a higher exposure cluster.METHODSKinematic and kinetic data from 74 healthy athletes (31 males and 43 females) were obtained during a drop-jump task. Variables of interest included those previously shown in prospective studies to be predictive of future ACL injury. K-means clustering (k=2) was used to determine if two (or more) distinct strategies could be delineated. Independent T-tests were used to assess between-cluster differences for each biomechanical variable of interest. A chi-square test was utilized to explore the distribution of males and females across the two clusters.RESULTSK-means clustering categorized participants into 2 groups (Cluster 1: N=36; Cluster 2: N=38). Two distinct landing strategies were identified as evident by the finding of statistically significant between cluster differences in 7 of the 8 biomechanical variables evaluated. Of these differences, 6 have been identified in the literature as being predictive of future ACL injury. The proportion of females assigned to Cluster 1 was 69.4% (N= 25), compared to 30.6% males (N=11).CONCLUSIONSThe results of this study revealed that the drop-jump task can be used to characterize distinct landing strategies. Based on the coexistence of suspected risk factors, an argument could be made that Cluster 1 may be representative of a landing strategy representative of elevated exposure to ACL injury.
{"title":"Characterizing Landing Strategies During the Drop Jump Task: A Proposed Data-Driven Approach to Identify Increased Exposure to Non-Contact ACL Injury.","authors":"Stanley Smith,Susan Sigward,Nicholas Schweighofer,Rachel K Straub,Christopher M Powers","doi":"10.1249/mss.0000000000003946","DOIUrl":"https://doi.org/10.1249/mss.0000000000003946","url":null,"abstract":"PURPOSETo determine if distinct landing strategies could be delineated that could inform higher exposure to ACL injury. We also sought to determine whether greater proportion of females would be assigned to a higher exposure cluster.METHODSKinematic and kinetic data from 74 healthy athletes (31 males and 43 females) were obtained during a drop-jump task. Variables of interest included those previously shown in prospective studies to be predictive of future ACL injury. K-means clustering (k=2) was used to determine if two (or more) distinct strategies could be delineated. Independent T-tests were used to assess between-cluster differences for each biomechanical variable of interest. A chi-square test was utilized to explore the distribution of males and females across the two clusters.RESULTSK-means clustering categorized participants into 2 groups (Cluster 1: N=36; Cluster 2: N=38). Two distinct landing strategies were identified as evident by the finding of statistically significant between cluster differences in 7 of the 8 biomechanical variables evaluated. Of these differences, 6 have been identified in the literature as being predictive of future ACL injury. The proportion of females assigned to Cluster 1 was 69.4% (N= 25), compared to 30.6% males (N=11).CONCLUSIONSThe results of this study revealed that the drop-jump task can be used to characterize distinct landing strategies. Based on the coexistence of suspected risk factors, an argument could be made that Cluster 1 may be representative of a landing strategy representative of elevated exposure to ACL injury.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"65 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146056343","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-28DOI: 10.1249/mss.0000000000003951
Julianne D Schmidt,Kumiko Hashida,Julia Drattell,Robert C Lynall,Kim Love,Hannes Devos,Russell K Gore
PURPOSETo determine whether simulated driving performance improves as days since concussion increase.METHODSCross-sectional study. Forty-nine young-adult patients diagnosed with concussion (19.3 ± 1.5 years, Female 61.2%) completed a driving simulation assessment at an initial clinic visit between 0-12 days post-concussion. Primary outcome variables included total number of collisions, speed exceedances, stop signs missed, lane excursions, total drive time, percent time over the speed limit, and percent time out of the lane. For each of the 11 drive segments, we examined the average speed, standard deviation of speed (SDS), average lateral lane position, and standard deviation of lateral lane position (SDLP). Driving simulation outcomes were modeled using a negative binomial regression for count variables and linear regression for continuous variables, using the predictor of days since concussion.RESULTSFewer days since concussion were associated with more frequent centerline crossings (p=0.046); greater time spent out of the lane (p=0.045); a lateral lane position closer to the centerline while navigating a left residential curve (p<0.001) and while incurring a vehicle in the lane (p=0.026); greater SDLP while navigating a crosswalk (p<0.001) and while navigating around a crash in the road (p=0.018).CONCLUSIONSClinicians should consider recommendations that support limited driving during the acute stages (24-72 hours) of concussion followed by a gradual return to driving. A longitudinal study design in a larger sample is needed to better define driving performance recovery following concussion.
{"title":"Driving After Concussion: The Influence of Days Since Concussion on Simulated Driving Performance Recovery.","authors":"Julianne D Schmidt,Kumiko Hashida,Julia Drattell,Robert C Lynall,Kim Love,Hannes Devos,Russell K Gore","doi":"10.1249/mss.0000000000003951","DOIUrl":"https://doi.org/10.1249/mss.0000000000003951","url":null,"abstract":"PURPOSETo determine whether simulated driving performance improves as days since concussion increase.METHODSCross-sectional study. Forty-nine young-adult patients diagnosed with concussion (19.3 ± 1.5 years, Female 61.2%) completed a driving simulation assessment at an initial clinic visit between 0-12 days post-concussion. Primary outcome variables included total number of collisions, speed exceedances, stop signs missed, lane excursions, total drive time, percent time over the speed limit, and percent time out of the lane. For each of the 11 drive segments, we examined the average speed, standard deviation of speed (SDS), average lateral lane position, and standard deviation of lateral lane position (SDLP). Driving simulation outcomes were modeled using a negative binomial regression for count variables and linear regression for continuous variables, using the predictor of days since concussion.RESULTSFewer days since concussion were associated with more frequent centerline crossings (p=0.046); greater time spent out of the lane (p=0.045); a lateral lane position closer to the centerline while navigating a left residential curve (p<0.001) and while incurring a vehicle in the lane (p=0.026); greater SDLP while navigating a crosswalk (p<0.001) and while navigating around a crash in the road (p=0.018).CONCLUSIONSClinicians should consider recommendations that support limited driving during the acute stages (24-72 hours) of concussion followed by a gradual return to driving. A longitudinal study design in a larger sample is needed to better define driving performance recovery following concussion.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"64 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146056345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
PURPOSEVestibular dysfunction (VD) is associated with fall risk and is more common in older adults with mild cognitive impairment (OAwMCI) than cognitively intact older adults (CIOA). However, it is unknown if VD contributes to the reactive balance deficits observed in OAwMCI (e.g., higher fall rate, lower reactive center of mass (COM) stability).METHODSThis study examined how VD affected reactive stepping kinematics and neuromuscular control in OAwMCI (n=28) and CIOA (n=35) when exposed to a large anterior support surface perturbation. VD was identified by a positive score on ≥2/3 clinical tests (Head thrust, Vestibular ocular reflex (VOR) slow, VOR cancellation), and was more common in OAwMCI (46%) than CIOA (23%) (p<0.05).RESULTSOnly OAwMCI with VD showed higher fall rate, lower reactive COM stability, delayed step initiation, and longer onset latencies of the bilateral medial gastrocnemius than those without VD (significant group*VD interaction, p<0.05). However, both OAwMCI and CIOA with VD showed longer step execution, reduced activation amplitude of the stepping limb hamstrings and tibialis anterior during step initiation and execution (relative to peak activation), and longer burst durations of the stepping limb quadriceps than those without VD (significant main effect of VD, p<0.05).CONCLUSIONSThis suggests that VD may affect reactive balance control in OAwMCI more than CIOA by interfering with reactive step triggering/initiation, although may affect reactive step execution in both CIOA and OAwMCI. Vestibular inputs may contribute to both perturbation detection/response triggering and motor execution, and OAwMCI may have reduced capacity to compensate for unreliable vestibular sensory inputs due to impaired sensory reweighting. Comprehensive fall risk screenings could consider the combination of both cognitive decline and VD.
{"title":"Combined Effects of Vestibular Dysfunction and Mild Cognitive Impairment on Reactive Stepping Responses in Older Adults.","authors":"Jessica Pitts,Tej Mehta,Lakshmi Kannan,Shuaijie Wang,Mahaziver Master,Upasana Sahu,Swaranka Deshmukh,Rudri Purohit,Tanvi Bhatt","doi":"10.1249/mss.0000000000003945","DOIUrl":"https://doi.org/10.1249/mss.0000000000003945","url":null,"abstract":"PURPOSEVestibular dysfunction (VD) is associated with fall risk and is more common in older adults with mild cognitive impairment (OAwMCI) than cognitively intact older adults (CIOA). However, it is unknown if VD contributes to the reactive balance deficits observed in OAwMCI (e.g., higher fall rate, lower reactive center of mass (COM) stability).METHODSThis study examined how VD affected reactive stepping kinematics and neuromuscular control in OAwMCI (n=28) and CIOA (n=35) when exposed to a large anterior support surface perturbation. VD was identified by a positive score on ≥2/3 clinical tests (Head thrust, Vestibular ocular reflex (VOR) slow, VOR cancellation), and was more common in OAwMCI (46%) than CIOA (23%) (p<0.05).RESULTSOnly OAwMCI with VD showed higher fall rate, lower reactive COM stability, delayed step initiation, and longer onset latencies of the bilateral medial gastrocnemius than those without VD (significant group*VD interaction, p<0.05). However, both OAwMCI and CIOA with VD showed longer step execution, reduced activation amplitude of the stepping limb hamstrings and tibialis anterior during step initiation and execution (relative to peak activation), and longer burst durations of the stepping limb quadriceps than those without VD (significant main effect of VD, p<0.05).CONCLUSIONSThis suggests that VD may affect reactive balance control in OAwMCI more than CIOA by interfering with reactive step triggering/initiation, although may affect reactive step execution in both CIOA and OAwMCI. Vestibular inputs may contribute to both perturbation detection/response triggering and motor execution, and OAwMCI may have reduced capacity to compensate for unreliable vestibular sensory inputs due to impaired sensory reweighting. Comprehensive fall risk screenings could consider the combination of both cognitive decline and VD.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146056377","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-28DOI: 10.1249/mss.0000000000003949
Catherine C Donahue,Katherine L Smulligan,Mathew J Wingerson,Joshua R Kniss,Julie C Wilson,David R Howell
BACKGROUNDThe Post Concussion Symptom Inventory (PCSI) evaluates the severity of 21 concussion-related symptoms, yielding a total symptom severity between 0-126. Although widely used in concussion research and care as a key element in diagnosis and management decisions, no clinically validated cut point exists to distinguish adolescents with and without a recent concussion. Therefor the purpose of our study was to establish a PCSI cut point with adequate sensitivity, specificity, and classification accuracy for clinical use.METHODSAdolescents within 21 days of concussion and uninjured controls completed the PCSI, and total symptom severity score was calculated. We used independent samples t-tests to compare total PCSI symptom severity scores between groups, and multivariable logistic regression to calculate adjusted odds ratios (outcome=group, predictor=PCSI score, covariates=age, biological sex, concussion history, history of anxiety and/or depression). A receiver operator characteristic (ROC) curve was used to evaluate the area under the ROC curve (AUC) and determine the optimal cut point to distinguish between adolescents with/without a concussion.RESULTS153 adolescents with a concussion (15.4±1.6 years; 54% female; 8.2±3.6 days since injury), and 200 uninjured controls (15.8±1.1 years; 84% female) were included. The concussion group had significantly higher PCSI scores than the control group (47.4±26.8 vs. 20.9±19.4; p<0.001). The univariable AUC value for the PCSI to differentiate between groups was 0.80 (95% confidence interval [CI]=0.75,0.85), and correctly classified 74% of participants as concussion or control group using a PCSI cut point of 23 (sensitivity=68%, specificity=83%).CONCLUSIONSOur results suggest a PCSI cut point of 23 can distinguish between adolescents with/without a recent concussion and may provide enhanced accuracy to identify a suspected concussion in the subacute time after injury.
{"title":"Clinical Cut Point for the Post Concussion Symptom Inventory Following Adolescent Concussion.","authors":"Catherine C Donahue,Katherine L Smulligan,Mathew J Wingerson,Joshua R Kniss,Julie C Wilson,David R Howell","doi":"10.1249/mss.0000000000003949","DOIUrl":"https://doi.org/10.1249/mss.0000000000003949","url":null,"abstract":"BACKGROUNDThe Post Concussion Symptom Inventory (PCSI) evaluates the severity of 21 concussion-related symptoms, yielding a total symptom severity between 0-126. Although widely used in concussion research and care as a key element in diagnosis and management decisions, no clinically validated cut point exists to distinguish adolescents with and without a recent concussion. Therefor the purpose of our study was to establish a PCSI cut point with adequate sensitivity, specificity, and classification accuracy for clinical use.METHODSAdolescents within 21 days of concussion and uninjured controls completed the PCSI, and total symptom severity score was calculated. We used independent samples t-tests to compare total PCSI symptom severity scores between groups, and multivariable logistic regression to calculate adjusted odds ratios (outcome=group, predictor=PCSI score, covariates=age, biological sex, concussion history, history of anxiety and/or depression). A receiver operator characteristic (ROC) curve was used to evaluate the area under the ROC curve (AUC) and determine the optimal cut point to distinguish between adolescents with/without a concussion.RESULTS153 adolescents with a concussion (15.4±1.6 years; 54% female; 8.2±3.6 days since injury), and 200 uninjured controls (15.8±1.1 years; 84% female) were included. The concussion group had significantly higher PCSI scores than the control group (47.4±26.8 vs. 20.9±19.4; p<0.001). The univariable AUC value for the PCSI to differentiate between groups was 0.80 (95% confidence interval [CI]=0.75,0.85), and correctly classified 74% of participants as concussion or control group using a PCSI cut point of 23 (sensitivity=68%, specificity=83%).CONCLUSIONSOur results suggest a PCSI cut point of 23 can distinguish between adolescents with/without a recent concussion and may provide enhanced accuracy to identify a suspected concussion in the subacute time after injury.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"78 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146056344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
OBJECTIVESWhile sexual dimorphism of knee osteoarthritis (KOA) is well established, sex-specific clinical manifestations-particularly involving peri-articular tissues undetectable by radiography-remain underexplored. This study aimed to define female-specific alterations in joint integrity, peri-articular muscle quality, symptom presentation, and the transcriptomic landscape of peri-articular muscles, with the goal of uncovering the mechanistic contributions of each to KOA pathophysiology.METHODSForty-nine participants (32 females, 17 males; Kellgren-Lawrence grade 1-2) underwent clinical assessment, including (1) quantitative ultrasound assessment of the vastus medialis (VM) and rectus femoris (RF) muscles; (2) MRI to assess joint integrity; and (3) patient-reported outcomes. Principal component analysis (PCA) followed by receiver operating characteristic curve analysis were conducted to identify discriminative sex-specific imaging and symptom features. Correlation-based network analysis examined sex-specific interdependencies among clinical variables. Publicly available transcriptomic datasets were analyzed to identify molecular drivers underlying female-specific muscle quality changes.RESULTSDespite similar radiographic severity and symptom presentation across the sexes, female individuals exhibited greater cartilage degeneration and higher fatty infiltration in the VM and RF. These features were central to sex separation in the PCA, with both features identified as network hubs in female individuals, indicating interconnected muscle-joint degeneration. Transcriptomic analysis revealed enrichment of adipogenic reprogramming in female individuals, suggesting aberrant intramuscular fat programming.DISCUSSIONSOur findings uncover a distinct female-specific musculoskeletal phenotype in early-stage KOA, characterized by muscle degeneration and cartilage deterioration undetectable by radiography. These female-specific clinical manifestations may be due, at least partly, to aberrant adipogenic programming in muscle. These findings provide mechanistic and clinical insight into sexual dimorphism in KOA.
{"title":"Sexual Dimorphism in Clinical Manifestations of Knee Osteoarthritis.","authors":"Atsushi Hoki,Tsubasa Iwasaki,Yoshikazu Matsuda,Fabrisia Ambrosio,Hirotaka Iijima","doi":"10.1249/mss.0000000000003944","DOIUrl":"https://doi.org/10.1249/mss.0000000000003944","url":null,"abstract":"OBJECTIVESWhile sexual dimorphism of knee osteoarthritis (KOA) is well established, sex-specific clinical manifestations-particularly involving peri-articular tissues undetectable by radiography-remain underexplored. This study aimed to define female-specific alterations in joint integrity, peri-articular muscle quality, symptom presentation, and the transcriptomic landscape of peri-articular muscles, with the goal of uncovering the mechanistic contributions of each to KOA pathophysiology.METHODSForty-nine participants (32 females, 17 males; Kellgren-Lawrence grade 1-2) underwent clinical assessment, including (1) quantitative ultrasound assessment of the vastus medialis (VM) and rectus femoris (RF) muscles; (2) MRI to assess joint integrity; and (3) patient-reported outcomes. Principal component analysis (PCA) followed by receiver operating characteristic curve analysis were conducted to identify discriminative sex-specific imaging and symptom features. Correlation-based network analysis examined sex-specific interdependencies among clinical variables. Publicly available transcriptomic datasets were analyzed to identify molecular drivers underlying female-specific muscle quality changes.RESULTSDespite similar radiographic severity and symptom presentation across the sexes, female individuals exhibited greater cartilage degeneration and higher fatty infiltration in the VM and RF. These features were central to sex separation in the PCA, with both features identified as network hubs in female individuals, indicating interconnected muscle-joint degeneration. Transcriptomic analysis revealed enrichment of adipogenic reprogramming in female individuals, suggesting aberrant intramuscular fat programming.DISCUSSIONSOur findings uncover a distinct female-specific musculoskeletal phenotype in early-stage KOA, characterized by muscle degeneration and cartilage deterioration undetectable by radiography. These female-specific clinical manifestations may be due, at least partly, to aberrant adipogenic programming in muscle. These findings provide mechanistic and clinical insight into sexual dimorphism in KOA.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146056376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-23DOI: 10.1249/mss.0000000000003938
Kelly B Elliott,Marcos S Keefe,Ryan A Dunn,Ty B Palmer,Adam S Lepley,Yasuki Sekiguchi
PURPOSETo examine the effect of hydration status on neuromuscular performance prior to and following intermittent exercise in the heat.METHODSEleven male soccer players (age, 20±2 years; height, 179.0±7.9 cm; body mass, 74.9±10.3 kg; Maximal Oxygen consumption, 62.4 ± 11.5 mL·kg-1·min-1) performed a familiarization trial involving ultrasound (cross-sectional area [CSA] and muscle thickness), landing error scoring system (LESS), and isometric knee extensions (rate of torque development [RTD]; time intervals of 0-30 ms (RTD 30), 0-50 ms (RTD 50), 0-100 ms (RTD 100), and 0-200 ms (RTD 200) from contraction onset). Following this, participants completed 45-minutes of intermittent exercise in the heat (33°C, 30% relative humidity) as part of familiarization. Experimental trials replicated the same protocol of pre- and post-neuromuscular testing separated by two 45-minute intermittent exercise bouts in the heat. Two experimental trials (euhydrated [EUH] and hypohydrated [HYP]) were randomly assigned; EUH, maintained euhydration throughout trial; HYP, performed a 24-hour fluid restriction before the trial. Prior to and following exercise, urine specific gravity (USG), urine osmolality, and body mass loss (BML) were measured. A linear mixed effect model with Tukey post hoc was utilized to assess differences between trials.RESULTSCSA of the rectus femoris was smaller in HYP pre (13.3±2.4 cm2) compared to EUH pre (14.0±2.6 cm2), and in HYP post (12.7±2.4 cm2) compared to EUH post (14.0±2.6 cm2) (p<0.05). Independent of time, muscle thickness was also smaller in HYP (2.27±0.2 cm) compared to EUH (2.45±0.2 cm, p<0.05). Furthermore, LESS scores were higher in HYP (4.1±2.0) compared to EUH (2.9±2.0, p<0.05). RTD30, 50, and 100 were all lower in HYP (326±138 Nm·s-1; 441±207 Nm·s-1; 648±302 Nm·s -1) compared to EUH (427±175 Nm·s-1; 584±282 Nm·s -1; 796±392 Nm·s-1, p<0.05), respectively. Additionally, USG, urine osmolality, and BML, were all higher in HYP compared to EUH (p<0.05).CONCLUSIONSHypohydration can negatively impact neuromuscular performance prior to and following intermittent exercise in the heat.
目的研究高温间歇运动前后水合状态对神经肌肉功能的影响。方法6名男性足球运动员（年龄20±2岁，身高179.0±7.9 cm，体重74.9±10.3 kg，最大耗氧量62.4±11.5 mL·kg-1·min-1）进行熟悉性试验，包括超声（横截面积[CSA]和肌肉厚度）、落地失误评分系统（LESS）和等距膝关节伸展（扭矩发展率[RTD]；从收缩开始的0-30 ms （RTD 30）、0-50 ms （RTD 50）、0-100 ms （RTD 100）和0-200 ms （RTD 200）时间间隔）。在此之后，参与者在高温（33°C， 30%相对湿度）下完成45分钟的间歇性运动，作为熟悉的一部分。实验试验重复了神经肌肉测试前和测试后的相同方案，在高温下进行两次45分钟的间歇运动。试验随机分为两组（EUH和HYP）；EUH，在整个试验过程中保持低水合作用；HYP在试验前进行了24小时的液体限制。运动前后分别测量尿比重（USG）、尿渗透压和体重损失（BML）。采用Tukey post hoc线性混合效应模型来评估试验间的差异。结果HYP组股直肌scsa（13.3±2.4 cm2）小于EUH组（14.0±2.6 cm2）， HYP组股直肌scsa（12.7±2.4 cm2）小于EUH组（14.0±2.6 cm2） （p<0.05）。与时间无关，HYP组肌肉厚度（2.27±0.2 cm）小于EUH组（2.45±0.2 cm）， p<0.05。HYP组的LESS评分（4.1±2.0）高于EUH组（2.9±2.0,p<0.05）。RTD30、rtd50和rtd100在HYP中的表达（326±138 Nm·s-1、441±207 Nm·s-1、648±302 Nm·s-1）均低于EUH（427±175 Nm·s-1、584±282 Nm·s-1、796±392 Nm·s-1, p<0.05）。此外，高血压组的USG、尿渗透压和BML均高于高血压组（p<0.05）。结论高温间歇运动前后的脱水会对神经肌肉机能产生负面影响。
{"title":"Hypohydration Decreases Neuromuscular Performance Prior to and Following Intermittent Exercise in the Heat.","authors":"Kelly B Elliott,Marcos S Keefe,Ryan A Dunn,Ty B Palmer,Adam S Lepley,Yasuki Sekiguchi","doi":"10.1249/mss.0000000000003938","DOIUrl":"https://doi.org/10.1249/mss.0000000000003938","url":null,"abstract":"PURPOSETo examine the effect of hydration status on neuromuscular performance prior to and following intermittent exercise in the heat.METHODSEleven male soccer players (age, 20±2 years; height, 179.0±7.9 cm; body mass, 74.9±10.3 kg; Maximal Oxygen consumption, 62.4 ± 11.5 mL·kg-1·min-1) performed a familiarization trial involving ultrasound (cross-sectional area [CSA] and muscle thickness), landing error scoring system (LESS), and isometric knee extensions (rate of torque development [RTD]; time intervals of 0-30 ms (RTD 30), 0-50 ms (RTD 50), 0-100 ms (RTD 100), and 0-200 ms (RTD 200) from contraction onset). Following this, participants completed 45-minutes of intermittent exercise in the heat (33°C, 30% relative humidity) as part of familiarization. Experimental trials replicated the same protocol of pre- and post-neuromuscular testing separated by two 45-minute intermittent exercise bouts in the heat. Two experimental trials (euhydrated [EUH] and hypohydrated [HYP]) were randomly assigned; EUH, maintained euhydration throughout trial; HYP, performed a 24-hour fluid restriction before the trial. Prior to and following exercise, urine specific gravity (USG), urine osmolality, and body mass loss (BML) were measured. A linear mixed effect model with Tukey post hoc was utilized to assess differences between trials.RESULTSCSA of the rectus femoris was smaller in HYP pre (13.3±2.4 cm2) compared to EUH pre (14.0±2.6 cm2), and in HYP post (12.7±2.4 cm2) compared to EUH post (14.0±2.6 cm2) (p<0.05). Independent of time, muscle thickness was also smaller in HYP (2.27±0.2 cm) compared to EUH (2.45±0.2 cm, p<0.05). Furthermore, LESS scores were higher in HYP (4.1±2.0) compared to EUH (2.9±2.0, p<0.05). RTD30, 50, and 100 were all lower in HYP (326±138 Nm·s-1; 441±207 Nm·s-1; 648±302 Nm·s -1) compared to EUH (427±175 Nm·s-1; 584±282 Nm·s -1; 796±392 Nm·s-1, p<0.05), respectively. Additionally, USG, urine osmolality, and BML, were all higher in HYP compared to EUH (p<0.05).CONCLUSIONSHypohydration can negatively impact neuromuscular performance prior to and following intermittent exercise in the heat.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146021495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-23DOI: 10.1249/mss.0000000000003942
Laura Lecompte,Marion Crouzier,Stijn Bogaerts,Benedicte Vanwanseele
PURPOSEIntra-tendinous sliding, i.e. non-uniform motions between the superficial and deep layers of the Achilles tendon, is reduced in individuals with Achilles tendinopathy compared to healthy controls during isometric contractions. Previous work has shown that intra-tendinous sliding can be increased by performing isometric contractions with a horizontally outward-rotated ("toes-out") foot position. The purpose of this study was to compare intra-tendinous sliding between healthy individuals and patients with Achilles tendinopathy during dynamic exercises, and to determine the effect of a toes-out foot position.METHODSForty participants (20 healthy and 20 Achilles tendinopathy) performed dynamic exercises, including bilateral heel rise/drop (sitting & standing), unilateral heel rise/drop (knee extended & bent) and squat. Exercises were performed in a neutral and toes-out foot position, with ultrasound images captured using an external probeholder. Intra-tendinous sliding (mm) was estimated via a speckle tracking algorithm as the difference between displacement of the superficial and deep layers of the Achilles tendon.RESULTSMain effects of group, foot position and exercise were found indicating that Achilles tendinopathy patients have reduced intra-tendinous sliding, that intra-tendinous sliding can be increased in a toes-out foot position and that some exercises induce more intra-tendinous sliding than others.CONCLUSIONSThese findings support intra-tendinous sliding as a marker of tendon health and suggest that foot positioning may be a simple way to enhance sliding. Given the poor rehabilitation outcomes for Achilles tendinopathy patients, implementing an external foot position during rehabilitation protocols could offer a low-cost and easy-to-implement method to improve rehabilitation success rates.
{"title":"Patients with Achilles Tendinopathy show Reduced Intra-tendinous Sliding during Dynamic Exercises.","authors":"Laura Lecompte,Marion Crouzier,Stijn Bogaerts,Benedicte Vanwanseele","doi":"10.1249/mss.0000000000003942","DOIUrl":"https://doi.org/10.1249/mss.0000000000003942","url":null,"abstract":"PURPOSEIntra-tendinous sliding, i.e. non-uniform motions between the superficial and deep layers of the Achilles tendon, is reduced in individuals with Achilles tendinopathy compared to healthy controls during isometric contractions. Previous work has shown that intra-tendinous sliding can be increased by performing isometric contractions with a horizontally outward-rotated (\"toes-out\") foot position. The purpose of this study was to compare intra-tendinous sliding between healthy individuals and patients with Achilles tendinopathy during dynamic exercises, and to determine the effect of a toes-out foot position.METHODSForty participants (20 healthy and 20 Achilles tendinopathy) performed dynamic exercises, including bilateral heel rise/drop (sitting & standing), unilateral heel rise/drop (knee extended & bent) and squat. Exercises were performed in a neutral and toes-out foot position, with ultrasound images captured using an external probeholder. Intra-tendinous sliding (mm) was estimated via a speckle tracking algorithm as the difference between displacement of the superficial and deep layers of the Achilles tendon.RESULTSMain effects of group, foot position and exercise were found indicating that Achilles tendinopathy patients have reduced intra-tendinous sliding, that intra-tendinous sliding can be increased in a toes-out foot position and that some exercises induce more intra-tendinous sliding than others.CONCLUSIONSThese findings support intra-tendinous sliding as a marker of tendon health and suggest that foot positioning may be a simple way to enhance sliding. Given the poor rehabilitation outcomes for Achilles tendinopathy patients, implementing an external foot position during rehabilitation protocols could offer a low-cost and easy-to-implement method to improve rehabilitation success rates.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146021494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-01-23DOI: 10.1249/mss.0000000000003939
Paul A Baker,Sam R Moore,Gabrielle M DelBiondo,Olga R Ilkayeva,Christopher B Newgard,Abbie E Smith-Ryan
PURPOSEThe extent to which these exercise strategies alter metabolomic signatures of macronutrient metabolism in T1D is unknown. The current study evaluated glycemic variability and metabolomic responses around energy matched HIIT and MICT in individuals with T1D.METHODSFourteen adults with T1D (7 females, 7 males) completed three conditions in a randomized crossover design: HIIT (10 one-minute intervals at 90% VO2peak), MICT (15-20 mins steady-state cycling at 65% VO2peak), and no exercise (control, CON). 24-hr glycemic responses via continuous glucose monitor (CGM) and metabolomics assessed by blood samples before, after, and 1-hour after exercise by targeted mass spectrometry and non-targeted gas chromatography-mass spectrometry.RESULTSAverage whole-day glucose levels were higher on the day of HIIT (167.48±66.96mg/dL; group×time p=0.021) and MICT (166.46±61.35mg/dL; group×time p=0.039) compared to CON (150.43±61.69mg/dL) with no difference between HIIT and MICT (group×time p=0.999). Area under the curve for glucose was not different between HIIT, MICT, and CON on the day of exercise (group×time p=0.961). After MICT, long-chain acylcarnitine C14:2 (0.06±0.04µmol/L) was higher than after HIIT (0.04±0.02µmol/L; group×time p=0.008), with C16:1 (group×time p=0.046) and C16:2 (group×time p=0.021) higher than CON.CONCLUSIONSIn adults with T1D, HIIT and MICT elevated average glucose on the day of exercise, with greater fatty acid oxidation after MICT. These data support the metabolic safety and distinct fuel utilization of both exercise modalities in T1D.
{"title":"Metabolic Effects of Isoenergetic High Intensity Interval Training and Moderate Intensity Continuous Training in Adults with Type I Diabetes.","authors":"Paul A Baker,Sam R Moore,Gabrielle M DelBiondo,Olga R Ilkayeva,Christopher B Newgard,Abbie E Smith-Ryan","doi":"10.1249/mss.0000000000003939","DOIUrl":"https://doi.org/10.1249/mss.0000000000003939","url":null,"abstract":"PURPOSEThe extent to which these exercise strategies alter metabolomic signatures of macronutrient metabolism in T1D is unknown. The current study evaluated glycemic variability and metabolomic responses around energy matched HIIT and MICT in individuals with T1D.METHODSFourteen adults with T1D (7 females, 7 males) completed three conditions in a randomized crossover design: HIIT (10 one-minute intervals at 90% VO2peak), MICT (15-20 mins steady-state cycling at 65% VO2peak), and no exercise (control, CON). 24-hr glycemic responses via continuous glucose monitor (CGM) and metabolomics assessed by blood samples before, after, and 1-hour after exercise by targeted mass spectrometry and non-targeted gas chromatography-mass spectrometry.RESULTSAverage whole-day glucose levels were higher on the day of HIIT (167.48±66.96mg/dL; group×time p=0.021) and MICT (166.46±61.35mg/dL; group×time p=0.039) compared to CON (150.43±61.69mg/dL) with no difference between HIIT and MICT (group×time p=0.999). Area under the curve for glucose was not different between HIIT, MICT, and CON on the day of exercise (group×time p=0.961). After MICT, long-chain acylcarnitine C14:2 (0.06±0.04µmol/L) was higher than after HIIT (0.04±0.02µmol/L; group×time p=0.008), with C16:1 (group×time p=0.046) and C16:2 (group×time p=0.021) higher than CON.CONCLUSIONSIn adults with T1D, HIIT and MICT elevated average glucose on the day of exercise, with greater fatty acid oxidation after MICT. These data support the metabolic safety and distinct fuel utilization of both exercise modalities in T1D.","PeriodicalId":18500,"journal":{"name":"Medicine & Science in Sports & Exercise","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2026-01-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146021496","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：