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Recent advances in AI and intelligent vehicle technology hold the promise of revolutionizing mobility and transportation through advanced driver assistance systems (ADAS). Certain cognitive factors, such as impulsivity and inhibitory control have been shown to relate to risky driving behavior and on-road risk-taking. However, existing systems fail to leverage such factors in assistive driving technologies adequately. Varying the levels of these cognitive factors could influence the effectiveness and acceptance of ADAS interfaces. We demonstrate an approach for personalizing driver interaction via driver safety interfaces that are are triggered based on the inference of the driver's latent cognitive states from their driving behavior. To accomplish this, we adopt a data-driven approach and train a recurrent neural network to infer impulsivity and inhibitory control from recent driving behavior. The network is trained on a population of human drivers to infer impulsivity and inhibitory control from recent driving behavior. Using data collected from a high-fidelity vehicle motion simulator experiment, we demonstrate the ability to deduce these factors from driver behavior. We then use these inferred factors to determine instantly whether or not to engage a driver safety interface. This approach was evaluated using leave-one-out cross validation using actual human data. Our evaluations reveal that our personalized driver safety interface that captures the cognitive profile of the driver is more effective in influencing driver behavior in yellow light zones by reducing their inclination to run through them.
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Conducción de Automóvil , Cognición , Humanos , Conducción de Automóvil/psicología , Cognición/fisiología , Masculino , Seguridad , Femenino , Adulto , Asunción de Riesgos , Conducta Impulsiva , Redes Neurales de la Computación , Simulación por Computador , Accidentes de Tránsito/prevención & control , Accidentes de Tránsito/psicologíaRESUMEN
Disruption of alternative splicing frequently causes or contributes to human diseases and disorders. Consequently, there is a need for efficient and sensitive reporter assays capable of screening chemical libraries for compounds with efficacy in modulating important splicing events. Here, we describe a screening workflow employing dual Nano and Firefly luciferase alternative splicing reporters that affords efficient, sensitive, and linear detection of small molecule responses. Applying this system to a screen of ~95,000 small molecules identified compounds that stimulate or repress the splicing of neuronal microexons, a class of alternative exons often disrupted in autism and activated in neuroendocrine cancers. One of these compounds rescues the splicing of several analyzed microexons in the cerebral cortex of an autism mouse model haploinsufficient for Srrm4, a major activator of brain microexons. We thus describe a broadly applicable high-throughput screening system for identifying candidate splicing therapeutics, and a resource of small molecule modulators of microexons with potential for further development in correcting aberrant splicing patterns linked to human disorders and disease.
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Empalme Alternativo , Exones , Genes Reporteros , Ensayos Analíticos de Alto Rendimiento , Luciferasas de Luciérnaga , Bibliotecas de Moléculas Pequeñas , Animales , Empalme Alternativo/efectos de los fármacos , Humanos , Ensayos Analíticos de Alto Rendimiento/métodos , Ratones , Exones/genética , Bibliotecas de Moléculas Pequeñas/farmacología , Luciferasas de Luciérnaga/genética , Luciferasas de Luciérnaga/metabolismo , Células HEK293 , Corteza Cerebral/metabolismo , Corteza Cerebral/efectos de los fármacos , Neuronas/metabolismo , Neuronas/efectos de los fármacosRESUMEN
BACKGROUND: There has been research documenting the rising numbers of racial and ethnic minority groups in the United States. With this rise, there is increasing concern over the health disparities that often affect these populations. Attention has turned to how clinicians can improve health outcomes and how the need exists to educate healthcare professionals on the practice of cultural competence. Here we present one successful approach for teaching cultural competence in the healthcare curriculum with the development of an educational session on cultural competence consisting of case-based, role-play exercises, class group discussions, online discussion boards, and a lecture PowerPoint presentation. METHODS: Cultural competence sessions were delivered in a pre-dental master's program to 178 students between 2017 and 2020. From 2017 to 2019, the sessions were implemented as in-person, case-based, role-play exercises. In 2020, due to in-person limitations caused by the COVID-19 pandemic, students were asked to read the role-play cases and provide a reflection response using the online Blackboard Learn discussion board platform. Evaluation of each session was performed using post-session survey data. RESULTS: Self-reported results from 2017 to 2020 revealed that the role-play exercises improved participant's understanding of components of cultural competence such as communication in patient encounters (95%), building rapport with patients (94%), improving patient interview skills (95%), and recognition of students own cultural biases when working with patients (93%). CONCLUSIONS: Students were able to expand their cultural awareness and humility after completion of both iterations of the course session from 2017 to 2019 and 2020. This session can be an effective method for training healthcare professionals on cultural competence.
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Competencia Cultural , Curriculum , Humanos , Competencia Cultural/educación , COVID-19 , Estados Unidos , Educación Premédica , SARS-CoV-2RESUMEN
Ultra-endurance running (UER) poses extreme mental and physical challenges that present many barriers to completion, let alone performance. Despite these challenges, participation in UER events continues to increase. With the relative paucity of research into UER training and racing compared with traditional endurance running distance (e.g., marathon), it follows that there are sizable improvements still to be made in UER if the limitations of the sport are sufficiently understood. The purpose of this review is to summarise our current understanding of the major limitations in UER. We begin with an evolutionary perspective that provides the critical background for understanding how our capacities, abilities and limitations have come to be. Although we show that humans display evolutionary adaptations that may bestow an advantage for covering large distances on a daily basis, these often far exceed the levels of our ancestors, which exposes relative limitations. From that framework, we explore the physiological and psychological systems required for running UER events. In each system, the factors that limit performance are highlighted and some guidance for practitioners and future research are shared. Examined systems include thermoregulation, oxygen delivery and utilisation, running economy and biomechanics, fatigue, the digestive system, nutritional and psychological strategies. We show that minimising the cost of running, damage to lower limb tissue and muscle fatigability may become crucial in UER events. Maintaining a sustainable core body temperature is critical to performance, and an even pacing strategy, strategic heat acclimation and individually calculated hydration all contribute to sustained performance. Gastrointestinal issues affect almost every UER participant and can be due to a variety of factors. We present nutritional strategies for different event lengths and types, such as personalised and evidence-based approaches for varying types of carbohydrate, protein and fat intake in fluid or solid form, and how to avoid flavour fatigue. Psychology plays a vital role in UER performance, and we highlight the need to be able to cope with complex situations, and that specific long and short-term goal setting improves performance. Fatigue in UER is multi-factorial, both physical and mental, and the perceived effort or level of fatigue have a major impact on the ability to continue at a given pace. Understanding the complex interplay of these limitations will help prepare UER competitors for the different scenarios they are likely to face. Therefore, this review takes an interdisciplinary approach to synthesising and illuminating limitations in UER performance to assist practitioners and scientists in making informed decisions in practice and applicable research.
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Resistencia Física , Carrera , Humanos , Resistencia Física/fisiología , Carrera/fisiología , Estado Nutricional , Regulación de la Temperatura Corporal , FatigaRESUMEN
Continuous multiday ultramarathon competitions are increasingly popular and impose extreme energetic and nutritional demands on competitors. However, few data have been published on energy expenditure during these events. Here, we report doubly labeled water-derived measures of total energy expenditure (in kilocalories per day) and estimated physical activity level (PAL: total energy expenditure/basal metabolic rate) collected from five elite and subelite finishers (four males and one female, age 34.6 ± 4.9 years)-and nutritional intake data from the winner-of the Cocodona 250, a â¼402-km race in Arizona, and from a fastest-known-time record (one male, age 30 years) on the â¼1,315-km Arizona Trail. PAL during these events exceeded four times basal metabolic rate (Cocodona range: 4.34-6.94; Arizona Trail: 5.63). Combining the results with other doubly labeled water-derived total energy expenditure data from ultraendurance events show a strong inverse relationship between event duration and PAL (r2 = .68, p < .0001). Cocodona race duration was inversely, though not significantly, associated with PAL (r2 = .70, p = .08). Water turnover varied widely between athletes and was not explained by PAL or body mass. The Cocodona race winner met â¼53% of energy demand via dietary intake, 85.6% of which was carbohydrate, while â¼47% of energy demand was met via catabolism of body energy stores. Together, these results illustrate the energetic deficits incurred during competitive continuous multiday ultramarathon efforts and implicate macronutrient absorption and/or storage as key factors in ultramarathon performance.
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Ingestión de Alimentos , Metabolismo Energético , Humanos , Masculino , Femenino , Adulto , Metabolismo Basal , Agua , Atletas , Ingestión de EnergíaRESUMEN
OBJECTIVES: We aim to test three questions regarding human eccrine sweat gland density, which is highly derived yet poorly understood. First, is variation in functional eccrine gland density ("FED") explained by childhood climate, suggesting phenotypic plasticity? Second, is variation in FED explained by genetic similarity (a proxy for "geographic ancestry"), implying divergent evolutionary pathways in this trait of ancestral populations? Third, what is the relationship between FED and sweat production? MATERIALS AND METHODS: To test questions one and two, we measured FED in 68 volunteers aged 18-39 with varied childhood climate regimes and geographic ancestries. To test question three, we compared sweat production to FED in our n = 68 sample. In addition, we examined the relationship between FED and whole-body sweat loss during cycling in warm conditions using a sample of eight heat-acclimated endurance athletes. RESULTS: Interindividual variation in six-site FED was more than twofold, ranging from 60.9 to 132.7 glands/cm2 . Variation in FED was best explained by body surface area and limb circumferences (negative associations) and poorly explained by childhood climatic conditions and genetic similarity. Pilocarpine-induced sweat production was unrelated to FED while whole-body sweat loss during cycling was significantly, though modestly, associated with FED. DISCUSSION: We hypothesize that gland-level phenotypic plasticity, rather than changes in eccrine gland density, was sufficient to permit thermal adaptation to novel environments as humans colonized the globe. Future research should measure effects of FED in dehydrated states and the relationship between FED and salt loss, and control for effects of microclimate to rule out phenotypic plasticity effects.
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Glándulas Ecrinas , Sudoración , Humanos , Niño , Glándulas Ecrinas/metabolismo , Sudor , Pilocarpina/metabolismoRESUMEN
Alternative splicing (AS) is a critical regulatory layer; yet, factors controlling functionally coordinated splicing programs during developmental transitions are poorly understood. Here, we employ a screening strategy to identify factors controlling dynamic splicing events important for mammalian neurogenesis. Among previously unknown regulators, Rbm38 acts widely to negatively control neural AS, in part through interactions mediated by the established repressor of splicing, Ptbp1. Puf60, a ubiquitous factor, is surprisingly found to promote neural splicing patterns. This activity requires a conserved, neural-differential exon that remodels Puf60 co-factor interactions. Ablation of this exon rewires distinct AS networks in embryonic stem cells and at different stages of mouse neurogenesis. Single-cell transcriptome analyses further reveal distinct roles for Rbm38 and Puf60 isoforms in establishing neuronal identity. Our results describe important roles for previously unknown regulators of neurogenesis and establish how an alternative exon in a widely expressed splicing factor orchestrates temporal control over cell differentiation.
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Neurogénesis , Empalme del ARN , Empalme Alternativo , Animales , Exones/genética , Mamíferos , Ratones , Neurogénesis/genética , Neuronas , Proteínas de Unión al ARN/genéticaRESUMEN
BACKGROUND: The severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) pandemic threatened to oversaturate hospitals worldwide, necessitating rapid patient discharge to preserve capacity for the most severe cases. This need, as well as the high risk of SARS-CoV-2 transmission, led many hospitals to implement remote patient monitoring (RPM) programs for SARS-CoV-2 positive patients in an effort to provide care that was safe and preserve scarce resources. OBJECTIVE: The aim of this study is to provide an integrative review of peer-reviewed literature on different RPM programs that were implemented for SARS-CoV-2 positive patients including their strengths and challenges. METHODS: A search was conducted for peer reviewed literature using PubMed, CINAHL, OVID, and Google Scholar. Peer-reviewed studies written in English or Spanish and published between 2019 and 2021 on RPM of SARS-CoV-2-positive patients were considered. Information was extracted according to a qualitative content analysis method, informed by the Comparison of Mobile Patient Monitoring Systems Framework. RESULTS: Of 57 retrieved articles, 10 publications were included. The sample sizes ranged from 75 to 48,290 and the monitoring length ranged from 7 to 30 days. Information regarding the comparison framework was summarized. Main strengths of using RPM for SARS-CoV-2 positive patients was participant acceptance, feasibility, safety, and resource conservation. Main limitations were the lack of information on patient data security measures, robust outcomes testing, and identification of the most effective biomarkers to track SARS-CoV-2 decompensation. CONCLUSION: Different RPM programs for SARS-CoV-2 were implemented, from sending home participants with a pulse oximeter and collecting readings via call to modifying existing mobile applications and sending holistic health questionnaires to participants. This review determined that RPM is beneficial to SARS-CoV-2 positive patients; however, its effectiveness can be improved by further research. Mainly, identifying what patient data are most effective at tracking SARS-CoV-2 decompensation by utilizing advanced technology already in the market.
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COVID-19 , SARS-CoV-2 , Humanos , PandemiasRESUMEN
PURPOSE: Currently, calculations of proton range in proton therapy patients are based on a conversion of CT Hounsfield units of patient tissues into proton relative stopping power. Uncertainties in this conversion necessitate larger proximal and distal planned target volume margins. Proton CT can potentially reduce these uncertainties by directly measuring proton stopping power. We aim to demonstrate proton CT imaging with complex porcine samples, to analyze in detail three-dimensional regions of interest, and to compare proton stopping powers directly measured by proton CT to those determined from x-ray CT scans. METHODS: We have used a prototype proton imaging system with single proton tracking to acquire proton radiography and proton CT images of a sample of porcine pectoral girdle and ribs, and a pig's head. We also acquired close in time x-ray CT scans of the same samples and compared proton stopping power measurements from the two modalities. In the case of the pig's head, we obtained x-ray CT scans from two different scanners and compared results from high-dose and low-dose settings. RESULTS: Comparing our reconstructed proton CT images with images derived from x-ray CT scans, we find agreement within 1% to 2% for soft tissues and discrepancies of up to 6% for compact bone. We also observed large discrepancies, up to 40%, for cavitated regions with mixed content of air, soft tissue, and bone, such as sinus cavities or tympanic bullae. CONCLUSIONS: Our images and findings from a clinically realistic proton CT scanner demonstrate the potential for proton CT to be used for low-dose treatment planning with reduced margins.
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Terapia de Protones , Animales , Humanos , Fantasmas de Imagen , Protones , Radiografía , Planificación de la Radioterapia Asistida por Computador , Porcinos , Tomografía Computarizada por Rayos X , Rayos XRESUMEN
OBJECTIVE: The specificity of training principle holds that adaptations to exercise training closely match capacity to the specific demands of the stimulus. Improvements in endurance sport performance gained through strength training are a notable exception to this principle. While the proximate mechanisms for how strength training produces muscular adaptations beneficial to endurance sports are increasingly well understood, the ultimate causes of this phenomenon remain unexplored. METHODS: Using a holistic approach tying together exercise physiology and evolution, I argue that we can reconcile the apparent "endurance training specificity paradox." RESULTS AND CONCLUSIONS: Competing selective pressures, inherited mammalian biology, and millennia of living in energy-scarce environments constrained our evolution as endurance athletes, but also imparted high muscular plasticity which can be exploited to improve endurance performance beyond what was useful in our evolutionary past.
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Entrenamiento de Fuerza , Deportes , Adaptación Fisiológica , Ejercicio Físico , Humanos , Músculo Esquelético , Resistencia FísicaRESUMEN
Chimeric antigen receptor (CAR) T cell therapy has shown promise in hematologic malignancies, but its application to solid tumors has been challenging1-4. Given the unique effector functions of macrophages and their capacity to penetrate tumors5, we genetically engineered human macrophages with CARs to direct their phagocytic activity against tumors. We found that a chimeric adenoviral vector overcame the inherent resistance of primary human macrophages to genetic manipulation and imparted a sustained pro-inflammatory (M1) phenotype. CAR macrophages (CAR-Ms) demonstrated antigen-specific phagocytosis and tumor clearance in vitro. In two solid tumor xenograft mouse models, a single infusion of human CAR-Ms decreased tumor burden and prolonged overall survival. Characterization of CAR-M activity showed that CAR-Ms expressed pro-inflammatory cytokines and chemokines, converted bystander M2 macrophages to M1, upregulated antigen presentation machinery, recruited and presented antigen to T cells and resisted the effects of immunosuppressive cytokines. In humanized mouse models, CAR-Ms were further shown to induce a pro-inflammatory tumor microenvironment and boost anti-tumor T cell activity.
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Inmunoterapia Adoptiva , Macrófagos/fisiología , Neoplasias/terapia , Animales , Línea Celular Tumoral , Supervivencia Celular , Humanos , Inmunoterapia , Neoplasias Pulmonares/terapia , Ratones , Microscopía por Video , Neoplasias ExperimentalesRESUMEN
The human eccrine sweat gland is central to the evolution of the human genus, permitting an enormous thermoregulatory sweating capacity that was essential to the human niche of high physical activity in open, hot, semi-arid environments. Despite a century of research inventorying the structure and function of eccrine glands and the physiological responses of human heat acclimation, we do not have a clear understanding of how intraspecific differences in eccrine density affect thermoregulation. Similarly, existing data does not comprehensively catalogue modern human diversity in this trait, nor do we understand the relative influences of evolutionary forces and phenotypic plasticity in shaping this diversity.
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Aclimatación/fisiología , Glándulas Ecrinas/fisiología , Sudoración/fisiología , Evolución Biológica , Calor , HumanosRESUMEN
We present a real-time algorithm to infer the intention of a user's avatar in a virtual environment shared with multiple human-like agents. Our algorithm applies the Bayesian Theory of Mind approach to make inferences about the avatar's hidden intentions based on the observed proxemics and gaze-based cues. Our approach accounts for the potential irrationality in human behavior, as well as the dynamic nature of an individual's intentions. The inferred intent is used to guide the response of the virtual agent and generate locomotion and gaze-based behaviors. Our overall approach allows the user to actively interact with tens of virtual agents from a first-person perspective in an immersive setting. We systematically evaluate our inference algorithm in controlled multi-agent simulation environments and highlight its ability to reliably and efficiently infer the hidden intent of a user's avatar even under noisy conditions. We quantitatively demonstrate the performance benefits of our approach in terms of reducing false inferences, as compared to a prior method. The results of our user evaluation show that 68.18% of participants reported feeling more comfortable in sharing the virtual environment with agents simulated with our algorithm as compared to a prior inference method, likely as a direct result of significantly fewer false inferences and more plausible responses from the virtual agents.
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Gráficos por Computador , Procesamiento de Imagen Asistido por Computador/métodos , Realidad Virtual , Adulto , Algoritmos , Teorema de Bayes , Señales (Psicología) , Femenino , Humanos , Intención , MasculinoRESUMEN
INTRODUCTION: Extragonadal locations of teratomas are uncommonly reported in the literature. Teratomas are neoplasms usually found in the gonadal organs: ovaries and testis. The majority of teratomas are found in the pediatric age group. Furthermore, teratomas originating in the liver are exceedingly rare with only 11 case reports in adult populations. PRESENTATION OF CASE: We present a case of a 65 year-old female who presented to hospital with sudden onset abdominal pain from a centrally located ruptured hepatic teratoma on CT scan. The patient underwent urgent surgery. The diagnosis of cystic mature teratoma was confirmed on histopathology. Patient was discharged on post-operative day 5. At 12 week follow-up, no post-operative complications were identified. DISCUSSION: Hepatic teratomas are a rarely encountered neoplasm, especially in the adult population. Our case report is unique, as it represents the only clinical presentation of mass rupture in an adult liver teratoma. CT scan identified a well circumscribed mass containing adipose tissue, fluid, and calcifications characteristic of teratoma. Complete surgical resection is mainstay treatment. A definitive diagnosis of a mature teratoma is confirmed by histopathological findings. CONCLUSION: Presented is a rare case of ruptured hepatic teratoma in an adult who underwent surgical resection.
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Alternative splicing is crucial for diverse cellular, developmental, and pathological processes. However, the full networks of factors that control individual splicing events are not known. Here, we describe a CRISPR-based strategy for the genome-wide elucidation of pathways that control splicing and apply it to microexons with important functions in nervous system development and that are commonly misregulated in autism. Approximately 200 genes associated with functionally diverse regulatory layers and enriched in genetic links to autism control neuronal microexons. Remarkably, the widely expressed RNA binding proteins Srsf11 and Rnps1 directly, preferentially, and frequently co-activate these microexons. These factors form critical interactions with the neuronal splicing regulator Srrm4 and a bi-partite intronic splicing enhancer element to promote spliceosome formation. Our study thus presents a versatile system for the identification of entire splicing regulatory pathways and further reveals a common mechanism for the definition of neuronal microexons that is disrupted in autism.
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Empalme Alternativo/fisiología , Ingeniería Genética/métodos , Sitios de Empalme de ARN/fisiología , Animales , Trastorno Autístico/genética , Sistemas CRISPR-Cas/genética , Línea Celular , Exones/fisiología , Humanos , Ratones , Proteínas del Tejido Nervioso , Neurogénesis , Neuronas , Precursores del ARN/fisiología , Empalme del ARN/fisiología , Proteínas de Unión al ARN , Ribonucleoproteínas , Factores de Empalme Serina-Arginina , EmpalmosomasRESUMEN
Alternative splicing (AS) is a widespread process underlying the generation of transcriptomic and proteomic diversity and is frequently misregulated in human disease. Accordingly, an important goal of biomedical research is the development of tools capable of comprehensively, accurately, and efficiently profiling AS. Here, we describe Whippet, an easy-to-use RNA-seq analysis method that rapidly-with hardware requirements compatible with a laptop-models and quantifies AS events of any complexity without loss of accuracy. Using an entropic measure of splicing complexity, Whippet reveals that one-third of human protein coding genes produce transcripts with complex AS events involving co-expression of two or more principal splice isoforms. We observe that high-entropy AS events are more prevalent in tumor relative to matched normal tissues and correlate with increased expression of proto-oncogenic splicing factors. Whippet thus affords the rapid and accurate analysis of AS events of any complexity, and as such will facilitate future biomedical research.
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Empalme Alternativo/genética , Proteómica , Empalme del ARN/genética , Análisis de Secuencia de ARN/métodos , Perfilación de la Expresión Génica/métodos , Humanos , Anotación de Secuencia Molecular , ARN Mensajero/genética , TranscriptomaRESUMEN
Sweating is an unusual thermoregulatory strategy for most mammals, yet is critical for humans. This trait is commonly hypothesized to result from human ancestors moving from a forest to a warmer and drier open environment. As soft tissue traits do not typically fossilize, this idea has been difficult to test. Therefore, we used a comparative approach to examine 15 eccrine gland traits from 35 primate species. For each trait we measured phylogenetic signal, tested three evolutionary models to explain trait variation, and used phylogenetic models to examine how traits varied in response to climate variables. Phylogenetic signal in traits varied substantially, with the two traits exhibiting the highest values being gland distribution on the body and percent eccrine vs. apocrine glands on the body. Variation in most traits was best explained by an Ornstein-Uhlenbeck model suggesting the importance of natural selection. Two traits were strongly predicted by climate. First, species with high eccrine gland glycogen content were associated with habitats exhibiting warm temperatures and low rainfall. Second, species with increased capillarization were associated with high temperature. Glycogen is a primary energy substrate powering sweat production and sodium reabsorption in the eccrine gland, and increased capillarization permits greater oxygen, glucose and electrolyte delivery. Thus, our results are evidence of natural selection for increased sweating capacity in primate species with body surface eccrine glands living in hot and dry climates. We suggest that selection for increased glycogen content and capillarization may have been part of initial increases in hominin thermoregulatory sweating capacity.
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Evolución Biológica , Glándulas Ecrinas/fisiología , Ecosistema , Primates/fisiología , Animales , Glándulas Ecrinas/química , HumanosRESUMEN
[This corrects the article DOI: 10.1371/journal.pone.0188200.].
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Trabecular bone of the human calcaneus is subjected to extreme repetitive forces during endurance running and should adapt in response to this strain. To assess possible bone functional adaptation in the posterior region of the calcaneus, we recruited forefoot-striking runners (n = 6), rearfoot-striking runners (n = 6), and non-runners (n = 6), all males aged 20-41 for this institutionally approved study. Foot strike pattern was confirmed for each runner using a motion capture system. We obtained high resolution peripheral computed tomography scans of the posterior calcaneus for both runners and non-runners. No statistically significant differences were found between runners and nonrunners or forefoot strikers and rearfoot strikers. Mean trabecular thickness and mineral density were greatest in forefoot runners with strong effect sizes (<0.80). Trabecular thickness was positively correlated with weekly running distance (r2 = 0.417, p<0.05) and years running (r2 = 0.339, p<0.05) and negatively correlated with age at onset of running (r2 = 0.515, p<0.01) Trabecular thickness, mineral density and bone volume ratio of nonrunners were highly correlated with body mass (r2 = 0.824, p<0.05) and nonrunners were significantly heavier than runners (p<0.05). Adjusting for body mass revealed significantly thicker trabeculae in the posterior calcaneus of forefoot strikers, likely an artifact of greater running volume and earlier onset of running in this subgroup; thus, individuals with the greatest summative loading stimulus had, after body mass adjustment, the thickest trabeculae. Further study with larger sample sizes is necessary to elucidate the role of footstrike on calcaneal trabecular structure. To our knowledge, intraspecific body mass correlations with measures of trabecular robusticity have not been reported elsewhere. We hypothesize that early adoption of running and years of sustained moderate volume running stimulate bone modeling in trabeculae of the posterior calcaneus.