1,502 results on '"J. Kraemer"'
Search Results
2. Premenstrual Syndrome and Exercise: A Narrative Review
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Barbara N. Sanchez, William J. Kraemer, and Carl M. Maresh
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premenstrual syndrome ,women’s health ,exercise ,menstrual health ,Medicine ,Psychology ,BF1-990 - Abstract
Premenstrual Syndrome (PMS) is a complex physiological and psychological condition that affects a significant number of women during their reproductive years. Although the exact etiology of PMS remains unclear, its symptoms, including mood swings, bloating, irritability, and fatigue, can significantly impair the quality of life for affected individuals. The management of PMS traditionally involves pharmacological interventions; however, emerging evidence suggests that exercise may offer a valuable non-pharmacological approach to alleviate PMS symptoms. This narrative review aims to explore the proposed etiology, prevalence, and impact PMS has on women as well as examine the literature through which exercise can positively influence PMS symptoms. While the existing literature on exercise and PMS is limited and inconclusive, several studies have reported promising results. Regular exercise has been associated with a reduction in physical and psychological symptoms of PMS including pain, fatigue, mood disturbances, and water retention. Furthermore, exercise has demonstrated its potential to enhance overall well-being and mitigate the negative effects of PMS on daily functioning. Further research is warranted to elucidate the optimal exercise prescription, duration, and intensity required to maximize the benefits and improve the understanding of exercise mechanisms on PMS symptomatology.
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- 2023
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3. Useful shortcuts: Using design heuristics for consent and permission in smart home devices.
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George Chalhoub, Martin J. Kraemer, and Ivan Flechais
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- 2024
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4. 'It did not give me an option to decline': A Longitudinal Analysis of the User Experience of Security and Privacy in Smart Home Products.
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George Chalhoub, Martin J. Kraemer, Norbert Nthala, and Ivan Flechais
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- 2021
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5. Informing the Design of Privacy-Empowering Tools for the Connected Home.
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William Seymour, Martin J. Kraemer, Reuben Binns, and Max Van Kleek
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- 2020
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6. Further Exploring Communal Technology Use in Smart Homes: Social Expectations.
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Martin J. Kraemer, Ulrik Lyngs, Helena Webb, and Ivan Flechais
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- 2020
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7. The Effects of Resistance Training on Physical Fitness and Neuromotor-Cognitive Functions in Adults With Down Syndrome
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Emily M. Post, William J. Kraemer, Madison L. Kackley, Lydia K. Caldwell, Jeff S. Volek, Barbara N. Sanchez, Brian C. Focht, Robert U. Newton, Keijo Häkkinen, and Carl M. Maresh
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exercise ,cognition ,motor skill ,Trisomy 21 ,strength ,special populations ,Other systems of medicine ,RZ201-999 ,Medical technology ,R855-855.5 - Abstract
Adults with Down syndrome are an underserved population at high risk for a host of different pathologies from aging and lack of activity.PurposeTo examine the effects of a 10-week resistance training program on measures of motor behavior, cognitive function, mood, and physical fitness.MethodsParticipants (n = 11) were men and women clinically diagnosed with Down syndrome (age: 25.8 ± 6.4 years; height: 151.5 ± 8.3 cm; weight: 67.5 ± 13.0 kg; IQ: 58.3 ± 19.7 units). After familiarization of testing procedures, subjects performed The Arizona Cognitive Test Battery for Down Syndrome, TGMD-2, lower and upper body strength assessments, and body composition via DXA testing, while parental guardians completed cognitive and mood survey assessments (Cognitive Scale for Down Syndrome, Behavioral Rating Inventory of Executive Function, NiSonger Child Behavior Rating Form, Scales of Independent Behavior-Revised, Child Eating Behavior Questionnaire, Social Communication Questionnaire, and Mood and Feelings Questionnaire) at pre and post 10 weeks of periodized resistance training.ResultsSignificant (P ≤ 0.05) improvements in locomotor skills and object control skills were observed post-training. Both locomotor skills (e.g., sprint, gallop, leaping, broad jump) and object control skills (e.g., baseball catch, underhand roll, basketball dribble) were all significantly improved. Facets of cognitive performance significantly improved, specifically executive function and visuospatial working memory capacity, and frontal lobe activity. Mood disturbances significantly decrease. All aspects of physical strength and endurance were improved, i.e., leg press, bench press, sit-ups, push-ups, and chair sit-to-stand post-training. Lean tissue mass was significantly increased post-training.ConclusionThis study dramatically demonstrates that life enhancements for individuals with Down syndrome are achievable with a properly designed resistance training program.
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- 2022
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8. Exploring Communal Technology Use in the Home.
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Martin J. Kraemer, Ivan Flechais, and Helena Webb
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- 2019
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9. "It becomes more of an abstract idea, this privacy" - Informing the design for communal privacy experiences in smart homes.
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Martin J. Kraemer, George Chalhoub, Helena Webb, and Ivan Flechais
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- 2023
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10. Science and Practice of Strength Training
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Vladimir M. Zatsiorsky, William J. Kraemer, Andrew C. Fry and Vladimir M. Zatsiorsky, William J. Kraemer, Andrew C. Fry
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- 2020
11. Influence of Nutritional Ketosis Achieved through Various Methods on Plasma Concentrations of Brain Derived Neurotropic Factor
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Madison L. Kackley, Alex Buga, Chris D. Crabtree, Teryn N. Sapper, Craig A. McElroy, Brian C. Focht, William J. Kraemer, and Jeff S. Volek
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BDNF ,ketogenic diet ,BHB ,BHB salts ,exercise ,weight loss ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Brain-Derived Neurotropic Factor (BDNF) expression is decreased in conditions associated with cognitive decline as well as metabolic diseases. One potential strategy to improve metabolic health and elevate BDNF is by increasing circulating ketones. Beta-Hydroxybutyrate (BHB) stimulates BDNF expression, but the association of circulating BHB and plasma BDNF in humans has not been widely studied. Here, we present results from three studies that evaluated how various methods of inducing ketosis influenced plasma BDNF in humans. Study 1 determined BDNF responses to a single bout of high-intensity cycling after ingestion of a dose of ketone salts in a group of healthy adults who were habitually consuming either a mixed diet or a ketogenic diet. Study 2 compared how a ketogenic diet versus a mixed diet impacts BDNF levels during a 12-week resistance training program in healthy adults. Study 3 examined the effects of a controlled hypocaloric ketogenic diet, with and without daily use of a ketone-salt, on BDNF levels in overweight/obese adults. We found that (1) fasting plasma BDNF concentrations were lower in keto-adapted versus non keto-adapted individuals, (2) intense cycling exercise was a strong stimulus to rapidly increase plasma BDNF independent of ketosis, and (3) clinically significant weight loss was a strong stimulus to decrease fasting plasma BDNF independent of diet composition or level of ketosis. These results highlight the plasticity of plasma BDNF in response to lifestyle factors but does not support a strong association with temporally matched BHB concentrations.
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- 2022
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12. Trunk Muscle Strength After Lumbar Spine Fusion: A 12-Month Follow-up
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Outi Elina Ilves, Marko Henrik Neva, Keijo Häkkinen, Joost Dekker, William J. Kraemer, Sami Tarnanen, Kati Kyrölä, Jari Ylinen, Kirsi Piitulainen, Salme Järvenpää, Tiina Kaistila, and Arja Häkkinen
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Spine ,Muscle strength ,Isometric strength ,Spinal fusion ,Spine surgery ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Objective The aim of this study was to investigate changes in trunk muscle strength 12 months after lumbar spine fusion (LSF) compared to preoperative strength. Methods A total of 194 patients (mean±standard deviation [SD] age, 61±21 years) who underwent LSF participated in this prospective longitudinal study. Physical measurements of the participants were made before surgery and 12 months postoperatively. Isometric trunk extension and flexion strength was measured using a strain-gauge dynamometer in the standing position. Strength changes were calculated. Regression analysis was performed to explore which factors predicted strength levels at 12 months postoperatively. Results The preoperative mean±SD extension strength was 205±144 N, which increased to 258±142 N (p
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- 2019
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13. Fasting and diurnal blood ketonemia and glycemia responses to a six-week, energy-controlled ketogenic diet, supplemented with racemic R/S-BHB salts
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Alex Buga, Madison L. Kackley, Christopher D. Crabtree, Teryn N. Bedell, Bradley T. Robinson, Justen T. Stoner, Drew D. Decker, Parker N. Hyde, Rich A. LaFountain, Milene L. Brownlow, Annalouise O'Connor, Deepa Krishnan, Craig A. McElroy, William J. Kraemer, and Jeff S. Volek
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Nutrition and Dietetics ,Endocrinology, Diabetes and Metabolism - Published
- 2023
14. The Effects of a 6-Week Controlled, Hypocaloric Ketogenic Diet, With and Without Exogenous Ketone Salts, on Body Composition Responses
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Alex Buga, Madison L. Kackley, Christopher D. Crabtree, Teryn N. Sapper, Lauren Mccabe, Brandon Fell, Rich A. LaFountain, Parker N. Hyde, Emily R. Martini, Jessica Bowman, Yue Pan, Debbie Scandling, Milene L. Brownlow, Annalouise O'Connor, Orlando P. Simonetti, William J. Kraemer, and Jeff S. Volek
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ketogenic diet ,obesity ,exogenous ketones ,body composition ,advanced imaging ,Nutrition. Foods and food supply ,TX341-641 - Abstract
Background: Ketogenic diets (KDs) that elevate beta-hydroxybutyrate (BHB) promote weight and fat loss. Exogenous ketones, such as ketone salts (KS), also elevate BHB concentrations with the potential to protect against muscle loss during caloric restriction. Whether augmenting ketosis with KS impacts body composition responses to a well-formulated KD remains unknown.Purpose: To explore the effects of energy-matched, hypocaloric KD feeding (1.0 mM capillary BHB) throughout the study (p < 0.001), with higher fasting concentrations observed in KD + KS than KD + PL for the first 2 weeks (p < 0.05). There were decreases in body mass, whole body fat and lean mass, mid-thigh muscle cross-sectional area, and both visceral and subcutaneous adipose tissues (p < 0.001), but no group differences between the two KDs or with the LFD. Urine nitrogen excretion was significantly higher in KD + PL than LFD (p < 0.01) and trended higher in KD + PL compared to KD + KS (p = 0.076), whereas the nitrogen excretion during KD + KS was similar to LFD (p > 0.05).Conclusion: Energy-matched hypocaloric ketogenic diets favorably affected body composition but were not further impacted by administration of an exogenous BHB-salt that augmented ketosis. The trend for less nitrogen loss with the BHB-salt, if manifested over a longer period of time, may contribute to preserved lean mass.
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- 2021
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15. The Good, the Right, and the Decent: Ethical Dispositions, the Moral Viewpoint, and Just Pedagogy
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Don J. Kraemer
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Whereas composition studies tends to use ethics and morality interchangeably, these terms may work better when explicitly distinguished, rearticulated as a topic, and kept in heuristic conflict. The more the tension between them is exploited, the closer our approach to a pedagogy not so much ethical as just.
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- 2017
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16. Growth Hormone and Insulin-like Growth Factor-I Molecular Weight Isoform Responses to Resistance Exercise Are Sex-Dependent
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Joseph R. Pierce, Brian J. Martin, Kevin R. Rarick, Joseph A. Alemany, Jeffery S. Staab, William J. Kraemer, Wesley C. Hymer, and Bradley C. Nindl
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exercise endocrinology ,sex differences ,HPLC ,fractionation ,molecular weight variants ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Purpose: To determine if acute resistance exercise-induced increases in growth hormone (GH) and insulin-like growth factor-I (IGF-I) were differentially responsive for one or more molecular weight (MW) isoforms and if these responses were sex-dependent.Methods: College-aged men (n = 10) and women (n = 10) performed an acute resistance exercise test (ARET; 6 sets, 10 repetition maximum (10-RM) squat, 2-min inter-set rest). Serum aliquots from blood drawn Pre-, Mid-, and Post-ARET (0, +15, and +30-min post) were processed using High Performance Liquid Chromatography (HPLC) fractionation and pooled into 3 MW fractions (Fr.A: >60; Fr.B: 30–60; Fr.C: Fr.A > Fr.B, p ≤ 0.03). Sex × time interactions indicated that women experienced earlier and augmented increases in all serum GH MW isoform fraction pools (p < 0.05); however, men demonstrated delayed and sustained GH elevations (p < 0.01) in all fractions through +30-min of recovery. Similarly, we observed a sex-independent hierarchy among IGF-I MW fraction pools (Fr.A > Fr.B > Fr.C, p ≤ 0.01). Furthermore, we observed increases in IGF-I Fr. A (ternary complexes) in men only (p ≤ 0.05), and increases in Fr.C (free/unbound IGF-I) in women only (p ≤ 0.05) vs. baseline, respectively.Conclusions: These data indicate that the processing of GH and IGF-I isoforms from the somatotrophs and hepatocytes are differential in their response to strenuous resistance exercise and reflect both temporal and sex-related differences.
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- 2020
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17. Constitutive and Stress-Induced Psychomotor Cortical Responses to Compound K Supplementation
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Shawn D. Flanagan, Felix Proessl, Courtenay Dunn-Lewis, Maria C. Canino, Adam J. Sterczala, Chris Connaboy, William H. DuPont, Lydia K. Caldwell, and William J. Kraemer
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ginsenoside ,cortical activity ,EEG ,event-related potentials ,source localization ,exercise ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Isolated ginsenoside metabolites such as Compound K (CK) are of increasing interest to consumer and clinical populations as safe and non-pharmacological means to enhance psychomotor performance constitutively and in response to physical or cognitive stress. Nevertheless, the influence of CK on behavioral performance and EEG measures of cortical activity in humans is undetermined. In this double-blinded, placebo-controlled, counterbalanced within-group study, dose-dependent responses to CK (placebo, 160 and 960 mg) were assessed after 2 weeks of supplementation in nineteen healthy men and women (age: 39.9 ± 7.9 year, height 170.2 ± 8.6 cm, weight 79.7 ± 11.9 kg). Performance on upper- and lower-body choice reaction tests (CRTs) was tested before and after intense lower-body anaerobic exercise. Treatment- and stress-related changes in brain activity were measured with high-density EEG based on event-related potentials, oscillations, and source activity. Upper- (−12.3 ± 3.5 ms, p = 0.002) and lower-body (−12.3 ± 4.9 ms, p = 0.021) response times improved after exercise, with no difference between treatments (upper: p = 0.354; lower: p = 0.926). Analysis of cortical activity in sensor and source space revealed global increases in cortical arousal after exercise. CK increased activity in cortical regions responsible for sustained attention and mitigated exercise-induced increases in arousal. Responses to exercise varied depending on task, but CK appeared to reduce sensory interference from lower-body exercise during an upper-body CRT and improve the general maintenance of task-relevant sensory processes.
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- 2020
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18. Growth Hormone(s), Testosterone, Insulin-Like Growth Factors, and Cortisol: Roles and Integration for Cellular Development and Growth With Exercise
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William J. Kraemer, Nicholas A. Ratamess, Wesley C. Hymer, Bradley C. Nindl, and Maren S. Fragala
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anabolic ,catabolic ,protein synthesis ,skeletal muscle ,endocrine ,glucocorticoid ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Hormones are largely responsible for the integrated communication of several physiological systems responsible for modulating cellular growth and development. Although the specific hormonal influence must be considered within the context of the entire endocrine system and its relationship with other physiological systems, three key hormones are considered the “anabolic giants” in cellular growth and repair: testosterone, the growth hormone superfamily, and the insulin-like growth factor (IGF) superfamily. In addition to these anabolic hormones, glucocorticoids, mainly cortisol must also be considered because of their profound opposing influence on human skeletal muscle anabolism in many instances. This review presents emerging research on: (1) Testosterone signaling pathways, responses, and adaptations to resistance training; (2) Growth hormone: presents new complexity with exercise stress; (3) Current perspectives on IGF-I and physiological adaptations and complexity these hormones as related to training; and (4) Glucocorticoid roles in integrated communication for anabolic/catabolic signaling. Specifically, the review describes (1) Testosterone as the primary anabolic hormone, with an anabolic influence largely dictated primarily by genomic and possible non-genomic signaling, satellite cell activation, interaction with other anabolic signaling pathways, upregulation or downregulation of the androgen receptor, and potential roles in co-activators and transcriptional activity; (2) Differential influences of growth hormones depending on the “type” of the hormone being assayed and the magnitude of the physiological stress; (3) The exquisite regulation of IGF-1 by a family of binding proteins (IGFBPs 1–6), which can either stimulate or inhibit biological action depending on binding; and (4) Circadian patterning and newly discovered variants of glucocorticoid isoforms largely dictating glucocorticoid sensitivity and catabolic, muscle sparing, or pathological influence. The downstream integrated anabolic and catabolic mechanisms of these hormones not only affect the ability of skeletal muscle to generate force; they also have implications for pharmaceutical treatments, aging, and prevalent chronic conditions such as metabolic syndrome, insulin resistance, and hypertension. Thus, advances in our understanding of hormones that impact anabolic: catabolic processes have relevance for athletes and the general population, alike.
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- 2020
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19. Plates
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C. J. Kraemer Jr.
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- 2015
20. Minor Documents 97-195
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C. J. Kraemer Jr.
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- 2015
21. Note on the Method of Publication
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C. J. Kraemer Jr.
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- 2015
22. Documents 14-96
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C. J. Kraemer Jr.
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- 2015
23. Indices
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C. J. Kraemer Jr.
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- 2015
24. Texts
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C. J. Kraemer Jr.
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- 2015
25. Table of Papyri
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C. J. Kraemer Jr.
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- 2015
26. List of Abbreviations
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C. J. Kraemer Jr.
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- 2015
27. List of Plates
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C. J. Kraemer Jr.
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- 2015
28. Contents
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C. J. Kraemer Jr.
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- 2015
29. Title Page, Copyright
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C. J. Kraemer Jr.
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- 2015
30. The Associations between Asymmetric Handgrip Strength and Chronic Disease Status in American Adults: Results from the National Health and Nutrition Examination Survey
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Lukus Klawitter, Adam Bradley, Kyle J. Hackney, Grant R. Tomkinson, Bryan K. Christensen, William J. Kraemer, and Ryan McGrath
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comorbidity ,chronic disease ,epidemiologic research design ,muscle strength ,screening ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
This study examined the associations between asymmetric handgrip strength (HGS) and multimorbidity in American adults. Secondary analyses of data from persons aged at least 40 years from the 2011–2012 and 2013–2014 waves of the National Health and Nutrition Examination Survey were conducted. A handheld dynamometer collected HGS on each hand and persons with a strength imbalance >10% between hands were classified as having asymmetric HGS. Adults with the presence of ≥2 of the following conditions had multimorbidity: cardiovascular disease, chronic obstructive pulmonary disease, chronic kidney disease, asthma, arthritis, cancer, obesity, stroke, hypertension, high cholesterol, and diabetes. Of the n = 3483 participants included, n = 2700 (77.5%) had multimorbidity. A greater proportion of adults with multimorbidity had HGS asymmetry (n = 1234 (45.7%)), compared to persons living without multimorbidity (n = 314 (40.1%); p < 0.05). Relative to individuals without asymmetry, adults with asymmetric HGS had 1.31 (95% confidence interval (CI): 1.03–1.67) greater odds for multimorbidity. Moreover, persons with HGS asymmetry had 1.22 (CI: 1.04–1.44) greater odds for accumulating morbidities. Asymmetric strength, as another indicator of diminished muscle function, is linked to chronic morbidity status. Healthcare providers should recommend healthy behaviors for reducing asymmetries to improve muscle function and mitigate morbidity risk after completing asymmetry screenings.
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- 2021
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31. Preserving Privacy in Smart Homes: A Socio-Cultural Approach.
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Martin J. Kraemer
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- 2018
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32. Informing The Future of Data Protection in Smart Homes.
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Martin J. Kraemer, William Seymour, Reuben Binns, Max Van Kleek, and Ivan Flechais
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- 2019
33. Effects of Palm Stearin versus Butter in the Context of Low-Carbohydrate/High-Fat and High-Carbohydrate/Low-Fat Diets on Circulating Lipids in a Controlled Feeding Study in Healthy Humans
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Parker N. Hyde, Teryn N. Sapper, Richard A. LaFountain, Madison L. Kackley, Alex Buga, Brandon Fell, Christopher D. Crabtree, Stephen D. Phinney, Vincent J. Miller, Sarah M. King, Ronald M. Krauss, William J. Kraemer, and Jeff S. Volek
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cholesterol ,butter ,palm oil ,low-carbohydrate diet ,saturated fat ,Nutrition. Foods and food supply ,TX341-641 - Abstract
Background. Foods rich in saturated fatty acids (SFAs) have been discouraged by virtue of their cholesterol-raising potential, but this effect is modulated by the food source and background level of carbohydrate. Objective. We aimed to compare the consumption of palm stearin (PS) versus butter on circulating cholesterol responses in the setting of both a low-carbohydrate/high-fat (LC/HF) and high-carbohydrate/low-fat (HC/LF) diet in healthy subjects. We also explored effects on plasma lipoprotein particle distribution and fatty acid composition. Methods. We performed a randomized, controlled-feeding, cross-over study that compared a PS- versus a Butter-based diet in a group of normocholesterolemic, non-obese adults. A controlled canola oil-based ‘Run-In’ diet preceded the experimental PS and Butter diets. All diets were eucaloric, provided for 3-weeks, and had the same macronutrient distribution but varied in primary fat source (40% of the total fat). The same Run-In and cross-over experiments were done in two separate groups who self-selected to either a LC/HF (n = 12) or a HC/LF (n = 12) diet track. The primary outcomes were low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein (HDL)-C, triglycerides, and LDL particle distribution. Results. Compared to PS, Butter resulted in higher LDL-C in both the LC/HF (13.4%, p = 0.003) and HC/LF (10.8%, p = 0.002) groups, which was primarily attributed to large LDL I and LDL IIa particles. There were no differences between PS and Butter in HDL-C, triglycerides, or small LDL particles. Oxidized LDL was lower after PS than Butter in LC/HF (p = 0.011), but not the HC/LF group. Conclusions. These results demonstrate that Butter raises LDL-C relative to PS in healthy normocholesterolemic adults regardless of background variations in carbohydrate and fat, an effect primarily attributed to larger cholesterol-rich LDL particles.
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- 2021
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34. Need for harmonized long-term multi-lake monitoring of African Great Lakes
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Plisnier, P. D. Kayanda, R. MacIntyre, S. Obiero, K. Okello, W. Vodacek, A. Cocquyt, C. Abegaz, H. Achieng, A. Akonkwa, B. Albrecht, C. Balagizi, C. Barasa, J. Abel Bashonga, R. Bashonga Bishobibiri, A. Bootsma, H. Borges, A. V. Chavula, G. Dadi, T. De Keyzer, E. L. R. Doran, P. J. Gabagambi, N. Gatare, R. Gemmell, A. Getahun, A. Haambiya, L. H. Higgins, S. N. Hyangya, B. L. Irvine, K. Isumbisho, M. Jonasse, C. Katongo, C. Katsev, S. Keyombe, J. Kimirei, I. Kisekelwa, T. Kishe, M. Otoung A. Koding, S. Kolding, J. Kraemer, B. M. Limbu, P. Lomodei, E. Mahongo, S. B. Malala, J. Mbabazi, S. Masilya, P. M. McCandless, M. Medard, M. Migeni Ajode, Z. Mrosso, H. D. Mudakikwa, E. R. Mulimbwa, N. Mushagalusa, D. Muvundja, F. A. Nankabirwa, A. Nahimana, D. Ngatunga, B. P. Ngochera, M. Nicholson, S. Nshombo, M. Ntakimazi, G. Nyamweya, C. Ikwaput Nyeko, J. Olago, D. Olbamo, T. O'Reilly, C. M. Pasche, N. Phiri, H. Raasakka, N. Salyani, A. Sibomana, C. Silsbe, G. M. Smith, S. Sterner, R. W. Thiery, W. Tuyisenge, J. Van der Knaap, M. Van Steenberge, M. van Zwieten, P. A. M. Verheyen, E. Wakjira, M. Walakira, J. Ndeo Wembo, O. Lawrence, T. and Plisnier, P. D. Kayanda, R. MacIntyre, S. Obiero, K. Okello, W. Vodacek, A. Cocquyt, C. Abegaz, H. Achieng, A. Akonkwa, B. Albrecht, C. Balagizi, C. Barasa, J. Abel Bashonga, R. Bashonga Bishobibiri, A. Bootsma, H. Borges, A. V. Chavula, G. Dadi, T. De Keyzer, E. L. R. Doran, P. J. Gabagambi, N. Gatare, R. Gemmell, A. Getahun, A. Haambiya, L. H. Higgins, S. N. Hyangya, B. L. Irvine, K. Isumbisho, M. Jonasse, C. Katongo, C. Katsev, S. Keyombe, J. Kimirei, I. Kisekelwa, T. Kishe, M. Otoung A. Koding, S. Kolding, J. Kraemer, B. M. Limbu, P. Lomodei, E. Mahongo, S. B. Malala, J. Mbabazi, S. Masilya, P. M. McCandless, M. Medard, M. Migeni Ajode, Z. Mrosso, H. D. Mudakikwa, E. R. Mulimbwa, N. Mushagalusa, D. Muvundja, F. A. Nankabirwa, A. Nahimana, D. Ngatunga, B. P. Ngochera, M. Nicholson, S. Nshombo, M. Ntakimazi, G. Nyamweya, C. Ikwaput Nyeko, J. Olago, D. Olbamo, T. O'Reilly, C. M. Pasche, N. Phiri, H. Raasakka, N. Salyani, A. Sibomana, C. Silsbe, G. M. Smith, S. Sterner, R. W. Thiery, W. Tuyisenge, J. Van der Knaap, M. Van Steenberge, M. van Zwieten, P. A. M. Verheyen, E. Wakjira, M. Walakira, J. Ndeo Wembo, O. Lawrence, T.
- Abstract
To ensure the long-term sustainable use of African Great Lakes (AGL), and to better understand the functioning of these ecosystems, authorities, managers and scientists need regularly collected scientific data and information of key environmental indicators over multi-years to make informed decisions. Monitoring is regularly conducted at some sites across AGL; while at others sites, it is rare or conducted irregularly in response to sporadic funding or short-term projects/studies. Managers and scientists working on the AGL thus often lack critical long-term data to evaluate and gauge ongoing changes. Hence, we propose a multi-lake approach to harmonize data collection modalities for better understanding of regional and global environmental impacts on AGL. Climate variability has had strong impacts on all AGL in the recent past. Although these lakes have specific characteristics, their limnological cycles show many similarities. Because different anthropogenic pressures take place at the different AGL, harmonized multi-lake monitoring will provide comparable data to address the main drivers of concern (climate versus regional anthropogenic impact). To realize harmonized long-term multi-lake monitoring, the approach will need: (1) support of a wide community of researchers and managers; (2) political goodwill towards a common goal for such monitoring; and (3) sufficient capacity (e.g., institutional, financial, human and logistic resources) for its implementation. This paper presents an assessment of the state of monitoring the AGL and possible approaches to realize a long-term, multi-lake harmonized monitoring strategy. Key parameters are proposed. The support of national and regional authorities is necessary as each AGL crosses international boundaries.
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- 2023
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35. Repression of Human Papillomavirus Oncogene Expression under Hypoxia Is Mediated by PI3K/mTORC2/AKT Signaling
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Felicitas Bossler, Bianca J. Kuhn, Thomas Günther, Stephen J. Kraemer, Prajakta Khalkar, Svenja Adrian, Claudia Lohrey, Angela Holzer, Mitsugu Shimobayashi, Matthias Dürst, Arnulf Mayer, Frank Rösl, Adam Grundhoff, Jeroen Krijgsveld, Karin Hoppe-Seyler, and Felix Hoppe-Seyler
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AKT ,cervical cancer ,human papillomavirus ,tumor virus ,Microbiology ,QR1-502 - Abstract
ABSTRACT Hypoxia is linked to therapeutic resistance and poor clinical prognosis for many tumor entities, including human papillomavirus (HPV)-positive cancers. Notably, HPV-positive cancer cells can induce a dormant state under hypoxia, characterized by a reversible growth arrest and strong repression of viral E6/E7 oncogene expression, which could contribute to therapy resistance, immune evasion and tumor recurrence. The present work aimed to gain mechanistic insights into the pathway(s) underlying HPV oncogene repression under hypoxia. We show that E6/E7 downregulation is mediated by hypoxia-induced stimulation of AKT signaling. Ablating AKT function in hypoxic HPV-positive cancer cells by using chemical inhibitors efficiently counteracts E6/E7 repression. Isoform-specific activation or downregulation of AKT1 and AKT2 reveals that both AKT isoforms contribute to hypoxic E6/E7 repression and act in a functionally redundant manner. Hypoxic AKT activation and consecutive E6/E7 repression is dependent on the activities of the canonical upstream AKT regulators phosphoinositide 3-kinase (PI3K) and mechanistic target of rapamycin (mTOR) complex 2 (mTORC2). Hypoxic downregulation of E6/E7 occurs, at least in part, at the transcriptional level. Modulation of E6/E7 expression by the PI3K/mTORC2/AKT cascade is hypoxia specific and not observed in normoxic HPV-positive cancer cells. Quantitative proteome analyses identify additional factors as candidates to be involved in hypoxia-induced activation of the PI3K/mTORC2/AKT signaling cascade and in the AKT-dependent repression of the E6/E7 oncogenes under hypoxia. Collectively, these data uncover a functional key role of the PI3K/mTORC2/AKT signaling cascade for viral oncogene repression in hypoxic HPV-positive cancer cells and provide new insights into the poorly understood cross talk between oncogenic HPVs and their host cells under hypoxia. IMPORTANCE Oncogenic HPV types are major human carcinogens. Under hypoxia, HPV-positive cancer cells can repress the viral E6/E7 oncogenes and induce a reversible growth arrest. This response could contribute to therapy resistance, immune evasion, and tumor recurrence upon reoxygenation. Here, we uncover evidence that HPV oncogene repression is mediated by hypoxia-induced activation of canonical PI3K/mTORC2/AKT signaling. AKT-dependent downregulation of E6/E7 is only observed under hypoxia and occurs, at least in part, at the transcriptional level. Quantitative proteome analyses identify additional factors as candidates to be involved in AKT-dependent E6/E7 repression and/or hypoxic PI3K/mTORC2/AKT activation. These results connect PI3K/mTORC2/AKT signaling with HPV oncogene regulation, providing new mechanistic insights into the cross talk between oncogenic HPVs and their host cells.
- Published
- 2019
- Full Text
- View/download PDF
36. Paradox of hypercholesterolaemia in highly trained, keto-adapted athletes
- Author
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Brent C Creighton, Parker Neil Hyde, Carl M Maresh, William J Kraemer, Stephen D Phinney, and Jeff S Volek
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Medicine (General) ,R5-920 - Abstract
Objective A growing number of ultra-endurance athletes have switched to a very low-carbohydrate/high-fat eating pattern. We compared markers of cholesterol and the lipoprotein profile in a group of elite ultra-runners consuming a high-carbohydrate (HC) or low-carbohydrate (LC) diet.Methods Fasting blood was obtained from competitive male ultra-endurance runners habitually consuming a very low-carbohydrate (LC; n=10) or high-carbohydrate (HC; n=10) diet to determine blood cholesterol profile, lipoprotein particle distribution and sterol biomarkers of cholesterol balance.Results Plasma total cholesterol, low-density lipoprotein (LDL-C) and high-density lipoprotein (HDL-C) cholesterol were all significantly greater (p
- Published
- 2018
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37. Comparison of Ketogenic Diets with and without Ketone Salts versus a Low-Fat Diet: Liver Fat Responses in Overweight Adults
- Author
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Christopher D. Crabtree, Madison L. Kackley, Alexandru Buga, Brandon Fell, Richard A. LaFountain, Parker N. Hyde, Teryn N. Sapper, William J. Kraemer, Debbie Scandling, Orlando P. Simonetti, and Jeff S. Volek
- Subjects
NAFLD ,liver fat ,low carbohydrate ,ketogenic diet ,exogenous ketones ,Nutrition. Foods and food supply ,TX341-641 - Abstract
Ketogenic diets (KDs) often contain high levels of saturated fat, which may increase liver fat, but the lower carbohydrate intake may have the opposite effect. Using a controlled feeding design, we compared liver fat responses to a hypocaloric KD with a placebo (PL) versus an energy-matched low-fat diet (LFD) in overweight adults. We also examined the added effect of a ketone supplement (KS). Overweight adults were randomized to a 6-week KD (KD + PL) or a KD with KS (KD + KS); an LFD group was recruited separately. All diets were estimated to provide 75% of energy expenditure. Weight loss was similar between groups (p > 0.05). Liver fat assessed by magnetic resonance imaging decreased after 6 week (p = 0.004) with no group differences (p > 0.05). A subset with nonalcoholic fatty liver disease (NAFLD) (liver fat > 5%, n = 12) showed a greater reduction in liver fat, but no group differences. In KD participants with NAFLD, 92% of the variability in change in liver fat was explained by baseline liver fat (p < 0.001). A short-term hypocaloric KD high in saturated fat does not adversely impact liver health and is not impacted by exogenous ketones. Hypocaloric low-fat and KDs can both be used in the short-term to significantly reduce liver fat in individuals with NAFLD.
- Published
- 2021
- Full Text
- View/download PDF
38. Acute Floatation-REST Improves Perceived Recovery After a High-Intensity Resistance Exercise Stress in Trained Men
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Lydia K, Caldwell, William J, Kraemer, Emily M, Post, Jeff S, Volek, Brian C, Focht, Robert U, Newton, Keijo, Häkkinen, and Carl M, Maresh
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Adult ,Male ,väsymys ,palautuminen ,Resistance Training ,lihakset ,Physical Therapy, Sports Therapy and Rehabilitation ,Myalgia ,float ,Young Adult ,kellunta ,muscle damage ,testosterone ,Humans ,soreness ,fatigue ,Orthopedics and Sports Medicine ,voimaharjoittelu ,testosteroni ,Muscle, Skeletal ,Exercise ,Fatigue - Abstract
The aim of the present investigation was to determine whether a 1-h floatation-restricted environmental stimulation therapy (floatation-REST) session could augment recovery from high-intensity resistance exercise (6 × 10 back squats, 2-min rest) known to induce significant metabolic, adrenergic, and mechanical stress.Eleven healthy resistance-trained males (age, 22.5 ± 2.3 yr; height, 176.4 ± 6.0 cm; weight, 85.7 ± 6.2 kg; back squat one-repetition maximum, 153.1 ± 20.1 kg; strength-to-weight ratio, 1.8 ± 0.2) completed the within-subject, crossover controlled study design. Participants completed two exercise testing blocks separated by a 2-wk washout. In one block, the high-intensity resistance exercise protocol was followed by a 1-h floatation-REST session, whereas recovery in the alternate block consisted of a passive sensory-stimulating control. Markers of metabolic stress, neuroendocrine signaling, structural damage, inflammation, and perceptions of soreness, mood state, and fatigue were assessed over a 48-h recovery window.Floatation-REST significantly attenuated muscle soreness across recovery ( P = 0.035) with greatest treatment difference immediately after the intervention ( P = 0.002, effect size (ES) = 1.3). Significant differences in norepinephrine ( P = 0.028, ES = 0.81) and testosterone ( P = 0.028, ES = 0.81) immediately after treatment revealed the modification of neuroendocrine signaling pathways, which were accompanied by greater improvements in mood disturbance ( P = 0.029, ES = 0.81) and fatigue ( P = 0.001, ES = 1.04).Because no adverse effects and significant and meaningful benefits were observed, floatation-REST may prove a valuable intervention for managing soreness and enhancing performance readiness after exercise.
- Published
- 2022
39. Choice of Resistance Used in an Exercise: Simple to Complex Interactions
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William J. Kraemer and Mike Nitka
- Published
- 2022
40. To Each According to Their Needs: Readerly Desire in Rhetorical Poetics and in Jesus' Son
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Don J. Kraemer
- Subjects
General Earth and Planetary Sciences ,General Environmental Science - Published
- 2022
41. Effects of clenbuterol enantiomers on growth of young male rats
- Author
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Takashi Kitaura, Shoki Suzuki, and William J. Kraemer
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β2-adrenergic agonists ,clenbuterol enantiomer ,striated muscle ,femur ,tibia ,Sports medicine ,RC1200-1245 ,Physiology ,QP1-981 - Abstract
Clenbuterol (CB) is one of the β2-adrenergic receptor agonists with powerful muscle anabolic and lipolytic effects, and is prohibited as a doping drug for athletes. However, it is one of the candidate countermeasures for aging-related diseases. Previously we reported that CB induced muscular hypertrophy, but inhibited the longitudinal growth of bones in young male rats. However, the mechanism of the inhibitory effect on bone growth is not yet clear. CB is manufactured as a 1:1 racemic mixture of 2 isomers of (-)-R and (+)-S enantiomers, and only the (-)-R enantiomer may have pharmacological activity. We examined the effects of two CB enantiomers, (+)-S-CB and (-)-R-CB, on growth of striated muscle and bone in young male rats. Eighteen male Sprague-Dawley rats (8-wk-old) were randomly assigned to a control (CONT, n = 6) and two CB enantiomers groups ((+)-S-CLEB: n=6, (-)-R-CLEB: n=6). Each CB enantiomer of 2 mg/kg body weight was daily administered subcutaneously for 2 weeks. After treatment, heart and the slow-twitch soleus (SOL) and fast-twitch extensor digitorum longus (EDL) muscles and bones were analyzed. The muscle wet weights of SOL and EDL muscles significantly increased in (+)-S-CLEB (HEART: +28%, SOL: +25%, EDL: +28%) and (-)-R-CLEB (HEART: +27%, SOL: +29%, EDL: +35%). Both (+)-S-CB and (-)-R-CB induced striated muscle hypertrophy (heart, SOL, and EDL). Concerning bones, (+)-S-CB induced decreased tibia length (-1.2%) and decreased femur BMD (-5.8%), and (-)-R-CB induced decreased femur BMD (-8.2%). These results show that (+)-S-CB and (-)-R-CB might work differently at times.
- Published
- 2015
- Full Text
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42. Dudrick Research Symposium: Expanding the boundaries of cancer care through nutrition support
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Jose M. Pimiento and William J. Kraemer
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education.field_of_study ,Nutrition and Dietetics ,Coronavirus disease 2019 (COVID-19) ,media_common.quotation_subject ,Cancer chemoprevention ,education ,Population ,Medicine (miscellaneous) ,Tribute ,Cancer ,medicine.disease ,Nutrition science ,humanities ,Presentation ,Nursing ,Honor ,medicine ,Sociology ,media_common - Abstract
The 2020 Dudrick Research Symposium, entitled "Expanding the Boundaries of Cancer Care Through Nutritional Support" was held on March 30, 2020, at the American Society for Parenteral and Enteral Nutrition (ASPEN), 2020 Nutrition Science & Practice Conference, it was scheduled to take place in Tampa, Florida but had to be held virtually due to the COVID-19 pandemic. The Dudrick Symposium honors the many pivotal and innovative contributions to the development and advancement of parenteral nutrition (PN) made by the late Dr. Stanley J. Dudrick, physician scientist, academic leader, and a founding member of ASPEN. This year, in addition to honor his legacy, we honored his life as we had to endure his loss in the beginning of 2020. As the 2019 recipient of the Dudrick Research Scholar Award, Dr. Jose M Pimiento organized and chaired the symposium. The presentations focused on discussing the history and the present and the future frontiers in the overlapping fields of nutritional support and cancer care. The late Dr. John Daly opened the presentation with a very moving tribute to Dr. Dudrick's life and then spoke about the impact of nutritional support on surgical care and oncologic outcomes for cancer patients. Dr. Pimiento discussed the role of nutraceuticals for cancer chemoprevention, focusing on discussing the level one clinical evidence surrounding this topic. Dr. Kraemer, explored the role of exercise physiology in cancer care for optimal nutrient utilization and the overlap between targeted physical activity and nutritional support to obtain better outcomes on the cancer population. The symposium was closed by Dr. Stephen Hursting who discussed the preclinical and clinical evidence on the impact of obesity in the soaring cancer rates and its relationship with clinical outcomes. In this paper, we cover the presentations by Drs Pimiento and Kraemer. This article is protected by copyright. All rights reserved.
- Published
- 2021
43. Evidence-Based Practice in Exercise Science: The Six-Step Approach
- Author
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William E. Amonette, Kirk L. English, William J. Kraemer and William E. Amonette, Kirk L. English, William J. Kraemer
- Published
- 2016
44. Acute Effects of High-intensity Resistance Exercise on Cognitive Function
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Robert U. Newton, Scott M. Hayes, Matthew K. Beeler, William J. Kraemer, Lydia K. Caldwell, Keijo Häkkinen, John Paul V. Anders, Emily R. Martini, Jeff S. Volek, Carl M. Maresh, Emily M. Post, and William H. DuPont
- Subjects
Adult ,Male ,Elementary cognitive task ,medicine.medical_specialty ,fyysinen rasitus ,Physical Therapy, Sports Therapy and Rehabilitation ,Squat ,Audiology ,Young Adult ,03 medical and health sciences ,Cognition ,0302 clinical medicine ,Heart Rate ,Memory ,exercise stress ,Reaction Time ,medicine ,Humans ,Attention ,Orthopedics and Sports Medicine ,Lactic Acid ,Muscle Strength ,Neuropsychological assessment ,back squat ,medicine.diagnostic_test ,Muscle fatigue ,business.industry ,Resistance training ,Repeated measures design ,liikuntafysiologia ,Resistance Training ,030229 sport sciences ,kognitiiviset prosessit ,reaktiot ,automated neuropsychological assessment metrics ,Mental Recall ,GV557-1198.995 ,Sports medicine ,muscle fatigue ,voimaharjoittelu ,Analysis of variance ,business ,RC1200-1245 ,030217 neurology & neurosurgery ,Research Article ,Sports - Abstract
The purpose of the present study was to examine the influence of an acute bout of high-intensity resistance exercise on measures of cognitive function. Ten men (Mean ± SD: age = 24.4 ± 3.2 yrs; body mass = 85.7 ± 11.8 kg; height = 1.78 ± 0.08 m; 1 repetition maximum (1RM) = 139.0 ± 24.1 kg) gave informed consent and performed a high-intensity 6 sets of 10 repetitions of barbell back squat exercise at 80% 1RM with 2 minutes rest between sets. The Automated Neuropsychological Assessment Metrics (ANAM) was completed to assess various cognitive domains during the familiarization period, immediately before, and immediately after the high-intensity resistance exercise bout. The repeated measures ANOVAs for throughput scores (r·m-1) demonstrated significant mean differences for the Mathematical Processing task (MTH; p < 0.001, η2p = 0.625) where post hoc pairwise comparisons demonstrated that the post-fatigue throughput (32.0 ± 8.8 r·m-1) was significantly greater than the pre-fatigue (23.8 ± 7.4 r·m-1, p = 0.003, d = 1.01) and the familiarization throughput (26.4 ± 5.3 r·m-1, p = 0.024, d = 0.77). The Coded Substitution-Delay task also demonstrated significant mean differences (CDD; p = 0.027, η2p = 0.394) with post hoc pairwise comparisons demonstrating that the post-fatigue throughput (49.3 ± 14.4 r·m-1) was significantly less than the pre-fatigue throughput (63.2 ± 9.6 r·m-1, p = 0.011, d = 1.14). The repeated measures ANOVAs for reaction time (ms) demonstrated significant mean differences for MTH (p < 0.001, η2p = 0.624) where post hoc pairwise comparisons demonstrated that the post-fatigue reaction time (1885.2 ± 582.8 ms) was significantly less than the pre-fatigue (2518.2 ± 884.8 ms, p = 0.005, d = 0.85) and familiarization (2253.7 ± 567.6 ms, p = 0.009, d = 0.64) reaction times. The Go/No-Go task demonstrated significant mean differences (GNG; p = 0.031, η2p = 0.320) with post hoc pairwise comparisons demonstrating that the post-fatigue (285.9 ± 16.3 ms) was significantly less than the pre-fatigue (298.5 ± 12.1 ms, p = 0.006, d = 0.88) reaction times. High-intensity resistance exercise may elicit domain-specific influences on cognitive function, characterized by the facilitation of simple cognitive tasks and impairments of complex cognitive tasks. Key points High-intensity squat resistance exercise may elicit domain-specific influences on cognitive function. Tasks associated with information processing and response inhibition was exhibited improvement for simple cognitive tasks. Complex cognitive associated with memory and recall exhibited decrements and impairments following the high-intensity back squat protocol. Understanding changes in cognition under extreme physical stress is important for interpretation of physiological influences.
- Published
- 2021
45. Anabolic-Androgenic Steroid Use in Sports, Health, and Society
- Author
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Nicholas A. Ratamess, Shalender Bhasin, Michele LaBotz, Disa L. Hatfield, Jay R. Hoffman, William J. Kraemer, and Stuart M. Phillips
- Subjects
education.field_of_study ,medicine.medical_specialty ,biology ,Sports medicine ,Athletes ,Population ,Physical Therapy, Sports Therapy and Rehabilitation ,Competitive athletes ,Testosterone (patch) ,biology.organism_classification ,Steroid use ,medicine ,Orthopedics and Sports Medicine ,Psychology ,education ,Psychiatry - Abstract
This consensus statement is an update of the 1987 American College of Sports Medicine (ACSM) position stand on the use of anabolic-androgenic steroids (AAS). Substantial data have been collected since the previous position stand, and AAS use patterns have changed significantly. The ACSM acknowledges that lawful and ethical therapeutic use of AAS is now an accepted mainstream treatment for several clinical disorders; however, there is increased recognition that AAS are commonly used illicitly to enhance performance and appearance in several segments of the population, including competitive athletes. The illicit use of AAS by competitive athletes is contrary to the rules and ethics of many sport governing bodies. Thus, the ACSM deplores the illicit use of AAS for athletic and recreational purposes. This consensus statement provides a brief history of AAS use, an update on the science of how we now understand AAS to be working metabolically/biochemically, potential side effects, the prevalence of use among athletes, and the use of AAS in clinical scenarios.
- Published
- 2021
46. Importance of an In-Season Strength Training Program: A Reminder to Sport Coaches
- Author
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William J. Kraemer and Mike Nitka
- Published
- 2022
47. Atrial strain in patients with pulmonary arterial hypertension associated with congenital heart disease
- Author
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P. Moceri and J. Kraemer
- Subjects
Cardiology and Cardiovascular Medicine - Published
- 2023
48. Princeton Legacy Library: Non-Literary Papyri
- Author
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C. J. Kraemer, C. Kraemer and C. J. Kraemer, C. Kraemer
- Published
- 2015
49. Left atrial reservoir strain during acute heart failure: A prospective cohort study
- Author
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J. Bateau, J. Kraemer, D. Bertora, D. Baudouy, S.-S. Bun, F. Squara, E. Ferrari, and P. Moceri
- Subjects
Cardiology and Cardiovascular Medicine - Published
- 2023
50. Insulin-like growth factor-I biocompartmentalization across blood, interstitial fluid and muscle, before and after 3 months of chronic resistance exercise
- Author
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Adam J. Sterczala, Joseph R. Pierce, Brian R. Barnes, Maria L. Urso, Ronald W. Matheny, Dennis E. Scofield, Shawn D. Flanagan, Carl M. Maresh, Edward J. Zambraski, William J. Kraemer, and Bradley C. Nindl
- Subjects
Male ,Young Adult ,Physiology ,Physiology (medical) ,Humans ,Extracellular Fluid ,Female ,Resistance Training ,Insulin-Like Growth Factor I ,Muscle, Skeletal ,Exercise ,Proto-Oncogene Proteins c-akt ,Research Article - Abstract
This investigation examined the influence of 12-week ballistic resistance training programs on the IGF-I system in circulation, interstitial fluid, and skeletal muscle, at rest and in response to acute exercise. Seventeen college-aged subjects (11 women/6 men; 21.7 ± 3.7 yr) completed an acute ballistic exercise bout before and after the training program. Blood samples were collected pre-, mid-, and postexercise and analyzed for serum total IGF-I, free IGF-I, and IGF binding proteins (IGFBPs) 1–4. Dialysate and interstitial free IGF-I were analyzed in vastus lateralis (VL) interstitial fluid collected pre- and postexercise via microdialysis. Pre- and postexercise VL muscle biopsies were analyzed for IGF-I protein expression, IGF-I receptor phosphorylation (p-IGF-IR), and AKT phosphorylation (p-AKT). Following training, basal serum IGF-I, free IGF-I, IGFBP-2, and IGFBP-3 decreased whereas IGFBP-1 and IGFBP-4 increased. Training reduced basal dialysate and interstitial free IGF-I but had no effect on basal skeletal muscle IGF-I, p-IGF-IR, or p-AKT. Acute exercise elicited transient changes in IGF-I system concentrations and downstream anabolic signaling both pre- and posttraining; training did not affect this acute exercise response. Posttraining, acute exercise-induced changes in dialysate/interstitial free IGF-I were strongly correlated with the changes in intramuscular IGF-I expression, p-IGF-IR, and p-AKT. The divergent influence of resistance training on circulating/interstitial and skeletal muscle IGF-I demonstrates the importance of concurrent, multiple biocompartment analysis when examining the IGF-I system. As training elicited muscle hypertrophy, these findings indicate that IGF-I’s anabolic effects on skeletal muscle are mediated by local, rather than systemic mechanisms. NEW & NOTEWORTHY In the first investigation to assess resistance training’s effects on the IGF-I system in serum, interstitial fluid, and skeletal muscle, training decreased basal circulating and interstitial IGF-I but did not alter basal intramuscular IGF-I protein activity. Posttraining, acute exercise-induced interstitial IGF-I increases were strongly correlated with intramuscular IGF-I expression and signaling. These findings highlight the importance of multibiocompartment measurement when analyzing IGF-I and suggest that IGF-I’s role in hypertrophic adaptations is locally mediated.
- Published
- 2022
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