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  1. Article ; Online: Eccentric, but not concentric blood flow restriction resistance training increases muscle strength in the untrained limb.

    Hill, Ethan C

    Physical therapy in sport : official journal of the Association of Chartered Physiotherapists in Sports Medicine

    2020  Volume 43, Page(s) 1–7

    Abstract: Objectives: Little is known regarding the variables or mechanisms mediating cross-education as a result of resistance training. Therefore, the purpose of the present study was to examine the effects of low-load eccentric-only blood flow restriction (Ecc- ...

    Abstract Objectives: Little is known regarding the variables or mechanisms mediating cross-education as a result of resistance training. Therefore, the purpose of the present study was to examine the effects of low-load eccentric-only blood flow restriction (Ecc-BFR) and low-load concentric-only BFR (Con-BFR) on indices of cross-education.
    Design: Thirty-six women were randomly assigned to 4-wks of unilateral resistance training with Ecc-BFR (n = 12), Con-BFR (n = 12) or control (no intervention, n = 12) group. Eccentric peak torque, concentric peak torque, maximal voluntary isometric contraction torque, muscle thickness, and muscle activation were assessed from the contralateral, untrained arm.
    Results: Muscle strength (collapsed across mode) increased from 0-wk to 2-wks (4.9%) and 4-wks (13.0%) for Ecc-BFR only. There were increases in muscle activation (collapsed across mode and group) regardless of training modality, but there were no changes in muscle size for any of the conditions.
    Conclusions: The findings of the present study indicated that low-load Ecc-BFR increased muscle strength. The increases in muscle strength as a result of Ecc-BFR were not mode-specific. Thus, low-load Ecc-BFR provides a unique alternative to maintain muscle function in an untrained limb that may have application during limb immobilization and rehabilitation practices.
    MeSH term(s) Brachial Artery/diagnostic imaging ; Female ; Humans ; Isometric Contraction ; Muscle Strength ; Muscle, Skeletal/diagnostic imaging ; Regional Blood Flow ; Resistance Training/methods ; Torque ; Ultrasonography ; Upper Extremity/blood supply ; Upper Extremity/diagnostic imaging ; Young Adult
    Language English
    Publishing date 2020-01-30
    Publishing country England
    Document type Journal Article ; Randomized Controlled Trial
    ZDB-ID 2008604-0
    ISSN 1873-1600 ; 1466-853X
    ISSN (online) 1873-1600
    ISSN 1466-853X
    DOI 10.1016/j.ptsp.2020.01.013
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  2. Article ; Online: Low bone mineral density is associated with fatty liver disease and respiratory illness in a pediatric mortality sample.

    Hill, Ethan C / O'Donnell, Lexi

    Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA

    2023  Volume 34, Issue 7, Page(s) 1231–1239

    Abstract: This study finds that fatty liver disease is associated with low bone density in a pediatric mortality sample. Since non-alcoholic fatty liver disease has increased in prevalence over the past few decades among children, a better understanding of the ... ...

    Abstract This study finds that fatty liver disease is associated with low bone density in a pediatric mortality sample. Since non-alcoholic fatty liver disease has increased in prevalence over the past few decades among children, a better understanding of the disease's impacts on bone health is of significance to clinicians.
    Purpose: Chronic illness leads to decreased bone modeling and remodeling. This can be especially problematic during childhood and adolescence, since the majority of an individual's peak bone mass is achieved by the age of 20. In this study, we examine relationships between chronic illness and low bone mineral density (BMD) in a pediatric mortality sample (aged 0.5 to 20.9 years) from New Mexico. We also test whether low BMD is related to decelerated linear growth by examining its relationship to growth stunting and arrest (Harris lines).
    Methods: Hounsfield units (HU), a proxy for trabecular BMD, were obtained at the fourth lumbar vertebra and the femoral neck from postmortem CT scans. Linear regression was used to examine associations between z-standardized HU and age, sex, medical conditions, Harris lines, and growth stunting.
    Results: We find that lumbar HU is significantly lower for individuals with fatty liver disease and respiratory illness; femoral HU is significantly lower in individuals with Harris lines.
    Conclusion: The mechanisms of low BMD in individuals with fatty liver disease and respiratory illness are likely multifactorial and involve vitamin D deficiency (malnutrition, malabsorption), systemic inflammation, and sedentary lifestyles. However, better awareness of this relationship can provide clinicians with the ability to introduce nutritional and behavioral interventions early to mitigate deleterious effects on bone. Harris lines, on the other hand, mark temporary growth cessation due to physiological stress followed by a rapid resumption of growth. Low BMD in these individuals may be due to bone mineralization lagging behind relatively rapid linear growth.
    MeSH term(s) Adolescent ; Humans ; Child ; Non-alcoholic Fatty Liver Disease ; Absorptiometry, Photon ; Bone Density/physiology ; Bone Diseases, Metabolic ; Femur Neck ; Lumbar Vertebrae
    Language English
    Publishing date 2023-04-21
    Publishing country England
    Document type Journal Article
    ZDB-ID 1064892-6
    ISSN 1433-2965 ; 0937-941X
    ISSN (online) 1433-2965
    ISSN 0937-941X
    DOI 10.1007/s00198-023-06760-4
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  3. Article ; Online: Perinatal Disorders and Small Birthweight Are Significantly Associated With Small Vertebral Neural Canal Size in a Contemporary Pediatric Autopsy Sample.

    O'Donnell, Lexi / Corron, Louise K / Hill, Ethan C

    Spine

    2023  Volume 48, Issue 11, Page(s) E158–E168

    Abstract: Study design: A retrospective, nonblinded, single-center observational study.: Objective: The purpose of this study is to examine associations between small vertebral neural canal (VNC) measurements with verified experiences of early-life stress (ELS) ...

    Abstract Study design: A retrospective, nonblinded, single-center observational study.
    Objective: The purpose of this study is to examine associations between small vertebral neural canal (VNC) measurements with verified experiences of early-life stress (ELS) (premature birth, disorders or conditions arising in the perinatal period, and congenital disorders) in a pediatric autopsy sample, paired with other skeletal indicators of stress, and known demographic/health information.
    Summary of background data: Most studies linking small VNC size to ELS are for human remains from archeological sites without known demographic information or health history, making it difficult to assess what kind of stress might affect VNC growth.
    Methods: This is a single-center retrospective study in a pediatric autopsy sample of 623 individuals (aged 0.5 to 20.9 yr) with known sex, age, and manner of death (MOD), who died between 2011 and 2019. Data were collected from postmortem computed tomography scans, autopsy, and field investigator reports. Data include VNC anteroposterior and transverse (TR) diameters of the 12th thoracic (T12) and fifth lumbar (L5) vertebrae, bone mineral density, and Harris lines.
    Results: Small birthweight males have significantly smaller VNC than those with an average birthweight. The natural MOD is associated with smaller VNC. Perinatal disorders and growth stunting are associated with smaller T12 anteroposterior, T12-TR, and L5-TR diameters. Congenital disorders and Harris lines are not associated with small VNC.
    Conclusions: Reduced VNC size is a reliable indicator of severe ELS, but not all ELS leads to reduced VNC. Females appear less susceptible to perinatal environmental stress than males. Reduced VNC may also be indicative of heightened risk of disease and death in those who died of natural MOD.
    Level of evidence: Level 2.
    MeSH term(s) Male ; Pregnancy ; Female ; Humans ; Child ; Retrospective Studies ; Birth Weight ; Autopsy ; Neural Tube ; Spine/diagnostic imaging
    Language English
    Publishing date 2023-03-13
    Publishing country United States
    Document type Observational Study ; Journal Article
    ZDB-ID 752024-4
    ISSN 1528-1159 ; 0362-2436
    ISSN (online) 1528-1159
    ISSN 0362-2436
    DOI 10.1097/BRS.0000000000004628
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  4. Article ; Online: Biocultural and social determinants of ill health and early mortality in a New Mexican paediatric autopsy sample.

    O'Donnell, Lexi / Green, John J / Hill, Ethan C / O'Donnell, Michael J

    Journal of biosocial science

    2024  , Page(s) 1–22

    Abstract: Results.: Hispanic children have higher odds of growth stunting than non-Hispanic White children. Native American children die younger and have higher odds of respiratory diseases and porous lesions than Hispanic and non-Hispanic Whites. Rural/urban ... ...

    Abstract Results.: Hispanic children have higher odds of growth stunting than non-Hispanic White children. Native American children die younger and have higher odds of respiratory diseases and porous lesions than Hispanic and non-Hispanic Whites. Rural/urban location does not significantly impact age at death, but housing type does. Individuals who lived in trailers/mobile homes had earlier ages at death. When intersections between housing type and housing location are considered, children who were poor and from impoverished areas lived longer than those who were poor from relatively well-off areas.
    Conclusions.: Children's health is shaped by factors outside their control. The children included in this study embodied experiences of social and ELS and did not survive to adulthood. They provide the most sobering example of the harm that social factors (structural racism/discrimination, socioeconomic, and political structures) can inflict.
    Language English
    Publishing date 2024-04-15
    Publishing country England
    Document type Journal Article
    ZDB-ID 390961-x
    ISSN 1469-7599 ; 0021-9320
    ISSN (online) 1469-7599
    ISSN 0021-9320
    DOI 10.1017/S0021932024000129
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  5. Article: Neuromuscular Responses to Failure vs Non-Failure During Blood Flow Restriction Training in Untrained Females.

    Proppe, Christopher E / Aldeghi, Taylor M / Rivera, Paola M / Gonzalez-Rojas, David H / Hill, Ethan C

    International journal of exercise science

    2023  Volume 16, Issue 1, Page(s) 293–303

    Abstract: Applying blood flow restriction (BFR) during resistance exercise is a potent stimulus of muscular adaption, but there is little direct comparison of its effect on neuromuscular function. The purpose of this investigation was to compare surface ... ...

    Abstract Applying blood flow restriction (BFR) during resistance exercise is a potent stimulus of muscular adaption, but there is little direct comparison of its effect on neuromuscular function. The purpose of this investigation was to compare surface electromyography amplitude and frequency responses during a 75 (1 × 30, 3 × 15) repetition bout (BFR-75) of BFR to 4 sets to failure (BFR-F). Twelve women (mean ± SD age = 22 ± 4 years; body mass = 72 ± 14.4 kg; height = 162.1 ± 4.0 cm) volunteered for the investigation. One leg was randomly assigned to complete BFR-75 and the other to BFR-F. Each leg performed isokinetic, unilateral, concentric-eccentric, leg extension at 30% of maximal strength while surface electromyographic (sEMG) data was recorded. More repetitions (
    Language English
    Publishing date 2023-02-01
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2411342-6
    ISSN 1939-795X
    ISSN 1939-795X
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  6. Article ; Online: Skeletal manifestations of disease experience: Length of illness and porous cranial lesion formation in a contemporary juvenile mortality sample.

    O'Donnell, Lexi / Buikstra, Jane E / Hill, Ethan C / Anderson, Amy S / O'Donnell, Michael J

    American journal of human biology : the official journal of the Human Biology Council

    2023  Volume 35, Issue 8, Page(s) e23896

    Abstract: Objectives: Porous lesions of the orbit (cribra orbitalia [CO]) and cranial vault (porotic hyperostosis [PH]) are used as skeletal indicators of childhood stress. Because they are understudied in contemporary populations, their relationship to disease ... ...

    Abstract Objectives: Porous lesions of the orbit (cribra orbitalia [CO]) and cranial vault (porotic hyperostosis [PH]) are used as skeletal indicators of childhood stress. Because they are understudied in contemporary populations, their relationship to disease experience is poorly understood. This paper examines the relationship between length of childhood illness and CO/PH formation in a clinically documented sample. "Turning points," which identify the window for lesion formation for CO/PH, are defined, implications for hidden heterogeneity in frailty are considered.
    Methods: Data are from 333 (199 males; 134 females) pediatric postmortem computed tomography scans. Individuals died in New Mexico (2011-2019) and are 0.5 to 15.99 years (mean = 7.1). Length of illness was estimated using information from autopsy and field reports. Logistic regression was used to estimate predicted probabilities, odds ratios, and the temporal window for lesion formation.
    Results: Illness, single bouts, or cumulative episodes lasting over 1 month is associated with higher odds of CO; individuals who were never sick have lower odds of having PH. This relationship was consistent for fatal and incidental illnesses that did not cause death. The developmental window for CO formation appears to close at 8 years.
    Conclusions: Those ill for over 1 month are more likely to have CO/PH than those with acute illnesses. Some individuals lived sufficiently long to form CO/PH but died of illness. Others with lesions died of circumstances unrelated to disease. This indicates hidden variation in robusticity even among ill individuals with CO/PH, which is vital in interpreting lesion frequencies in the archeological record.
    MeSH term(s) Male ; Female ; Humans ; Child ; Porosity ; Skull/pathology ; Orbit/pathology ; Hyperostosis/complications ; Hyperostosis/pathology ; New Mexico
    Language English
    Publishing date 2023-03-28
    Publishing country United States
    Document type Journal Article
    ZDB-ID 1025339-7
    ISSN 1520-6300 ; 1042-0533
    ISSN (online) 1520-6300
    ISSN 1042-0533
    DOI 10.1002/ajhb.23896
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  7. Article ; Online: Effects of load matched isokinetic versus isotonic blood flow restricted exercise on neuromuscular and muscle function.

    Rivera, Paola M / Proppe, Christopher E / Gonzalez-Rojas, David / Wizenberg, Aaron / Hill, Ethan C

    European journal of sport science

    2023  Volume 23, Issue 8, Page(s) 1629–1637

    Abstract: The purpose of this investigation was to examine neuromuscular function, muscle fatigue, rating of perceived exertion (RPE), and muscle swelling between isokinetic and isotonic leg extensions with blood flow restriction (BFR). Fourteen (21 ± 2years; ... ...

    Abstract The purpose of this investigation was to examine neuromuscular function, muscle fatigue, rating of perceived exertion (RPE), and muscle swelling between isokinetic and isotonic leg extensions with blood flow restriction (BFR). Fourteen (21 ± 2years; 160cm ± 3.8; 61kg ± 9.1) trained women performed 75 (1 × 30,3 × 15) submaximal (30% of maximal strength), unilateral, isokinetic and isotonic leg extensions with BFR (60% of total arterial occlusion pressure). Before and after exercise, subjects performed maximal voluntary isometric contractions (MVIC) and muscle thickness (MT) was assessed with ultrasound. RPE was recorded across all sets and surface electromyography (EMG) was assessed during the MVIC muscle actions. Separate repeated measures ANOVAs were used to examine MVIC, MT, RPE and neuromuscular function. There were greater reductions in MVIC torque and EMG mean power frequency following isotonic (46.2 ± 17.1%; 16.4 ± 7.9%) than isokinetic (17.9 ± 10.9%;6.5 ± 6.3%). RPE was also higher during isotonic (7.5 ± 2.2), than isokinetic (5.7 ± 1.9). There were no differences in EMG amplitude or MT increases (20 ± 2.1%) between conditions. Isotonic BFR elicited greater fatigue-induced decreases in muscular strength and greater RPE than isokinetic BFR, but similar MT and muscle excitation responses for both conditions. Therefore, both isokinetic and isotonic may induce similar acute physiological responses, but isotonic BFR was associated with greater muscle fatigue and perceived effort.
    MeSH term(s) Humans ; Female ; Muscle, Skeletal/physiology ; Muscle Fatigue/physiology ; Electromyography ; Hemodynamics ; Exercise/physiology ; Isometric Contraction/physiology ; Regional Blood Flow/physiology ; Torque
    Language English
    Publishing date 2023-04-28
    Publishing country England
    Document type Journal Article
    ISSN 1536-7290
    ISSN (online) 1536-7290
    DOI 10.1080/17461391.2023.2184724
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  8. Article ; Online: Sex differences in NIRS-derived values of reactive hyperemia persist after experimentally controlling for the ischemic vasodilatory stimulus.

    Keller, Joshua L / Traylor, Miranda K / Gray, Sylvie M / Hill, Ethan C / Weir, Joseph P

    Journal of applied physiology (Bethesda, Md. : 1985)

    2023  Volume 135, Issue 1, Page(s) 3–14

    Abstract: Men and women exhibit different near-infrared spectroscopy (NIRS) outcomes in response to vascular occlusion tests (VOT), which may be due to phenotypic characteristics or different degrees of desaturation during ischemia. The minimum skeletal muscle ... ...

    Abstract Men and women exhibit different near-infrared spectroscopy (NIRS) outcomes in response to vascular occlusion tests (VOT), which may be due to phenotypic characteristics or different degrees of desaturation during ischemia. The minimum skeletal muscle tissue oxygenation (StO
    MeSH term(s) Young Adult ; Humans ; Male ; Female ; Hyperemia ; Spectroscopy, Near-Infrared/methods ; Sex Characteristics ; Ischemia ; Vascular Diseases/metabolism ; Muscle, Skeletal/metabolism ; Microcirculation/physiology ; Oxygen Consumption/physiology
    Language English
    Publishing date 2023-05-18
    Publishing country United States
    Document type Journal Article
    ZDB-ID 219139-8
    ISSN 1522-1601 ; 0021-8987 ; 0161-7567 ; 8750-7587
    ISSN (online) 1522-1601
    ISSN 0021-8987 ; 0161-7567 ; 8750-7587
    DOI 10.1152/japplphysiol.00174.2023
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  9. Article: Acute effects of low load blood flow restricted and non restricted exercise on muscle excitation, neuromuscular efficiency, and average torque.

    Hill, Ethan C / Rivera, Paola M / Proppe, Chris E / Gonzalez Rojas, David H / Lawson, John E

    Journal of musculoskeletal & neuronal interactions

    2023  Volume 23, Issue 2, Page(s) 165–174

    Abstract: Objectives: The purpose of this investigation was to examine the acute effects of low-load blood flow restriction (LLBFR) and low-load (LL) resistance exercise on muscle excitation, neuromuscular efficiency, and average torque.: Methods: Eleven men ( ... ...

    Abstract Objectives: The purpose of this investigation was to examine the acute effects of low-load blood flow restriction (LLBFR) and low-load (LL) resistance exercise on muscle excitation, neuromuscular efficiency, and average torque.
    Methods: Eleven men (age±SD=22±3yrs) randomly performed LLBFR and LL that consisted of 30 unilateral leg extensions at 30% of one-repetition maximum while surface electromyography (sEMG) and torque were simultaneously assessed. Polynomial regression analyses and slope comparisons were performed to examine patterns of responses and rates of change.
    Results: sEMG amplitude increased for LLBFR (9 of 11) and LL (8 of 11) and between composite responses (R
    Conclusion: LLBFR elicited greater fatigue-induced increases in muscle excitation and decreases in neuromuscular efficiency than LL, but neither LLBFR nor LL affected average submaximal concentric torque.
    MeSH term(s) Humans ; Male ; Electromyography ; Exercise/physiology ; Muscle, Skeletal/physiology ; Resistance Training ; Torque ; Young Adult ; Adult
    Language English
    Publishing date 2023-06-01
    Publishing country Greece
    Document type Journal Article
    ZDB-ID 2041366-X
    ISSN 1108-7161
    ISSN 1108-7161
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  10. Article ; Online: Acute Effects of Local Ischemic Hypoxia and Systemic Hypoxemia on Neuromuscular and Cognitive Function.

    Rivera, Paola M / Proppe, Christopher E / Beltran, Esther / Hill, Ethan C

    High altitude medicine & biology

    2021  Volume 23, Issue 1, Page(s) 18–25

    Abstract: Rivera, Paola M., Chris E. Proppe, Esther Beltran, and Ethan C. Hill. Acute effects of local ischemic hypoxia and systemic hypoxemia on neuromuscular and cognitive function. ...

    Abstract Rivera, Paola M., Chris E. Proppe, Esther Beltran, and Ethan C. Hill. Acute effects of local ischemic hypoxia and systemic hypoxemia on neuromuscular and cognitive function.
    MeSH term(s) Cognition ; Electromyography ; Female ; Humans ; Hypoxia ; Isometric Contraction/physiology ; Muscle, Skeletal ; Torque
    Language English
    Publishing date 2021-12-21
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2076262-8
    ISSN 1557-8682 ; 1527-0297
    ISSN (online) 1557-8682
    ISSN 1527-0297
    DOI 10.1089/ham.2021.0096
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