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Angelidi AM, Stefanakis K, Chou SH, Valenzuela-Vallejo L, Dipla K, Boutari C, Ntoskas K, Tokmakidis P, Kokkinos A, Goulis DG, Papadaki HA, Mantzoros CS. Relative Energy Deficiency in Sport (REDs): Endocrine Manifestations, Pathophysiology and Treatments. Endocr Rev 2024; 45:676-708. [PMID: 38488566 DOI: 10.1210/endrev/bnae011] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2023] [Indexed: 09/18/2024]
Abstract
Research on lean, energy-deficient athletic and military cohorts has broadened the concept of the Female Athlete Triad into the Relative Energy Deficiency in Sport (REDs) syndrome. REDs represents a spectrum of abnormalities induced by low energy availability (LEA), which serves as the underlying cause of all symptoms described within the REDs concept, affecting exercising populations of either biological sex. Both short- and long-term LEA, in conjunction with other moderating factors, may produce a multitude of maladaptive changes that impair various physiological systems and adversely affect health, well-being, and sport performance. Consequently, the comprehensive definition of REDs encompasses a broad spectrum of physiological sequelae and adverse clinical outcomes related to LEA, such as neuroendocrine, bone, immune, and hematological effects, ultimately resulting in compromised health and performance. In this review, we discuss the pathophysiology of REDs and associated disorders. We briefly examine current treatment recommendations for REDs, primarily focusing on nonpharmacological, behavioral, and lifestyle modifications that target its underlying cause-energy deficit. We also discuss treatment approaches aimed at managing symptoms, such as menstrual dysfunction and bone stress injuries, and explore potential novel treatments that target the underlying physiology, emphasizing the roles of leptin and the activin-follistatin-inhibin axis, the roles of which remain to be fully elucidated, in the pathophysiology and management of REDs. In the near future, novel therapies leveraging our emerging understanding of molecules and physiological axes underlying energy availability or lack thereof may restore LEA-related abnormalities, thus preventing and/or treating REDs-related health complications, such as stress fractures, and improving performance.
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Affiliation(s)
- Angeliki M Angelidi
- Department of Medicine, Boston VA Healthcare System, Boston, MA 02115, USA
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Konstantinos Stefanakis
- Department of Medicine, Boston VA Healthcare System, Boston, MA 02115, USA
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- First Propaedeutic Department of Internal Medicine, Laiko General Hospital, Medical School, National and Kapodistrian University of Athens, Athens 11527, Greece
- Department of Internal Medicine, 251 Air Force General Hospital, Athens 11525, Greece
| | - Sharon H Chou
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital (BWH), Harvard Medical School, Boston, MA 02115, USA
| | - Laura Valenzuela-Vallejo
- Department of Medicine, Boston VA Healthcare System, Boston, MA 02115, USA
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Konstantina Dipla
- Exercise Physiology and Biochemistry Laboratory, Department of Sports Science at Serres, Aristotle University of Thessaloniki, Serres 62100, Greece
| | - Chrysoula Boutari
- Second Propaedeutic Department of Internal Medicine, Hippokration Hospital, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki 54642, Greece
| | - Konstantinos Ntoskas
- Department of Internal Medicine, 251 Air Force General Hospital, Athens 11525, Greece
| | - Panagiotis Tokmakidis
- First Propaedeutic Department of Internal Medicine, Laiko General Hospital, Medical School, National and Kapodistrian University of Athens, Athens 11527, Greece
- Department of Internal Medicine, 251 Air Force General Hospital, Athens 11525, Greece
| | - Alexander Kokkinos
- First Propaedeutic Department of Internal Medicine, Laiko General Hospital, Medical School, National and Kapodistrian University of Athens, Athens 11527, Greece
| | - Dimitrios G Goulis
- Unit of Reproductive Endocrinology, First Department of Obstetrics and Gynecology, Medical School, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Helen A Papadaki
- Department of Hematology, University Hospital of Heraklion, School of Medicine, University of Crete, Heraklion 71500, Greece
| | - Christos S Mantzoros
- Department of Medicine, Boston VA Healthcare System, Boston, MA 02115, USA
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital (BWH), Harvard Medical School, Boston, MA 02115, USA
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Talarico Neto T, Magraner JM, Hahns Júnior HC, Ferreira L, Martinelli Júnior CE, Tourinho Filho H. Biphasic Kinetics of IGF-I and IGFBP-3 in Response to Military Field Training in Brazilian Air Force Recruits. Mil Med 2024; 189:e1417-e1422. [PMID: 38687564 PMCID: PMC11221556 DOI: 10.1093/milmed/usae097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 10/10/2023] [Accepted: 03/14/2024] [Indexed: 05/02/2024] Open
Abstract
INTRODUCTION Insulin-like growth factor type I (IGF-I) has gained considerable notoriety in military training, primarily because it is responsible for energy deficits and sensitive to an inadequate protein intake, which are situations that are commonly experienced in specific military operations. Therefore, this study aimed to assess the kinetics of IGF-I and insulin-like growth factor binding protein type 3 (IGFBP-3) in a 4-day military field training exercise. MATERIALS AND METHODS The sample comprised 12 male soldiers (21.71 ± 1.64 years). Changes were assessed at 3 times: time 1-basal (control week); time 2-after specific military field training; and time 3-1 week after the specific training (control week). Changes in body composition and serum levels of IGF-I and IGFBP-3 were observed. RESULTS The main finding of this study was it verified the biphasic kinetics of both IGF-I and IGFBP-3 at the 3 times observed, that is, a significant drop from time 1 (basal-IGF-I: 189 ng/mL and IGFBP-3: 4.71 mg/L) to time 2 (immediately after military training-IGF-I: 162 ng/mL and IGFBP-3: 4.08 mg/L) and a subsequent recovery of these markers, with a significant increase from time 2 (immediately after military training) to time 3 (a week after military training-IGF-I: 199 ng/mL and IGFBP-3: 4.96 mg/L). CONCLUSIONS It can be concluded that IGF-I and IGFBP-3 levels respond quickly to the stimuli caused by military training, especially after specific field training. However, the same markers quickly return to their basal values after this type of training finishes, simply by following the daily routine of the battalion in the control weeks, with no specific intervention being necessary.
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Affiliation(s)
- Thomaz Talarico Neto
- School of Physical Education and Sport of Ribeirao Preto-EEFERP/USP, University of Sao Paulo-USP; 3900 Bandeirantes Avenue-Campus da USP, Ribeirão Preto, SP 14049-900, Brazil
| | - José Maurício Magraner
- Brazilian Air Force Academy-AFA, Pirassununga, SP 13643-000, Brazil
- School of Physical Education-FEF/UNICAMP, State University of Campinas; Cidade Universitária Zeferino Vaz-Barão Geraldo, Campinas, SP 13083-970, Brazil
| | - Higino Carlos Hahns Júnior
- School of Physical Education and Sport of Ribeirao Preto-EEFERP/USP, University of Sao Paulo-USP; 3900 Bandeirantes Avenue-Campus da USP, Ribeirão Preto, SP 14049-900, Brazil
| | | | - Carlos Eduardo Martinelli Júnior
- Faculty of Medicine of Ribeirão Preto, University of Sao Paulo-USP; 3900 Bandeirantes Avenue-Campus da USP, Ribeirão Preto, SP 14049-900, Brazil
| | - Hugo Tourinho Filho
- School of Physical Education and Sport of Ribeirao Preto-EEFERP/USP, University of Sao Paulo-USP; 3900 Bandeirantes Avenue-Campus da USP, Ribeirão Preto, SP 14049-900, Brazil
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Roberts BM, Staab JS, Caldwell AR, Sczuroski CE, Staab JE, Lutz LJ, Reynoso M, Geddis AV, Taylor KM, Guerriere KI, Walker LA, Hughes JM, Foulis SA. Sex Does Not Affect Changes in Body Composition and Insulin-Like Growth Factor-I During US Army Basic Combat Training. J Strength Cond Res 2024; 38:e304-e309. [PMID: 38320231 DOI: 10.1519/jsc.0000000000004735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2024]
Abstract
ABSTRACT Roberts, BM, Staab, JS, Caldwell, AR, Sczuroski, CE, Staab, JE, Lutz, LJ, Reynoso, M, Geddis, AV, Taylor, KM, Guerriere, KI, Walker, LA, Hughes, JM, and Foulis, SA. Sex does not affect changes in body composition and insulin-like growth factor-I during US Army basic combat training. J Strength Cond Res 38(6): e304-e309, 2024-Insulin-like growth factor 1 (IGF-I) has been implicated as a biomarker of health and body composition. However, whether changes in body composition are associated with changes in IGF-I is unclear. Therefore, we examined the relationship between body composition changes (i.e., fat mass and lean mass) and total serum IGF-I levels in a large cohort of young men ( n = 809) and women ( n = 397) attending US Army basic combat training (BCT). We measured body composition using dual energy x-ray absorptiometry and total serum IGF-I levels during week 1 and week 9 of BCT. We found that pre-BCT lean mass ( r = 0.0504, p = 0.082) and fat mass ( r = 0.0458, p = 0.082) were not associated with pre-BCT IGF-I. Body mass, body mass index, body fat percentage, and fat mass decreased, and lean mass increased during BCT (all p < 0.001). Mean (± SD ) IGF-I increased from pre-BCT (176 ± 50 ng·ml -1 ) to post-BCT (200 ± 50 ng·ml -1 , p < 0.001). Inspection of the partial correlations indicated that even when considering the unique contributions of other variables, increases in IGF-I during BCT were associated with both increased lean mass ( r = 0.0769, p = 0.023) and increased fat mass ( r = 0.1055, p < 0.001) with no sex differences. Taken together, our data suggest that although changes in IGF-I weakly correlated with changes in body composition, IGF-I, in isolation, is not an adequate biomarker for predicting changes in body composition during BCT in US Army trainees.
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Affiliation(s)
- Brandon M Roberts
- Military Performance Division, US Army Research of Environmental Medicine, Natick, Massachusetts
| | - Jeffery S Staab
- Military Performance Division, US Army Research of Environmental Medicine, Natick, Massachusetts
| | - Aaron R Caldwell
- Thermal & Mountain Medicine Division, US Army Research of Environmental Medicine, Natick, Massachusetts
| | - Cara E Sczuroski
- Military Performance Division, US Army Research of Environmental Medicine, Natick, Massachusetts
| | - Janet E Staab
- Military Performance Division, US Army Research of Environmental Medicine, Natick, Massachusetts
| | - Laura J Lutz
- Military Performance Division, US Army Research of Environmental Medicine, Natick, Massachusetts
| | - Marinaliz Reynoso
- Military Performance Division, US Army Research of Environmental Medicine, Natick, Massachusetts
| | - Alyssa V Geddis
- Military Performance Division, US Army Research of Environmental Medicine, Natick, Massachusetts
| | - Kathryn M Taylor
- Military Performance Division, US Army Research of Environmental Medicine, Natick, Massachusetts
| | - Katelyn I Guerriere
- Military Performance Division, US Army Research of Environmental Medicine, Natick, Massachusetts
| | - Leila A Walker
- Military Performance Division, US Army Research of Environmental Medicine, Natick, Massachusetts
| | - Julie M Hughes
- Military Performance Division, US Army Research of Environmental Medicine, Natick, Massachusetts
| | - Stephen A Foulis
- Military Performance Division, US Army Research of Environmental Medicine, Natick, Massachusetts
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Ponce T, Mainenti MRM, Barros T, Cahuê FLC, Fernanda Martins Dos Santos C, Piazera BKL, Salerno VP, Vaisman M. Biochemical and Hormone Markers in Firefighters: Effects of "Search, Rescue, and Survival Training" and Its Recovery. J Strength Cond Res 2024; 38:e189-e201. [PMID: 38266224 DOI: 10.1519/jsc.0000000000004695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2024]
Abstract
ABSTRACT Ponce, T, Mainenti, MRM, de Barros, T, Cahuê, FLC, Fernanda, C, Piazera, BKL, Salerno, VP, and Vaisman, M. Biochemical and hormone markers in firefighters: effects of "search, rescue, and survival training" and its recovery. J Strength Cond Res 38(4): e189-e201, 2024-This study aimed to evaluate the hormonal and biochemical responses in military firefighter cadets to a search, rescue, and survival training (SRST) course. Forty-three male volunteers participated in the SRST over 15 days consisting of intense physical effort, sleep deprivation, and a survival period with food deprivation. At 3 timepoints (baseline, SRST, and 1 week rec), subjects submitted to blood collections, body composition examinations, physical performance evaluations, and cognitive function tests. After the SRST, lower values were registered for testosterone (764.0; 565.1-895.0 to 180.6; 133.6-253.5 ng·dl -1 ) and insulin-like growth factor-1 (IGF-1) (217; 180-238 to 116; 102-143 ng·ml -1 ). Increases were observed for cortisol (9.7; 8.2-11.7 to 18.3; 16.5-21,2 μg·dl -1 ), growth hormone (GH) (0.11; 0.06-0.20 to 2.17; 1.4-3.4 ng·ml -1 ), CP, GSSG, lactate dehydrogenase, alanine aminotransferase, and aspartate aminotransferase as well as the antioxidant response of superoxide dismutase and glutathione peroxidase. The values of gamma-glutamyl transferase were reduced. After 1 week of recovery, levels of GH, creatine kinase, GSH, and GSSG returned to baseline values ( p < 0.05). Vertical jump performance presented a regular positive correlation with testosterone (rho = 0.56 and p < 0.0001) and a strong negative correlation with cortisol (rho = -0.61 and p < 0.0001). Body fat showed a regular and positive correlation with both testosterone and IGF-1. We conclude that participation in the SRST caused significant hormonal and biochemical changes in individuals that correlated with a loss in physical performance. Importantly, the results suggest the need for longer recovery times before a return to normal military duties.
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Affiliation(s)
- Thalita Ponce
- Department of Physical Education, Dom Pedro II Military Firefighter Academy (ABMDPII), Rio de Janeiro, State of Rio de Janeiro, Brazil
- Department of Biosciences, Physical Education and Sports College of the Federal University of Rio de Janeiro (EEFD/UFRJ), State of Rio de Janeiro, Brazil
- Department of Internal Medicine-Endocrinology, Federal University of Rio de Janeiro (FM-UFRJ), State of Rio de Janeiro, Brazil; and
| | | | - Thiago Barros
- Department of Physical Education, Dom Pedro II Military Firefighter Academy (ABMDPII), Rio de Janeiro, State of Rio de Janeiro, Brazil
- Department of Biosciences, Physical Education and Sports College of the Federal University of Rio de Janeiro (EEFD/UFRJ), State of Rio de Janeiro, Brazil
| | - Fabio Luiz Cândido Cahuê
- Department of Biosciences, Physical Education and Sports College of the Federal University of Rio de Janeiro (EEFD/UFRJ), State of Rio de Janeiro, Brazil
| | - Camilli Fernanda Martins Dos Santos
- Department of Biosciences, Physical Education and Sports College of the Federal University of Rio de Janeiro (EEFD/UFRJ), State of Rio de Janeiro, Brazil
| | - Bruna Karoline Lima Piazera
- Department of Biosciences, Physical Education and Sports College of the Federal University of Rio de Janeiro (EEFD/UFRJ), State of Rio de Janeiro, Brazil
| | - Verônica P Salerno
- Department of Biosciences, Physical Education and Sports College of the Federal University of Rio de Janeiro (EEFD/UFRJ), State of Rio de Janeiro, Brazil
| | - Mario Vaisman
- Department of Internal Medicine-Endocrinology, Federal University of Rio de Janeiro (FM-UFRJ), State of Rio de Janeiro, Brazil; and
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Magraner JMPDS, Talarico Neto T, Hahns Júnior HC, Tourinho Filho H, Martinelli Júnior CE. Serum Hormone Concentrations and Body Composition in Brazilian Air Force Cadets During Rainforest Survival Training. Mil Med 2023; 188:3302-3308. [PMID: 35803739 DOI: 10.1093/milmed/usac201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2022] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Physiological adaptations in military jungle survival training have not yet been studied. Knowledge about the relationship between the insulin-like growth factor type I (IGF-I)/insulin-like growth factor binding protein type 3 (IGFBP-3) system and survival activities in a jungle environment can improve readiness and prepare Brazilian Air Force cadets for this kind of battlefield. Our goal was to assess changes in body composition and serum concentrations of the IGF-I/IGFBP-3 system in Brazilian Air Force cadets during five-day Amazon rainforest survival training and whether differences in sex influence these variations. METHODS In the five-day survival training, variations in body composition and serum levels of IGF-I and IGFBP-3 were observed. The sample consisted of 14 male cadets (21.71 ± 1.64 years) and 6 female cadets (22.00 ± 1.41 years). Changes were assessed before and immediately after the survival training. RESULTS The male cadets' body mass (pre: 73.89 ± 8.79 kg; post: 69.57 ± 8.44 kg), body fat (pre: 11.43 ± 4.15%; post: 10.16 ± 4.19%), IGF-I serum concentrations (pre: 252 ± 72 ng/mL; post: 140 ± 42 ng/mL), and IGFBP-3 serum concentrations (pre: 4.90 ± 0.67 ng/mL; post: 4.22 ± 0.73 ng/mL) were significantly reduced (P < .01). In the female cadets, the mean body mass values (pre: 60.98 ± 8.82 kg; post: 57.91 ± 9.01 kg), body fat (pre: 19.20 ± 5.03%; post: 17.19 ± 4.77%), and IGF-I serum concentrations (pre: 202 ± 50 ng/mL; post: 108 ± 29 ng/mL) also decreased significantly (P < .01) after survival training. Finally, the cadet's sex does not affect the variations of IGF-I (P = .46) and IGFBP-3 (P = .205) serum concentrations. CONCLUSIONS These findings all suggest that changes in body mass and body fat, as well as variations in the IGF-I/IGFBP-3 system, corroborate the need for military readiness preparation. Equivalent changes in both sexes indicate probable equal recovery intervals after survival training.
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Affiliation(s)
- José Maurício Paixão Dos Santos Magraner
- Physical Education Faculty, State University of Campinas-UNICAMP, Cidade Universitária Zeferino Vaz-Barão Geraldo, Campinas-SP 13083-970, Brazil
- State University of Campinas-FEF/UNICAMP, Cidade Universitária Zeferino Vaz-Barão Geraldo, Campinas-SP 13083-970, Brazil
| | - Thomaz Talarico Neto
- School of Physical Education and Sport of Ribeirao Preto-EEFERP/USP, University of Sao Paulo-USP, Ribeirão Preto-SP 14049-900, Brazil
| | - Higino Carlos Hahns Júnior
- School of Physical Education and Sport of Ribeirao Preto-EEFERP/USP, University of Sao Paulo-USP, Ribeirão Preto-SP 14049-900, Brazil
| | - Hugo Tourinho Filho
- School of Physical Education and Sport of Ribeirao Preto-EEFERP/USP, University of Sao Paulo-USP, Ribeirão Preto-SP 14049-900, Brazil
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Sekel NM, Beckner ME, Conkright WR, LaGoy AD, Proessl F, Lovalekar M, Martin BJ, Jabloner LR, Beck AL, Eagle SR, Dretsch M, Roma PG, Ferrarelli F, Germain A, Flanagan SD, Connaboy C, Haufler AJ, Nindl BC. Military tactical adaptive decision making during simulated military operational stress is influenced by personality, resilience, aerobic fitness, and neurocognitive function. Front Psychol 2023; 14:1102425. [PMID: 36844343 PMCID: PMC9944034 DOI: 10.3389/fpsyg.2023.1102425] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 01/09/2023] [Indexed: 02/11/2023] Open
Abstract
Laboratory-based studies designed to mimic combat or military field training have consistently demonstrated deleterious effects on warfighter's physical, cognitive, and emotional performance during simulated military operational stress (SMOS). Purpose The present investigation sought to determine the impact of a 48-h simulated military operational stress (SMOS) on military tactical adaptive decision making, and the influence of select psychological, physical performance, cognitive, and physiological outcome measures on decision making performance. Methods Male (n = 48, 26.2 ± 5.5 years, 177.7 ± 6.6 cm, 84.7 ± 14.1 kg.) subjects currently serving in the U.S. military were eligible to participate in this study. Eligible subjects completed a 96-h protocol that occurred over five consecutive days and four nights. Day 2 (D2) and day 3 (D3) consisted of 48-h of SMOS wherein sleep opportunity and caloric needs were reduced to 50%. Differences in SPEAR total block score from baseline to peak stress (D3 minus D1) were calculated to assess change in military tactical adaptive decision making and groups were stratified based on increase (high adaptors) or decrease (low adaptors) of the SPEAR change score. Results Overall, military tactical decision-making declined 1.7% from D1 to D3 (p < 0.001). High adaptors reported significantly higher scores of aerobic capacity (p < 0.001), self-report resilience (p = 0.020), extroversion (p < 0.001), and conscientiousness (p < 0.001). at baseline compared to low adaptors, while low adaptors reported greater scores in Neuroticism (p < 0.001). Conclusion The present findings suggest that service members whose adaptive decision making abilities improved throughout SMOS (i.e., high adaptors) demonstrated better baseline psychological/self-reported resilience and aerobic capacity. Further, changes in adaptive decision-making were distinct from those of lower order cognitive functions throughout SMOS exposure. With the transition of future military conflicts placing higher priority on enhancing and sustaining cognitive readiness and resiliency, data presented here demonstrates the importance of measuring and categorizing baseline measures inherent to military personnel, in order to change and train one's ability to suffer less of a decline during high stress conditions.
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Affiliation(s)
- Nicole M. Sekel
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States,*Correspondence: Nicole M. Sekel, ✉
| | - Meaghan E. Beckner
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - William R. Conkright
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Alice D. LaGoy
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States,Military Sleep Tactics and Resilience Research Team, Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Felix Proessl
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Mita Lovalekar
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Brian J. Martin
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Leslie R. Jabloner
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Alaska L. Beck
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Shawn R. Eagle
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Michael Dretsch
- U.S. Army Medical Research Directorate-West, Walter Reed Army Institute of Research, Joint Base Lewis-McChord, Washington, WA, United States
| | - Peter G. Roma
- Behavioral Health and Performance Laboratory, Biomedical Research and Environmental Sciences Division, Human Health and Performance Directorate, KBR/NASA Johnson Space Center, Houston, TX, United States,Warfighter Performance Department, Operational Readiness and Health Directorate, Leidos/Naval Health Research Center, San Diego, CA, United States
| | - Fabio Ferrarelli
- Military Sleep Tactics and Resilience Research Team, Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Anne Germain
- Military Sleep Tactics and Resilience Research Team, Department of Psychiatry, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Shawn D. Flanagan
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Christopher Connaboy
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Amy J. Haufler
- Johns Hopkins University Applied Physics Laboratory, Laurel, MD, United States
| | - Bradley C. Nindl
- Neuromuscular Research Laboratory, Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
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Ponce T, Mainenti MRM, Cardoso EL, Ramos de Barros T, Pinto Salerno V, Vaisman M. Military field training exercise with prolonged physical activity and sleep restriction causes hormonal imbalance in firefighter cadets. J Endocrinol Invest 2023; 46:381-391. [PMID: 36057045 DOI: 10.1007/s40618-022-01913-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 08/26/2022] [Indexed: 01/25/2023]
Abstract
PURPOSE To evaluate the impact of the "Search and rescue" field military training exercise (SR_FTX) on hormonal modulation and identify their possible correlation with physical and cognitive performance. METHODS An observational (before and after) study was carried out, with male firefighters cadets (n = 42; age = 23[22;27] years) undergoing a nine-day military exercise (SR_FTX). The Countermovement jump (physical performance), the Stroop test (cognitive alertness), and blood tests for testosterone, cortisol, GH, and IGF-1 were applied. Wilcoxon for paired samples and Spearman's correlation tests were used. RESULTS Testosterone (751.10 [559.10;882.8] vs. 108.40 [80.12;156.40] ng/dL) and IGF-1 (217.5 [180;239.30] vs. 105 [93;129] ng/mL) significantly decreased while GH (0.10 [0.06;0.18] vs. 1.10 [0.58;2.28] ng/mL) and cortisol (9.60 [8.20;11.55] vs. 15.55 [12.28;18.98] ug/dL) significantly increased. Physical performance (31.2 [30.04;35.4] vs. 21.49 [19,02;23,59] cm) and cognitive alertness were significantly worse after SR_FTX (Congruent task: 1,78 (0183) vs. 1,56 (0185) response/s and incongruous task: 1,23 (0191) vs. 1,02 (0207) response/s). The physical performance showed a strong correlation with testosterone (rho = 0.694) and regular correlations with both IGF-1 (rho = 0.598) and cortisol (rho = - 0.580). The Stroop test presented weak correlations with GH (rho = - 0.350) and cortisol (rho = - 0.361). CONCLUSION SR_FTX negatively impacted hormonal modulation, physical and cognitive performance. These findings could help commanders decide to replace the employed firefighters in a real mission more frequently. Also, if the real scenario allows, they could think about providing better work conditions, such as improving caloric intake and rest periods, to preserve the military performance and health.
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Affiliation(s)
- T Ponce
- Academia de Bombeiro Militar Dom Pedro II (Dom Pedro II Military Firefighter Academy-ABMDPII), Rio de Janeiro, RJ, 21660-001, Brazil.
- Escola de Educação Física E Desportos (Physical Education and Sports College of the Federal University of Rio de Janeiro-EEFD/UFRJ), Rio de Janeiro, RJ, 21941-599, Brazil.
- Faculdade de Medicina-Endocrinologia (Medicine Collegof the Federal University of Rio de Janeiro-FM-UFRJ), Rio de Janeiro, RJ, 21941-617, Brazil.
| | - M R M Mainenti
- Escola de Educação Física do Exército (Physical Education College of the Brazilian Army-EsEFEx), Rio de Janeiro, RJ, 22291-090, Brazil
| | - E L Cardoso
- Escola de Educação Física E Desportos (Physical Education and Sports College of the Federal University of Rio de Janeiro-EEFD/UFRJ), Rio de Janeiro, RJ, 21941-599, Brazil
- Faculdade de Medicina-Endocrinologia (Medicine Collegof the Federal University of Rio de Janeiro-FM-UFRJ), Rio de Janeiro, RJ, 21941-617, Brazil
| | - T Ramos de Barros
- Academia de Bombeiro Militar Dom Pedro II (Dom Pedro II Military Firefighter Academy-ABMDPII), Rio de Janeiro, RJ, 21660-001, Brazil
- Escola de Educação Física E Desportos (Physical Education and Sports College of the Federal University of Rio de Janeiro-EEFD/UFRJ), Rio de Janeiro, RJ, 21941-599, Brazil
| | - V Pinto Salerno
- Escola de Educação Física E Desportos (Physical Education and Sports College of the Federal University of Rio de Janeiro-EEFD/UFRJ), Rio de Janeiro, RJ, 21941-599, Brazil
| | - M Vaisman
- Faculdade de Medicina-Endocrinologia (Medicine Collegof the Federal University of Rio de Janeiro-FM-UFRJ), Rio de Janeiro, RJ, 21941-617, Brazil
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8
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Physiological biomarker monitoring during arduous military training: Maintaining readiness and performance. J Sci Med Sport 2022:S1440-2440(22)00502-3. [PMID: 36631385 DOI: 10.1016/j.jsams.2022.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Revised: 12/06/2022] [Accepted: 12/19/2022] [Indexed: 12/24/2022]
Abstract
OBJECTIVES Physiological and psychological stressors can degrade soldiers' readiness and performance during military training and operational environments. Integrative and holistic assessments of biomarkers across diverse human performance optimization domains during multistressor training can be leveraged to provide actionable insight to military leadership regarding service member health and readiness. DESIGN/METHOD A broad categorization of biomarkers, to include biochemical measures, bone and body composition, psychometric assessments, movement screening, and physiological load can be incorporated into robust analytical pipelines for understanding the complex factors that impact military human performance. RESULTS In this perspective commentary we overview the rationale, selection, and methodologies for monitoring biomarker domains that are relevant to military research and specifically highlight methods that have been incorporated in a research program funded by the Office of Naval Research, Code 34 Biological and Physiological Monitoring and Modeling of Warfighter Performance. CONCLUSIONS The integration of screening and continuous monitoring methodologies via robust analytical approaches will provide novel insight for military leaders regarding health, performance, and readiness outcomes during multistressor military training.
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9
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Ledford AK, Beckner ME, Conkright WR, Raver C, Dixon DP, Miles P, Martin B, Nindl BC, Lynch SM. Psychological and physiological changes during basic, underwater, demolition/SEAL training. Physiol Behav 2022; 257:113970. [PMID: 36179811 PMCID: PMC10284119 DOI: 10.1016/j.physbeh.2022.113970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 09/20/2022] [Accepted: 09/22/2022] [Indexed: 11/16/2022]
Abstract
This longitudinal study examines the growth of psychological characteristics and adaptation of physiological markers of stress during a six-month assessment and selection course for U.S. Navy SEALs. Resilience, hardiness, and grit instruments were used to evaluate the psychological characteristics. Blood samples were taken to determine physiological markers related to stress adaptation; specifically, evaluating DHEA, DHEA-to-cortisol ratio, BDNF, NPY, and cortisol. Data was collected at four timepoints throughout the assessment and selection course from 353 students over three classes. Results indicated that resilience and hardiness grow after an initial decline, DHEA and DHEA-to-cortisol increased suggesting physiological adaptation. However, psychological and physiological markers do not exhibit the same growth patterns for participants in the course. This study enhances the understanding of psychological growth and physiological adaptation in a high-stress environment over an extended duration.
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Affiliation(s)
- Andrew K Ledford
- Department of Leadership, Ethics, and Law, United States Naval Academy, United States.
| | | | - William R Conkright
- Deputy Chief, Nutrition Care Division, Madigan Army Medical Center, United States
| | - Celeste Raver
- Stockdale Center for Ethical Leadership, United States Naval Academy, United States
| | - Deirdre P Dixon
- TECO Energy Center for Leadership, Sykes College of Business, The University of Tampa, United States
| | - Patti Miles
- Maine Business School, University of Maine, United States
| | - Brian Martin
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, University of Pittsburgh, United States
| | - Bradley C Nindl
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, University of Pittsburgh, United States
| | - Scott M Lynch
- Center for Population Health and Aging, Department of Sociology, Duke University
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10
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Beckner ME, Conkright WR, Mi Q, Martin BJ, Sahu A, Flanagan SD, Ledford AK, Wright M, Susmarski A, Ambrosio F, Nindl BC. Neuroendocrine, Inflammatory, and Extracellular Vesicle Responses During the Navy Special Warfare Screener Selection Course. Physiol Genomics 2022; 54:283-295. [PMID: 35695270 PMCID: PMC9291410 DOI: 10.1152/physiolgenomics.00184.2021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Military operational stress is known to increase adrenal hormones and inflammatory cytokines, while decreasing hormones associated with the anabolic milieu and neuroendocrine system. Less is known about the role of extracellular vesicles (EVs), a form of cell-to-cell communication, in military operational stress and their relationship to circulating hormones. PURPOSE To characterize the neuroendocrine, cytokine, and EV response to an intense, 24-h selection course known as the Naval Special Warfare (NSW) Screener and identify associations between EVs and cytokines. METHODS Blood samples were collected the morning of and following the NSW Screener in 29 men (18 - 26 years). Samples were analyzed for concentrations of cortisol, insulin-like growth factor I (IGF-I), neuropeptide-Y (NPY), brain-derived neurotrophic factor (BDNF), α-klotho, tumor necrosis factor- α (TNFα), and interleukins (IL) -1β, -6, and -10. EVs stained with markers associated with exosomes (CD63), microvesicles (VAMP3), and apoptotic bodies (THSD1) were characterized using imaging flow cytometry and vesicle flow cytometry. RESULTS The selection event induced significant changes in circulating BDNF (-43.2%), IGF-I (-24.56%), TNFα (+17.7%), IL-6 (+13.6%), accompanied by increases in intensities of THSD1+ and VAMP3+ EVs (all p<0.05). Higher concentrations of IL-1β and IL-10 were positively associated with THSD1+ EVs (p<0.05). CONCLUSION Military operational stress altered the EV profile. Surface markers associated with apoptotic bodies were positively correlated with an inflammatory response. Future studies should consider a multi-omics assessment of EV cargo to discern canonical pathways that may be mediated by EVs during military stress.
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Affiliation(s)
- Meaghan E Beckner
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, PA, United States
| | - William R Conkright
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, PA, United States
| | - Qi Mi
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, PA, United States
| | - Brian J Martin
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, PA, United States
| | - Amrita Sahu
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States
| | - Shawn D Flanagan
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, PA, United States
| | - Andrew K Ledford
- Department of Leadership, Ethics, and Law, U.S. Naval Academy, Annapolis, MD, United States
| | - Martin Wright
- Human Performance Lab, Physical Education Department, U.S. Naval Academy, Annapolis, MD, United States
| | - Adam Susmarski
- Brigade Orthopedics and Sports Medicine, U.S. Navy Academy, Annapolis, MD, United States
| | - Fabrisia Ambrosio
- Department of Physical Medicine and Rehabilitation, University of Pittsburgh, Pittsburgh, PA, United States.,McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, United States
| | - Bradley C Nindl
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, PA, United States
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11
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E Silva FB, Vaisman M, Ponce T, de Barros TR, E Silva CB, Salerno VP, Mainenti MRM. A systematic review of hormone levels, biomarkers of cellular injury and oxidative stress in multi-stressor military field training exercises. ARCHIVES OF ENDOCRINOLOGY AND METABOLISM 2022; 66:2359-3997000000443. [PMID: 35289515 PMCID: PMC9832854 DOI: 10.20945/2359-3997000000443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Accepted: 11/05/2021] [Indexed: 11/23/2022]
Abstract
The fundamental objective of military field training exercises (FTX) is to prepare military personnel for real-life operations through simulated scenarios. These training sessions often require extreme physical efforts with prolonged, high-intensity exercises that can be combined with food restrictions and partial, or total, sleep deprivation. Such conditions can compromise an individual's physical performance and cause tissue damage, thus affecting their health. This study aimed to perform a systematic review of the literature to identify studies that measured the changes in hormone levels and biomarkers of cellular injury and oxidative stress resulting from FTX with high levels of energy expenditure combined with food and sleep restrictions. PubMed and the Scopus database were searched for articles that combined physical effort/food restriction/sleep deprivation with military training. The initial database search identified 158 articles that were reduced to 18 after confirmation. Significant reductions were reported in thyroid hormones, T3, T4, and anabolic hormones such as testosterone, insulin and androstenedione. An exception for GH was found, which increased throughout FTX. Less distinct responses to FTX were observed with cortisol, TSH and LH. The presence of biomarkers for cellular damage (myoglobin, TNF, and CRP) and increased immune response activities were also described. The scarcity of information on oxidative stress, analyses of cellular injury and biomarkers of inflammatory responses warrants the future study of these topics, which could be helpful in facilitating the safe and effective physical preparations of the members of the armed forces.
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Affiliation(s)
| | - Mario Vaisman
- Departamento de Medicina Interna - Endocrinologia, Faculdade de Medicina, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - Thalita Ponce
- Departamento de Medicina Interna - Endocrinologia, Faculdade de Medicina, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
- Escola de Educação Física e Desportos, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - Thiago Ramos de Barros
- Escola de Educação Física e Desportos, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
- Academia de Bombeiro Militar Dom Pedro II, Rio de Janeiro, RJ, Brasil
| | - Camila Brasil E Silva
- Companhia de Comando da 4ª Brigada de Infantaria Leve de Montanha - Exército Brasileiro, Juiz de Fora, MG, Brasil
| | - Verônica Pinto Salerno
- Escola de Educação Física e Desportos, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
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12
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O'Leary TJ, Walsh NP, Casey A, Izard RM, Tang JCY, Fraser WD, Greeves JP. Supplementary Energy Increases Bone Formation during Arduous Military Training. Med Sci Sports Exerc 2021; 53:394-403. [PMID: 32701874 DOI: 10.1249/mss.0000000000002473] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
PURPOSE This study aimed to investigate the effect of supplementary energy on bone formation and resorption during arduous military training in energy deficit. METHODS Thirty male soldiers completed an 8-wk military combat course (mean ± SD, age = 25 ± 3 yr, height = 1.78 ± 0.05 m, body mass = 80.9 ± 7.7 kg). Participants received either the habitual diet (control group, n = 15) or an additional 5.1 MJ·d-1 to eliminate the energy deficit (supplemented group, n = 15). Circulating markers of bone formation and resorption, and reproductive, thyroid, and metabolic status, were measured at baseline and weeks 6 and 8 of training. RESULTS Bone-specific alkaline phosphatase decreased in controls (-4.4 ± 1.9 μg·L-1) and increased in the supplemented group (16.0 ± 6.6 μg·L-1), between baseline and week 8 (P < 0.001). Procollagen type 1 N-terminal propeptide increased between baseline and week 6 for both groups (5.6 ± 8.1 μg·L-1, P = 0.005). Beta carboxy-terminal cross-linking telopeptide of type 1 collagen decreased between baseline and week 8 for both groups (-0.16 ± 0.20 μg·L-1, P < 0.001). Prolactin increased from baseline to week 8 for the supplemented group (148 ± 151 IU·L-1, P = 0.041). The increase in adiponectin from baseline to week 8 was higher in controls (4.3 ± 1.8 mg·L-1, P < 0.001) than that in the supplemented group (1.4 ± 1.0 mg·L-1, P < 0.001). Insulin-like growth factor binding protein-3 was lower at week 8 than baseline for controls (-461 ± 395 ng·mL-1, P < 0.001). CONCLUSION The increase in bone-specific alkaline phosphatase, a marker of bone formation, with supplementation supports a role of energy in osteoblastic activity; the implications for skeletal adaptation and stress fracture risk are unclear. The mechanism is likely through protecting markers of metabolic, but not reproductive or thyroid, function.
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Affiliation(s)
- Thomas J O'Leary
- Army Health and Performance Research, Army Headquarters, Andover, UNITED KINGDOM
| | - Neil P Walsh
- Research Institute for Sport and Exercise Science, Liverpool John Moores University, Liverpool, UNITED KINGDOM
| | - Anna Casey
- Army Health and Performance Research, Army Headquarters, Andover, UNITED KINGDOM
| | - Rachel M Izard
- Department of Occupational Medicine, HQ Army Recruiting and Initial Training Command, Upavon, UNITED KINGDOM
| | - Jonathan C Y Tang
- Norwich Medical School, University of East Anglia, Norwich, UNITED KINGDOM
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13
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O'Leary TJ, Wardle SL, Greeves JP. Energy Deficiency in Soldiers: The Risk of the Athlete Triad and Relative Energy Deficiency in Sport Syndromes in the Military. Front Nutr 2020; 7:142. [PMID: 32984399 PMCID: PMC7477333 DOI: 10.3389/fnut.2020.00142] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 07/21/2020] [Indexed: 12/15/2022] Open
Abstract
Military personnel experience energy deficit (total energy expenditure higher than energy intake), particularly during combat training and field exercises where exercising energy expenditures are high and energy intake is reduced. Low energy availability (energy intake minus exercising energy expenditure expressed relative to fat free mass) impairs endocrine function and bone health, as recognized in female athletes as the Female Athlete Triad syndrome. More recently, the Relative Energy Deficiency in Sport (RED-S) syndrome encompasses broader health outcomes, physical and cognitive performance, non-athletes, and men. This review summarizes the evidence for the effect of low energy availability and energy deficiency in military training and operations on health and performance outcomes. Energy availability is difficult to measure in free-living individuals but doubly labeled water studies demonstrate high total energy expenditures during military training; studies that have concurrently measured energy intake, or measured body composition changes with DXA, suggest severe and/or prolonged energy deficits. Military training in energy deficit disturbs endocrine and metabolic function, menstrual function, bone health, immune function, gastrointestinal health, iron status, mood, and physical and cognitive performance. There are more data for men than women, and little evidence on the chronic effects of repeated exposures to energy deficit. Military training impairs indices of health and performance, indicative of the Triad and RED-S, but the multi-stressor environment makes it difficult to isolate the independent effects of energy deficiency. Studies supplementing with energy to attenuate the energy deficit suggest an independent effect of energy deficiency in the disturbances to metabolic, endocrine and immune function, and physical performance, but randomized controlled trials are lacking.
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Affiliation(s)
- Thomas J O'Leary
- Army Health and Performance Research, Army Headquarters, Andover, United Kingdom.,Division of Surgery and Interventional Science, UCL, London, United Kingdom
| | - Sophie L Wardle
- Army Health and Performance Research, Army Headquarters, Andover, United Kingdom.,Division of Surgery and Interventional Science, UCL, London, United Kingdom
| | - Julie P Greeves
- Army Health and Performance Research, Army Headquarters, Andover, United Kingdom.,Division of Surgery and Interventional Science, UCL, London, United Kingdom.,Norwich Medical School, University of East Anglia, Norwich, United Kingdom
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14
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Jensen AE, Bernards JR, Jameson JT, Johnson DC, Kelly KR. The Benefit of Mental Skills Training on Performance and Stress Response in Military Personnel. Front Psychol 2020; 10:2964. [PMID: 31993011 PMCID: PMC6970970 DOI: 10.3389/fpsyg.2019.02964] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 12/16/2019] [Indexed: 01/13/2023] Open
Abstract
Mental skills training (MST) has been suggested to reduce stress in civilian and athletic populations, however, whether these techniques and practices transfer to a military population are unknown. Therefore, the purpose of this study was to evaluate two MST programs against a baseline condition, training-as-usual (TAU), during an intense, active-duty, military training environment. Two hundred and three Marines enrolled in the United States Marine Corps' Basic Reconnaissance Course participated in this effort (n = 203; age = 22.7 ± 3.3 years; height = 178 ± 6.35 cm; weight = 97.7 ± 8.3 kg; Mean ± SD). Each Marine was assigned to one of three groups, Mindfulness-Based Mind Fitness Training (MMFT), General Mental Skills Training (GMST), or TAU. Operational and cognitive performance measures, as well as, physiological metrics were obtained across three training phases (phase 1-3). Furthermore, phase 3 was sub-divided into pre-ambush, ambush and post-ambush time points. Significant group × time interactions were found for the total number of errors committed on the sustained attention response task (p = 0.004); as well as, plasma cortisol (p < 0.0001) and insulin-like growth factor-1 (IGF-1; p < 0.0001). There were mixed results between groups on operational performance tasks with the MST groups tending to perform better than TAU the more time participants had with MST instruction. During ambush, the differences among groups were especially pronounced for measures of information processing that one would expect MST to enhance: coordinates recall, plot time, and plot accuracy (p < 0.001), with improvements ranging from 24.7 to 87.9% for the MST conditions when compared to TAU. These data demonstrate that independent of the specific type of MST program, the fundamental characteristics of stress regulation embedded within each MST program may enhance performance and cognitive function during time of heightened stress.
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Affiliation(s)
| | | | | | | | - Karen R. Kelly
- Naval Health Research Center, San Diego, CA, United States
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15
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Nindl BC, Ahtiainen J, Gagnon SS, Taipale RS, Pierce JR, Martin BJ, Beckner ME, Lehti M, Häkkinen K, Kyröläinen H. Microdialysis-Assessed Exercised Muscle Reveals Localized and Differential IGFBP Responses to Unilateral Stretch Shortening Cycle Exercise. Front Endocrinol (Lausanne) 2020; 11:315. [PMID: 32547489 PMCID: PMC7272679 DOI: 10.3389/fendo.2020.00315] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Accepted: 04/24/2020] [Indexed: 01/10/2023] Open
Abstract
Microdialysis allows for a preview into local muscle metabolism and can provide physiological insight that blood measurements cannot. Purpose: To examine the potential differential IGF-I system regulation in interstitial fluid during unilateral stretch shortening cycle exercise. Methods: 10 men (26 ± 7 year) performed unilateral jumping [stretch shortening cycle (SSC) exercise at 50% of optimal jump height] until volitional fatigue on a sled apparatus. Biological sampling took place using a catheter inserted into an antecubital vein (serum), and 100 kDa microdialysis probes inserted into the thigh muscle of each exercise/control leg (dialysate). Serum was drawn before (Pre; -3 h) and after SSC [Post I (+0 h), II (+3 h), or III (+20 h)]; dialysate was sampled for 2 h before (Pre), during/immediately after (Ex), and 3 h into recovery (Rec) following SSC. IGF-I system parameters (free/total IGF-I and IGFBPs 1-6) were measured with immunoassays. Interstitial free IGF-I was estimated from dialysate IGF-I and relative recovery (ethanol) correction. Data were analyzed with repeated measures ANOVA. Results: Serum total IGF-I remained elevated +3 h (Post II: 182.8 ± 37.6 vs. Pre: 168.3 ± 35.0 ng/mL, p < 0.01), but returned to baseline by +20 h (Post III vs. Pre, p = 0.31). No changes in serum free IGF-I were noted. Serum BP-1 and -3 increased over baseline, but not until + 20 h after SSC (Post III vs. Pre: 7.6 ± 4.9 vs. 3.7 ± 2.3 and 1,048.6 ± 269.2 vs. 891.4 ± 171.2 ng/mL, respectively). We observed a decreased serum BP-6 +3 h after SSC (p < 0.01), followed by a return to baseline at +20 h (p = 0.64 vs. Pre). There were no exercise-induced changes in serum BP-2, -4, or -5. Unlike serum, there were no changes in dialysate or interstitial free IGF-I in either leg (p > 0.05). Dialysate BP-1 remained increased in both exercise and control legs through 3 h into recovery (Rec vs. Pre, p < 0.01). Dialysate BP-3 also demonstrated a prolonged elevation over Pre SSC concentrations, but in the exercise leg only (Ex and Rec vs. Pre, p < 0.04). We observed a prolonged decrease in dialysate BP-5 (Ex and Rec vs. Pre, p < 0.03) and an increase in BP-4 IP in the exercise leg only. There were no changes relative to Pre SSC in dialysate BP-2 or -6. Conclusions: Unilateral exercise drives differential regulation of the IGF-I system at both local and systemic levels. More specifically, this is the first study to demonstrate that localized exercise increases IGFBP-3, IGFBP-4 and decreases in IGFBP-5 in muscle interstitial fluid.
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Affiliation(s)
- Bradley C. Nindl
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
- US Army Research Institute of Environmental Medicine, Natick, MA, United States
- Army Public Health Center, Aberdeen Proving Ground, MD, United States
- *Correspondence: Bradley C. Nindl
| | - Juha Ahtiainen
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyvaskyla, Finland
| | - Sheila S. Gagnon
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyvaskyla, Finland
| | - Ritva S. Taipale
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyvaskyla, Finland
| | - Joseph R. Pierce
- US Army Research Institute of Environmental Medicine, Natick, MA, United States
- Army Public Health Center, Aberdeen Proving Ground, MD, United States
| | - Brian J. Martin
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - Meaghan E. Beckner
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, United States
| | - M. Lehti
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyvaskyla, Finland
| | - Keijo Häkkinen
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyvaskyla, Finland
| | - Heikki Kyröläinen
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Jyvaskyla, Finland
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16
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HAMARSLAND HÅVARD, PAULSEN GØRAN, SOLBERG PAULA, SLAATHAUG OLEGUNNAR, RAASTAD TRULS. Depressed Physical Performance Outlasts Hormonal Disturbances after Military Training. Med Sci Sports Exerc 2018; 50:2076-2084. [DOI: 10.1249/mss.0000000000001681] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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17
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Ojanen T, Jalanko P, Kyröläinen H. Physical fitness, hormonal, and immunological responses during prolonged military field training. Physiol Rep 2018; 6:e13850. [PMID: 30187684 PMCID: PMC6125608 DOI: 10.14814/phy2.13850] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Revised: 08/06/2018] [Accepted: 08/10/2018] [Indexed: 11/24/2022] Open
Abstract
Physical fitness is crucial to warfighters' performance in the battlefield. Previous studies have shown negative changes in their hormonal and neuromuscular responses induced by military field training (MFT). The purpose of this study was to investigate the changes in hormonal and immunological values and body composition during a prolonged MFT and to find out how warfighters' physical condition influences these changes. Conscripts (n = 49, age 20 ± 1 years, height 179 ± 9 cm, body mass 73.8 ± 7.8 kg, fat 12.6 ± 3.7% and BMI 23 kg/m²) were measured before, during, after MFT, and after a 4-day recovery period. Serum insulin-like growth factor-1 (IGF-1), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6) concentrations, creatine kinase (CK) activity and leptin concentration were analyzed as well as body composition throughout MFT. Neuromuscular performance was assessed via lower and upper body muscle endurance at the beginning of the study. During MFT, there was a significant decrease (P < 0.05) in body mass (2.3%), fat mass (7.7%) and in muscle mass (2.2%), but all of these values recovered to PRE-levels after the recovery period. Serum IGF-1 (22%) and leptin decreased (66%) while CK increased (88%) significantly (P < 0.05) during MFT but recovered at the end of MFT. Upper body dynamic and trunk isometric muscular endurance had a positive correlation (r = 0.37. P < 0.05) with the change in IGF-1 during MFT and a negative correlation with the changes in CK (-0.34, P < 0.05). The results show that there were negative changes in conscript's body composition and hormonal and immunological values during the prolonged MFT. These changes suggest that the physiological stress was high during MFT. High levels of upper body and trunk muscular strength were negatively correlated with warfighters' physiological effects and should therefore be developed prior to actual deployment to reduce the physical decline experienced during prolonged MFTs.
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Affiliation(s)
- Tommi Ojanen
- Finnish Defence Research AgencyFinnish Defence ForcesJärvenpääFinland
| | - Petri Jalanko
- Biology of Physical ActivityUniversity of JyväskyläJyväskyläFinland
| | - Heikki Kyröläinen
- Biology of Physical ActivityUniversity of JyväskyläJyväskyläFinland
- National Defence UniversityHelsinkiFinland
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18
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Ojanen T, Kyröläinen H, Igendia M, Häkkinen K. Effect of Prolonged Military Field Training on Neuromuscular and Hormonal Responses and Shooting Performance in Warfighters. Mil Med 2018; 183:e705-e712. [DOI: 10.1093/milmed/usy122] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Indexed: 11/13/2022] Open
Affiliation(s)
- Tommi Ojanen
- Finnish Defence Research Agency, Finnish Defence Forces, Järvenpää, Finland
| | - Heikki Kyröläinen
- Biology of Physical Activity, Faculty of Sport and Health Sciences, University of Jyväskylä., Jyväskylä, Finland
- National Defence University, Helsinki, Finland
| | - Mikael Igendia
- Biology of Physical Activity, Faculty of Sport and Health Sciences, University of Jyväskylä., Jyväskylä, Finland
| | - Keijo Häkkinen
- Biology of Physical Activity, Faculty of Sport and Health Sciences, University of Jyväskylä., Jyväskylä, Finland
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19
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Karl JP, Margolis LM, Murphy NE, Carrigan CT, Castellani JW, Madslien EH, Teien HK, Martini S, Montain SJ, Pasiakos SM. Military training elicits marked increases in plasma metabolomic signatures of energy metabolism, lipolysis, fatty acid oxidation, and ketogenesis. Physiol Rep 2017; 5:e13407. [PMID: 28899914 PMCID: PMC5599865 DOI: 10.14814/phy2.13407] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 08/06/2017] [Accepted: 08/10/2017] [Indexed: 01/08/2023] Open
Abstract
Military training studies provide unique insight into metabolic responses to extreme physiologic stress induced by multiple stressor environments, and the impacts of nutrition in mediating these responses. Advances in metabolomics have provided new approaches for extending current understanding of factors modulating dynamic metabolic responses in these environments. In this study, whole-body metabolic responses to strenuous military training were explored in relation to energy balance and macronutrient intake by performing nontargeted global metabolite profiling on plasma collected from 25 male soldiers before and after completing a 4-day, 51-km cross-country ski march that produced high total daily energy expenditures (25.4 MJ/day [SD 2.3]) and severe energy deficits (13.6 MJ/day [SD 2.5]). Of 737 identified metabolites, 478 changed during the training. Increases in 88% of the free fatty acids and 91% of the acylcarnitines, and decreases in 88% of the mono- and diacylglycerols detected within lipid metabolism pathways were observed. Smaller increases in 75% of the tricarboxylic acid cycle intermediates, and 50% of the branched-chain amino acid metabolites detected were also observed. Changes in multiple metabolites related to lipid metabolism were correlated with body mass loss and energy balance, but not with energy and macronutrient intakes or energy expenditure. These findings are consistent with an increase in energy metabolism, lipolysis, fatty acid oxidation, ketogenesis, and branched-chain amino acid catabolism during strenuous military training. The magnitude of the energy deficit induced by undereating relative to high energy expenditure, rather than macronutrient intake, appeared to drive these changes, particularly within lipid metabolism pathways.
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Affiliation(s)
- J Philip Karl
- Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - Lee M Margolis
- Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
- Oak Ridge Institute for Science and Education, Oak Ridge, Tennessee
| | - Nancy E Murphy
- Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - Christopher T Carrigan
- Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - John W Castellani
- Thermal and Mountain Medicine Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | | | | | - Svein Martini
- Norwegian Defense Research Establishment, Kjeller, Norway
| | - Scott J Montain
- Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - Stefan M Pasiakos
- Military Nutrition Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
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Karl JP, Smith TJ, Wilson MA, Bukhari AS, Pasiakos SM, McClung HL, McClung JP, Lieberman HR. Altered metabolic homeostasis is associated with appetite regulation during and following 48-h of severe energy deprivation in adults. Metabolism 2016; 65:416-27. [PMID: 26975533 DOI: 10.1016/j.metabol.2015.11.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2015] [Revised: 09/29/2015] [Accepted: 11/04/2015] [Indexed: 12/19/2022]
Abstract
BACKGROUND Military personnel frequently endure intermittent periods of severe energy deficit which can compromise health and performance. Physiologic factors contributing to underconsumption, and the subsequent drive to overeat, are not fully characterized. This study aimed to identify associations between appetite, metabolic homeostasis and endocrine responses during and following severe, short-term energy deprivation. METHODS Twenty-three young adults (17M/6F, 21±3years, BMI 25±3kg/m(2)) participated in a randomized, controlled, crossover trial. During separate 48-h periods, participants increased habitual energy expenditure by 1647±345kcal/d (mean±SD) through prescribed exercise at 40-65% VO2peak, and consumed provided isovolumetric diets designed to maintain energy balance at the elevated energy expenditure (EB; 36±93kcal/d energy deficit) or to produce a severe energy deficit (ED; 3681±716kcal/d energy deficit). Appetite, markers of metabolic homeostasis and endocrine mediators of appetite and substrate availability were periodically measured. Ad libitum energy intake was measured over 36h following both experimental periods. RESULTS Appetite increased during ED and was greater than during EB despite maintenance of diet volume (P=0.004). Ad libitum energy intake was 907kcal/36h [95% CI: 321, 1493kcal/36h, P=0.004] higher following ED compared to following EB. Serum beta-hydroxybutyrate, free fatty acids, branched-chain amino acids, dehydroepiandrosterone-sulfate (DHEA-S) and cortisol concentrations were higher (P<0.001 for all), whereas whole-body protein balance was more negative (P<0.001), and serum glucose, insulin, and leptin concentrations were lower (P<0.001 for all) during ED relative to during EB. Cortisol concentrations, but not any other hormone or metabolic substrate, were inversely associated with satiety during EB (R(2)=0.23, P=0.04). In contrast, serum glucose and DHEA-S concentrations were inversely associated with satiety during ED (R(2)=0.68, P<0.001). No associations between physiologic variables measured during EB and ad libitum energy intake following EB were observed. However, serum leptin and net protein balance measured during ED were inversely associated with ad libitum energy intake following ED (R(2)=0.48, P=0.01). CONCLUSION These findings suggest that changes in metabolic homeostasis during energy deprivation modulate appetite independent of reductions in diet volume. Following energy deprivation, physiologic signals of adipose and lean tissue loss may drive restoration of energy balance. CLINICAL TRIALS REGISTRATION www.clinicaltrials.gov #NCT01603550.
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Affiliation(s)
- J Philip Karl
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, 10 General Greene Ave, Bldg 42, Natick, MA 01760, USA.
| | - Tracey J Smith
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, 10 General Greene Ave, Bldg 42, Natick, MA 01760, USA
| | - Marques A Wilson
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, 10 General Greene Ave, Bldg 42, Natick, MA 01760, USA
| | - Asma S Bukhari
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, 10 General Greene Ave, Bldg 42, Natick, MA 01760, USA
| | - Stefan M Pasiakos
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, 10 General Greene Ave, Bldg 42, Natick, MA 01760, USA
| | - Holly L McClung
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, 10 General Greene Ave, Bldg 42, Natick, MA 01760, USA
| | - James P McClung
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, 10 General Greene Ave, Bldg 42, Natick, MA 01760, USA
| | - Harris R Lieberman
- Military Nutrition Division, US Army Research Institute of Environmental Medicine, 10 General Greene Ave, Bldg 42, Natick, MA 01760, USA
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21
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Ritsche K, Nindl BC, Wideman L. Exercise-Induced growth hormone during acute sleep deprivation. Physiol Rep 2014; 2:2/10/e12166. [PMID: 25281616 PMCID: PMC4254093 DOI: 10.14814/phy2.12166] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The effect of acute (24‐h) sleep deprivation on exercise‐induced growth hormone (GH) and insulin‐like growth factor‐1 (IGF‐1) was examined. Ten men (20.6 ± 1.4 years) completed two randomized 24‐h sessions including a brief, high‐intensity exercise bout following either a night of sleep (SLEEP) or (24‐h) sleep deprivation (SLD). Anaerobic performance (mean power [MP], peak power [PP], minimum power [MinP], time to peak power [TTPP], fatigue index, [FI]) and total work per sprint [TWPS]) was determined from four maximal 30‐sec Wingate sprints on a cycle ergometer. Self‐reported sleep 7 days prior to each session was similar between SLEEP and SLD sessions (7.92 ± 0.33 vs. 7.98 ± 0.39 h, P =0.656, respectively) and during the actual SLEEP session in the lab, the total amount of sleep was similar to the 7 days leading up to the lab session (7.72 ± 0.14 h vs. 7.92 ± 0.33 h, respectively) (P =0.166). No differences existed in MP, PP, MinP, TTPP, FI, TWPS, resting GH concentrations, time to reach exercise‐induced peak GH concentration (TTP), or free IGF‐1 between sessions. GH area under the curve (AUC) (825.0 ± 199.8 vs. 2212.9 ± 441.9 μg/L*min, P <0.01), exercise‐induced peak GH concentration (17.8 ± 3.7 vs. 39.6 ± 7.1 μg/L, P <0.01) and ΔGH (peak GH – resting GH) (17.2 ± 3.7 vs. 38.2 ± 7.3 μg/L, P <0.01) were significantly lower during the SLEEP versus SLD session. Our results indicate that the exercise‐induced GH response was significantly augmented in sleep‐deprived individuals. Human growth hormone release is heavily influenced by sleep and exercise. Our study shows that sleep deprivation dramatically augments the exercise‐induced human growth hormone response.
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Affiliation(s)
- Kevin Ritsche
- Department of Kinesiology, University of North Carolina-Greensboro, Greensboro, North Carolina, USA Department of Exercise Physiology, Winston-Salem State University, Winston-Salem, North Carolina, USA
| | - Bradly C Nindl
- US Army Institute of Public Health, US Army Public Health Command, Aberdeen, Proving Ground, Aberdeen, Maryland, USA
| | - Laurie Wideman
- Department of Kinesiology, University of North Carolina-Greensboro, Greensboro, North Carolina, USA
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Henning PC, Scofield DE, Spiering BA, Staab JS, Matheny RW, Smith MA, Bhasin S, Nindl BC. Recovery of endocrine and inflammatory mediators following an extended energy deficit. J Clin Endocrinol Metab 2014; 99:956-64. [PMID: 24423293 DOI: 10.1210/jc.2013-3046] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Due to current operational requirements, elite soldiers deploy quickly after completing arduous training courses. Therefore, it is imperative that endocrine and inflammatory mediators have fully recovered. OBJECTIVE Our objective was to determine whether a short-term (2-6 wk) recovery period was sufficient to restore endocrine and inflammatory homeostasis after sustained energy deficit. DESIGN Before and immediately after the course, serum concentrations of inflammatory and endocrine markers were taken along with anthropometric measures prior to and immediately after the Army Ranger course. In addition, nine soldiers were assessed between 2 and 6 weeks after the course. SETTING This research occurred in a field setting during an intensive 8-week military training course characterized by high-energy expenditure, energy restriction, and sleep deprivation (U.S. Army Ranger School). PARTICIPANTS Twenty-three male soldiers (23.0 ± 2.8 y; 177.6 ± 7.9 cm; 81.0 ± 9.6 kg, 16.8 ± 3.9% body fat) participated in this study. INTERVENTIONS There were no interventions used in this research. OUTCOME MEASURES AND RESULTS Significant changes occurred in circulating total testosterone (-70%), brain-derived neurotrophic factor (-33%), total IGF-1 (-38.7%), free IGF-1 (-41%), IGF binding protein (IGFBP-6; -23.4%), sex-hormone binding globulin (+46%), thyroid stimulating hormone (+85%), IGFBP-1 (+534.4%), IGFBP-2 (+98.3%), IGFBP-3 (+14.7%), IL-4 (+135%), IL-6 (+217%), and IL-8 (+101%). Significant changes in body mass (-8%), bicep (-14%), forearm (-5%), thigh (-7%), and calf (-2%) circumferences, sum of skinfolds (-52%), and percentage body fat (-54%). All anthropometric, inflammatory, and hormonal values, except T3, were restored to baseline levels within 2-6 weeks after the course. CONCLUSIONS Endocrine markers and anthropometric measures were degraded, and inflammatory mediators increased after an extended energy deficit. A short-term recovery of 2-6 weeks was sufficient to restore these mediators.
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Affiliation(s)
- Paul C Henning
- Military Performance Division (P.C.H., D.E.S., B.A.S., J.S.S., R.W.M., B.C.N.), U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts 01760; Madigan Healthcare System (M.A.S.), Joint Base Lewis-McChord, Washington 98431; and Sections of Endocrinology (S.B.), Diabetes, and Nutrition, Boston University School of Medicine, Boston University, Boston, Massachusetts 02118; and Army Institute of Public Health Army Public Health Command (B.C.N.), Aberdeen Proving Ground, Maryland 21010
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Henning PC, Scofield DE, Rarick KR, Pierce JR, Staab JS, Lieberman HR, Nindl BC. Effects of acute caloric restriction compared to caloric balance on the temporal response of the IGF-I system. Metabolism 2013; 62:179-87. [PMID: 22906764 DOI: 10.1016/j.metabol.2012.07.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2012] [Revised: 07/11/2012] [Accepted: 07/11/2012] [Indexed: 01/03/2023]
Abstract
OBJECTIVE Insulin-like growth factor-I (IGF-I) is a key regulator of metabolism during altered energy states. The IGF-I system components respond to prolonged caloric restriction but it is not clear if this system responds similarly to acute caloric restriction. The purpose of this study was to characterize the IGF-I system response to acute caloric restriction with a secondary purpose of determining if two isocaloric diets with different ratios of carbohydrate to fat alter the IGF-I system under conditions of caloric balance. MATERIALS/METHODS A double-blind, placebo-controlled crossover design was used in which 27 subjects underwent three, 48-h experimental treatments: 1) caloric restriction 2) carbohydrate and 3) carbohydrate/fat. Blood was sampled periodically (6 time points total) for IGF-I (total and free), IGFBPs1-4, insulin and glucose. ANOVAs were used with significance set at P<0.05. RESULTS Total IGF-I decreased 7% during CR (P=0.051) and remained stable during CHO and CHO/F. Free IGF-I decreased 43% during CR (P<0.05) and remained stable during CHO and CHO/F. IGFBP-1 increased by 445% during CR (P<0.05) compared to CHO and CHO/F with no changes for IGFBP-2, IGFBP-3 and IGFBP-4. There was no change in glucose or insulin during CR over the course of the study. Insulin and glucose increased (P<0.05) after a meal in both the CHO and CHO/F groups with no difference between these two groups. CONCLUSION Our findings indicate that free IGF-I decreases and IGFBP-1 increases during caloric restriction, but they are not altered with diets differing in carbohydrate and fat content. Changes in free IGF-I and IGFBP-1 are sensitive to caloric restriction, and their measurement may be valuable in monitoring the physiological response to refeeding in those consuming suboptimal calories.
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Affiliation(s)
- Paul C Henning
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, MA 01760, USA.
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Giannoulis MG, Martin FC, Nair KS, Umpleby AM, Sonksen P. Hormone replacement therapy and physical function in healthy older men. Time to talk hormones? Endocr Rev 2012; 33:314-77. [PMID: 22433122 PMCID: PMC5393154 DOI: 10.1210/er.2012-1002] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Improving physical function and mobility in a continuously expanding elderly population emerges as a high priority of medicine today. Muscle mass, strength/power, and maximal exercise capacity are major determinants of physical function, and all decline with aging. This contributes to the incidence of frailty and disability observed in older men. Furthermore, it facilitates the accumulation of body fat and development of insulin resistance. Muscle adaptation to exercise is strongly influenced by anabolic endocrine hormones and local load-sensitive autocrine/paracrine growth factors. GH, IGF-I, and testosterone (T) are directly involved in muscle adaptation to exercise because they promote muscle protein synthesis, whereas T and locally expressed IGF-I have been reported to activate muscle stem cells. Although exercise programs improve physical function, in the long-term most older men fail to comply. The GH/IGF-I axis and T levels decline markedly with aging, whereas accumulating evidence supports their indispensable role in maintaining physical function integrity. Several studies have reported that the administration of T improves lean body mass and maximal voluntary strength in healthy older men. On the other hand, most studies have shown that administration of GH alone failed to improve muscle strength despite amelioration of the detrimental somatic changes of aging. Both GH and T are anabolic agents that promote muscle protein synthesis and hypertrophy but work through separate mechanisms, and the combined administration of GH and T, albeit in only a few studies, has resulted in greater efficacy than either hormone alone. Although it is clear that this combined approach is effective, this review concludes that further studies are needed to assess the long-term efficacy and safety of combined hormone replacement therapy in older men before the medical rationale of prescribing hormone replacement therapy for combating the sarcopenia of aging can be established.
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Affiliation(s)
| | - Finbarr C. Martin
- Guy's and St. Thomas' National Health Service Foundation Trust (F.C.M.), and Institute of Gerontology (F.C.M.), King's College, London WC2R 2LS, United Kingdom
| | | | - A. Margot Umpleby
- Department of Human Metabolism, Diabetes, and Metabolic Medicine (A.M.U.), Postgraduate Medical School, University of Surrey, Guildford GU2 7WG, United Kingdom
| | - Peter Sonksen
- St. Thomas' Hospital and King's College (P.S.), London SE1 7EW, United Kingdom; and Southampton University (P.S.), SO17 1BJ, Southampton, United Kingdom
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Hasani-Ranjbar S, Soleymani Far E, Heshmat R, Rajabi H, Kosari H. Time course responses of serum GH, insulin, IGF-1, IGFBP1, and IGFBP3 concentrations after heavy resistance exercise in trained and untrained men. Endocrine 2012; 41:144-51. [PMID: 21983797 DOI: 10.1007/s12020-011-9537-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2011] [Accepted: 08/24/2011] [Indexed: 10/17/2022]
Abstract
To investigate the effect of heavy resistance exercise on IGF-1 system, 19 healthy trained men and 15 healthy untrained men volunteered to participate in this study. The subjects were randomly divided into experimental and control groups. Subjects of experimental groups were forced to perform a heavy resistance exercise with the intensity of 70-80% of 1RM in selected movements. The blood samples were taken from all subjects four times; before (T1), immediately after (T2), 5 (T3), and 8 (T4) hours after exercise. Analysis of data showed that a session of heavy resistance exercise induced significant increase in GH at T2 (P < 0.05) and a significant decrease in insulin at T4 (P < 0.05) and a significant decrease in IGFBP3 at T4 (P < 0.05) in trained group. In untrained group, no significant change in any of the variables was observed. However, the procedure of response in variables was almost similar in two experimental groups. Although, the exercise did not appreciably affect IGF-1 levels, it decreased in all groups at length of time after exercise. In addition, the exercise did not have any notable effect on IGFBP1 levels over time. In conclusion, the findings of this study indicate that the intense resistance exercise can lead to changes in blood concentrations of IGF-1 system components which are observable in blood circulation over time and the amounts of changes depend on subjects' fitness levels and exercise variables.
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Affiliation(s)
- Shirin Hasani-Ranjbar
- Endocrinology & Metabolism Research Institute, Tehran University of Medical Sciences, 5th Floor, Shariati Hospital, North Kargar Ave., 14114, Tehran, Iran.
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Fortes MB, Diment BC, Greeves JP, Casey A, Izard R, Walsh NP. Effects of a daily mixed nutritional supplement on physical performance, body composition, and circulating anabolic hormones during 8 weeks of arduous military training. Appl Physiol Nutr Metab 2011; 36:967-75. [PMID: 22111592 DOI: 10.1139/h11-124] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The aim of this work was to investigate the effect of a daily mixed nutritional supplement upon body composition, physical performance, and circulating anabolic hormones in soldiers undergoing arduous training. Thirty males received either a habitual diet alone (CON, n = 15) or with the addition of a daily mixed supplement (SUP, n = 15) of ∼5.1 MJ·d⁻¹ during 8 weeks of training. Body composition (DEXA), maximal dynamic lift strength (MDLS), and vertical jump (VJ) were assessed, and resting blood samples were collected before and after training. Blood analysis included insulin-like growth factors (IGF-1, IGF BP-1, and IGF BP-3), testosterone, and cortisol. There were no group differences at baseline. Body mass loss (mean ± SD) (CON 5.0 ± 2.3, SUP 1.6 ± 1.5 kg), lean mass loss (CON 2.0 ± 1.5, SUP 0.7 ± 1.5 kg), and fat mass loss (CON 3.0 ± 1.6, SUP 0.9 ± 1.8 kg) were significantly blunted by SUP. CON experienced significant decrements in MDLS (14%), VJ (10%), and explosive leg power (11%) that were prevented by SUP. Military training significantly reduced circulating IGF-1 (28%), testosterone (19%), and the testosterone:cortisol ratio (24%) with no effect of SUP. Circulating IGF BP-1 concentration and cortisol remained unchanged throughout, although SUP abolished the significant decrease in circulating IGF BP-3 (20%) on CON. In conclusion, a daily mixed nutritional supplement attenuated decreases in body mass and lean mass and prevented the decrease in physical performance during an arduous military training program.
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Affiliation(s)
- Matthew B Fortes
- Extremes Research Group, Bangor University, Bangor, Gwynedd LL57 2PZ, UK
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Scofield DE, McClung HL, McClung JP, Kraemer WJ, Rarick KR, Pierce JR, Cloutier GJ, Fielding RA, Matheny RW, Young AJ, Nindl BC. A novel, noninvasive transdermal fluid sampling methodology: IGF-I measurement following exercise. Am J Physiol Regul Integr Comp Physiol 2011; 300:R1326-32. [DOI: 10.1152/ajpregu.00313.2010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
This study tested the hypothesis that transdermal fluid (TDF) provides a more sensitive and accurate measure of exercise-induced increases in insulin-like growth factor-I (IGF-I) than serum, and that these increases are detectable proximal, but not distal, to the exercising muscle. A novel, noninvasive methodology was used to collect TDF, followed by sampling of total IGF-I (tIGF-I) and free IGF-I (fIGF-I) in TDF and serum following an acute bout of exercise. Experiment 1: eight men (23 ± 3 yrs, 79 ± 7 kg) underwent two conditions (resting and 60 min of cycling exercise at 60% V̇o2peak) in which serum and forearm TDF were collected for comparison. There were no significant changes in tIGF-I or fIGF-I in TDF obtained from the forearm or from serum following exercise ( P > 0.05); however, the proportion of fIGF-I to tIGF-I in TDF was approximately fourfold greater than that of serum ( P ≤ 0.05). These data suggest that changes in TDF IGF-I are not evident when TDF is sampled distal from the working tissue. To determine whether exercise-induced increases in local IGF-I could be detected when TDF was sampled directly over the active muscle group, we performed a second experiment. Experiment 2: fourteen subjects (22 ± 4 yr, 68 ± 11 kg) underwent an acute plyometric exercise condition consisting of 10 sets of 10 plyometric jumps with 2-min rest between sets. We observed a significant increase in TDF tIGF-I following exercise ( P ≤ 0.05) but no change in serum tIGF-I ( P > 0.05). Overall, these data suggest that TDF may provide a noninvasive means of monitoring acute exercise-induced changes in local IGF-I when sampled in proximity to exercising muscles. Moreover, our finding that the proportion of free to tIGF-I was greater in TDF than in serum suggests that changes in local IGF-I may be captured more readily using this system.
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Affiliation(s)
| | - H. L. McClung
- Nutrition Divisions, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - J. P. McClung
- Nutrition Divisions, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - W. J. Kraemer
- Human Performance Laboratory, Departments of Kinesiology and Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut; and
| | | | | | - G. J. Cloutier
- Tufts University, Nutrition, Exercise Physiology, Sarcopenia Laboratory, Boston, Massachusetts
| | - R. A. Fielding
- Tufts University, Nutrition, Exercise Physiology, Sarcopenia Laboratory, Boston, Massachusetts
| | | | - A. J. Young
- Nutrition Divisions, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts
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Tanskanen MM, Kyröläinen H, Uusitalo AL, Huovinen J, Nissilä J, Kinnunen H, Atalay M, Häkkinen K. Serum Sex Hormone–Binding Globulin and Cortisol Concentrations are Associated With Overreaching During Strenuous Military Training. J Strength Cond Res 2011; 25:787-97. [DOI: 10.1519/jsc.0b013e3181c1fa5d] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Nindl BC, Alemany JA, Tuckow AP, Rarick KR, Staab JS, Kraemer WJ, Maresh CM, Spiering BA, Hatfield DL, Flyvbjerg A, Frystyk J. Circulating bioactive and immunoreactive IGF-I remain stable in women, despite physical fitness improvements after 8 weeks of resistance, aerobic, and combined exercise training. J Appl Physiol (1985) 2010; 109:112-20. [DOI: 10.1152/japplphysiol.00025.2010] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Insulin-like growth factor-I (IGF-I) is regulated by a number of IGF-binding proteins (IGFBPs) and proteases that influence IGF-I bioactivity. A specific IGF-I kinase receptor activation assay (KIRA) has been developed that determines the ability of IGF-I to activate the IGF-I receptor by quantification of intracellular receptor autophosphorylation on IGF-I binding. KIRA-assessed IGF-I bioactivity has not been utilized within the context of chronic exercise training paradigms. This study measured total and free immunoreactive IGF-I, bioactive IGF-I, and IGFBP-1, -2, and -3 before (Pre), during (Mid), and after (Post) 8 wk of exercise training in young, healthy women, who were randomized into one of four groups: control ( n = 10), resistance ( n = 18), aerobic ( n = 13), and combined ( n = 15) exercise training. The training programs were effective in improving physical fitness specific to the exercise mode engaged in: increases were observed for lean mass (∼2%), aerobic fitness (6–7%), and upper (20–24%) and lower (15–48%) body strength (all P values < 0.05). By contrast, no time, group, or interaction effects were observed for the circulating IGF-I system, as immunoreactive total (Pre = 264 ± 16 μg/l; Mid = 268 ± 17 μg/l; Post = 271 ± 17 μg/l), free (Pre = 0.70 ± 0.1 μg/l; Mid = 0.63 ± 0.1 μg/l; Post = 0.63 ± 0.2 μg/l) and bioactive (Pre = 2.35 ± 0.3 μg/l; Mid = 2.25 ± 0.3 μg/l; Post = 2.33 ± 0.3 μg/l) IGF-I were unchanged throughout the study. All IGFBP measures were also unchanged. We conclude that increased lean mass, aerobic fitness, and upper and lower body strength resulting from an 8-wk exercise training programs can occur without concomitant increases in either circulating bioactive or immunoreactive IGF-I, as well as associated IGFBPs. In terms of reflecting positive anabolic neuromuscular outcomes, these data do not support a role for endocrine-derived IGF-I.
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Affiliation(s)
- Bradley C. Nindl
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - Joseph A. Alemany
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - Alexander P. Tuckow
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - Kevin R. Rarick
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - Jeffery S. Staab
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, Massachusetts
| | - William J. Kraemer
- Human Performance Laboratory, University of Connecticut, Storrs, Connecticut; and
| | - Carl M. Maresh
- Human Performance Laboratory, University of Connecticut, Storrs, Connecticut; and
| | - Barry A. Spiering
- Human Performance Laboratory, University of Connecticut, Storrs, Connecticut; and
| | - Disa L. Hatfield
- Human Performance Laboratory, University of Connecticut, Storrs, Connecticut; and
| | - Allan Flyvbjerg
- Medical Research Laboratories, Clinical Institute of Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Jan Frystyk
- Medical Research Laboratories, Clinical Institute of Medicine, Aarhus University Hospital, Aarhus, Denmark
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Weeks SR, McAuliffe CL, DuRussel D, Pasquina PF. Physiological and Psychological Fatigue in Extreme Conditions: The Military Example. PM R 2010; 2:438-41. [DOI: 10.1016/j.pmrj.2010.03.023] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2009] [Accepted: 03/21/2010] [Indexed: 11/25/2022]
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NINDL BRADLEYC. Insulin-Like Growth Factor-I, Physical Activity, and Control of Cellular Anabolism. Med Sci Sports Exerc 2010; 42:35-8. [DOI: 10.1249/mss.0b013e3181b07c39] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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NINDL BRADLEYC, PIERCE JOSEPHR. Insulin-Like Growth Factor I as a Biomarker of Health, Fitness, and Training Status. Med Sci Sports Exerc 2010; 42:39-49. [DOI: 10.1249/mss.0b013e3181b07c4d] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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NINDL BRADLEYC, ALEMANY JOSEPHA, TUCKOW ALEXANDERP, KELLOGG MARKD, SHARP MARILYNA, PATTON JOHNF. Effects of Exercise Mode and Duration on 24-h IGF-I System Recovery Responses. Med Sci Sports Exerc 2009; 41:1261-70. [DOI: 10.1249/mss.0b013e318197125c] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Nindl BC. Insulin-like growth factor-I as a candidate metabolic biomarker: military relevance and future directions for measurement. J Diabetes Sci Technol 2009; 3:371-6. [PMID: 20144370 PMCID: PMC2771506 DOI: 10.1177/193229680900300220] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Insulin-like growth factor (IGF)-I is a ubiquitous peptide hormone involved in a host of critical physiological processes (e.g., protein synthesis and glucose homeostasis) and has been suggested to be a biomarker reflecting health and metabolic status. In most cases (muscle, bone, tendon, body composition, and cognitive function), elevated IGF-I concentrations are considered beneficial; however, cancer remains a notable exception. While the fact that both increased and decreased IGF-I can be considered reflective of favorable and beneficial health outcomes may appear as a paradox, it is important to emphasize that, in both cases, measured IGF-I concentrations do offer important insight into physiological processes. The effects of military operational field training on the circulating IGF-I system are discussed within the context of novel measurement technologies that (1) are field expedient and (2) provide more meaningful information. Prospective experimental approaches involving physical activity that sample and measure IGF-I in the body's various biocompartments will provide greater insight into the complex role that IGF-I possesses. Minimally invasive technologies that are field expedient, cost-effective, and allow for continuous and real-time feedback will have the greatest likelihood of being adapted and used in military environments.
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Affiliation(s)
- Bradley C Nindl
- Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts, USA.
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Alemany JA, Nindl BC, Kellogg MD, Tharion WJ, Young AJ, Montain SJ. Effects of dietary protein content on IGF-I, testosterone, and body composition during 8 days of severe energy deficit and arduous physical activity. J Appl Physiol (1985) 2008; 105:58-64. [DOI: 10.1152/japplphysiol.00005.2008] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Energy restriction coupled with high energy expenditure from arduous work is associated with an altered insulin-like growth factor-I (IGF-I) system and androgens that are coincident with losses of fat-free mass. The aim of this study was to determine the effects of two levels of dietary protein content and its effects on IGF-I, androgens, and losses of fat-free mass accompanying energy deficit. We hypothesized that higher dietary protein content would attenuate the decline of anabolic hormones and, thus, prevent losses of fat-free mass. Thirty-four men [24 (SD 0.3) yr, 180.1 (SD 1.1) cm, and 83.0 (SD 1.4) kg] participated in an 8-day military exercise characterized by high energy expenditure (16.5 MJ/day), low energy intake (6.5 MJ/day), and sleep deprivation (4 h/24 h) and were randomly divided into two dietary groups: 0.9 and 0.5 g/kg dietary protein intake. IGF-I system analytes, androgens, and body composition were assessed before and on days 4 and 8 of the intervention. Total, free, and nonternary IGF-I and testosterone declined 50%, 64%, 55%, and 45%, respectively, with similar reductions in both groups. There was, however, a diet × time interaction on day 8 for total IGF-I and sex hormone-binding globulin. Decreases in body mass (3.2 kg), fat-free mass (1.2 kg), fat mass (2.0 kg), and percent body fat (1.5%) were similar in both groups ( P = 0.01). Dietary protein content of 0.5 and 0.9 g/kg minimally attenuated the decline of IGF-I, the androgenic system, and fat-free mass during 8 days of negative energy balance associated with high energy expenditure and low energy intake.
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Kyröläinen H, Karinkanta J, Santtila M, Koski H, Mäntysaari M, Pullinen T. Hormonal responses during a prolonged military field exercise with variable exercise intensity. Eur J Appl Physiol 2007; 102:539-46. [DOI: 10.1007/s00421-007-0619-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/07/2007] [Indexed: 11/24/2022]
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Rarick KR, Pikosky MA, Grediagin A, Smith TJ, Glickman EL, Alemany JA, Staab JS, Young AJ, Nindl BC. Energy flux, more so than energy balance, protein intake, or fitness level, influences insulin-like growth factor-I system responses during 7 days of increased physical activity. J Appl Physiol (1985) 2007; 103:1613-21. [PMID: 17702838 DOI: 10.1152/japplphysiol.00179.2007] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose of this study was to determine the impact of dietary factors and exercise-associated factors on the response of IGF-I and its binding proteins (IGFBPs) during a period of increased physical activity. Twenty-nine men completed a 4-day ( days 1–4) baseline period of a controlled energy balanced diet while maintaining their normal physical activity level followed by 7 days ( days 5–11) of a 1,000 kcal/day increase in physical activity above their normal activity levels. Two subject groups, one sedentary (Sed, mean V̇o2peak: 39 ml·kg−1·min−1, n = 7) and one fit (FIT1, mean V̇o2peak: 56 ml·kg−1·min−1, n = 8) increased energy intake to maintain energy balance throughout the 7-day intervention. In two other fit subject groups (FIT2, n = 7 and FIT3, n = 7), energy intake remained at baseline resulting in a 1,000 kcal/day exercise-induced energy deficit. Of these, FIT2 received an adequate protein diet (0.9 g/kg), and FIT3 received a high-protein diet (1.8 g/kg). For all four groups, IGF-I, IGFBP-3, and the acid labile subunit (ALS) were significantly decreased by day 11 (27 ± 4%, 10 ± 2%, and 19 ± 4%, respectively) and IGFBP-2 significantly increased by 49 ± 21% following day 3. IGFBP-1 significantly increased only in the two negative energy balance groups, FIT2 (38 ± 6%) and FIT3 (46 ± 8%). Differences in initial fitness level and dietary protein intake did not alter the IGF-I system response to an acute increase in physical activity. Decreases in IGF-I were observed during a moderate increase in physical activity despite maintaining energy balance, suggesting that currently unexplained exercise-associated mechanisms, such as increased energy flux, regulate IGF-I independent of energy deficit.
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Affiliation(s)
- Kevin R Rarick
- Military Performance Division, U. S. Army Research Institute of Environmental Medicine, Natick, MA 01760, USA
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Nindl BC, Alemany JA, Kellogg MD, Rood J, Allison SA, Young AJ, Montain SJ. Utility of circulating IGF-I as a biomarker for assessing body composition changes in men during periods of high physical activity superimposed upon energy and sleep restriction. J Appl Physiol (1985) 2007; 103:340-6. [PMID: 17412783 DOI: 10.1152/japplphysiol.01321.2006] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Insulin-like growth factor (IGF)-I is a biomarker that may have greater utility than other conventional nutritional biomarkers in assessing nutritional, health, and fitness status. We hypothesized that the IGF-I system would directionally track a short-term energy deficit and would be more related to changes in body composition than other nutritional biomarkers. Thirty-five healthy men (24 ± 0.3 yr) underwent 8 days of exercise and energy imbalance. Total and free IGF-I, IGF binding proteins-1, -2, and -3, the acid labile subunit, transferrin, ferritin, retinol binding protein, prealbumin, testosterone, triiodothyronine, thyroxine, and leptin responses were measured. Dual-energy X-ray absorptiometry assessed changes in body mass and composition. Repeated-measures ANOVA, correlation analysis, and receiver operator characteristic curves were used for statistical analyses ( P ≤ 0.05). Body mass (−3.8%), fat-free mass (−2.2%), and fat mass (−12.9%) all decreased. Total and free IGF-I, IGF binding protein-3, and the acid labile subunit and prealbumin, but not transferrin, retinol-binding protein, and ferritin, directionally tracked the energy deficit and losses in body composition. The correlation ( r = 0.43) between changes in free IGF-I and body and fat-free mass was the only significant association observed. Receiver operator characteristic curve analysis revealed that a baseline value < 1.67 for the molar volume ratio of IGF-I to acid labile subunit had an area under the curve of 0.745 and was a significant discriminator for those subjects losing >5% body mass. The IGF-I system is an important adjunct in the overall assessment of adaptation to stress imposed by high levels of physical activity superimposed on energy and sleep restriction and is more closely associated with losses in body mass and fat-free mass than other conventional nutritional biomarkers.
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Affiliation(s)
- Bradley C Nindl
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, MA 01760-5007, USA.
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Bricout VA, Guinot M, Duclos M, Koulmann N, Serrurier B, Brun JF, Flore P, Chatard JC, Bigard X, Favre-Juvin A. Position de consensus: apport des examens biologiques dans le diagnostic de surentraînement. Sci Sports 2006. [DOI: 10.1016/j.scispo.2006.09.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Abstract
PURPOSE OF REVIEW The increase in obesity in developed societies drives interest in the interplay of energy intake, metabolic energy expenditure, and body energy stores. A better understanding of energy management in physically active and undernourished humans should help guide strategies to manage obesity safely and effectively. This review focuses on field studies of men and women engaged in prolonged strenuous activities, ranging from ranger training to extreme expeditions. RECENT FINDINGS Although scientifically unconventional and limited, field studies of exercise and food deprivation have yielded interesting findings: 4-5% body fat is the normal lower limit to fat reserves in physically active underfed young adult men, and in response to exercise and underfeeding, women used more fat mass and less fat-free mass to meet metabolic fuel requirements. SUMMARY Field studies have shown that fat energy reserves in young adult men can be estimated as percentage body fat minus 5%, and initial body fat mass has a significant positive influence on fat oxidation rates per kilogram of fat-free mass during rapid weight loss associated with underfeeding and exercise. Data logging pedometers, activity monitors, global positioning systems, and wireless body and personal-area networks promise to make it easier to study and care for free-living humans.
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Affiliation(s)
- Reed W Hoyt
- Biophysics and Biomedical Modeling Division, US Army Research Institute of Environmental Medicine, Kansas Street, Natick, MA 01760, USA.
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Ormsbee M, Clapper JA, Clapper J, Vukovich MD. Moderate changes in energy balance combined with exercise do not alter insulin-like growth factor I or insulin-like growth factor binding protein 3. Nutr Res 2006. [DOI: 10.1016/j.nutres.2006.08.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Nindl BC, Tuckow AP, Alemany JA, Harman EA, Rarick KR, Staab JS, Faupel ML, Khosravi MJ. Minimally invasive sampling of transdermal body fluid for the purpose of measuring insulin-like growth factor-I during exercise training. Diabetes Technol Ther 2006; 8:244-52. [PMID: 16734553 DOI: 10.1089/dia.2006.8.244] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Insulin-like growth factor-I (IGF-I) is a ubiquitous hormone that is secreted in both an endocrine and an autocrine/paracrine manner. IGF-I has conventionally been measured in serum; however, transdermal body fluid (TDF) remains as an unexplored biocompartment in which IGF-I also resides and may be more biologically relevant because of its proximity to tissues and cells. The purpose of this study was to compare IGF-I in serum versus IGF-I in TDF before and after 8 weeks of physical training. Twenty-eight healthy men (28 +/- 5 years old, 176 +/- 8 cm tall, weighing 83 +/- 11 kg) had TDF obtained by a novel, minimally invasive method that included the application of continuous vacuum pressure on forearm skin perforated with tiny micropores created by a focused beam from a laser system and also had blood obtained by venipuncture. An enzyme-linked immunosorbent assay measured total IGF-I concentrations. A repeated-measures analysis of variance (biocompartment x time) and Pearson Product Moment Correlation coefficients (P < or = 0.05) were used for statistical analyses. Data are presented as mean +/- SE. Total TDF IGF-I was significantly lower than serum IGF-I both before (TDF, 91 +/- 6 ng/mL; serum, 375 +/- 17 ng/mL) and after (TDF, 83 +/- 5 ng/mL; serum, 363 +/- 19 ng/mL) the exercise training. Serum and TDF IGF-I values were not significantly different pre- to post-training. Serum and TDF IGF-I levels were significantly correlated pre-training (r = 0.41), but not post-training (r = 0.34). The percent change between serum and TDF was not correlated (r = 0.09). This study has demonstrated that total IGF-I can be sampled and measured in TDF via a minimally invasive manner and is appreciably (approximately 76%) less than total IGF-I measured in serum. Additionally, the IGF-I measurements in these two biocompartments were not closely associated, possibly indicating an uncoupled, rather than a linked, regulation of IGF-I among the body's biocompartments.
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Affiliation(s)
- Bradley C Nindl
- Military Performance Division, U.S. Army Research Institute of Environmental Medicine, Natick, Massachusetts 01760, USA.
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Nindl BC, Rarick KR, Castellani JW, Tuckow AP, Patton JF, Young AJ, Montain SJ. Altered secretion of growth hormone and luteinizing hormone after 84 h of sustained physical exertion superimposed on caloric and sleep restriction. J Appl Physiol (1985) 2006; 100:120-8. [PMID: 16141374 DOI: 10.1152/japplphysiol.01415.2004] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The pulsatile release of growth hormone (GH) and luteinizing hormone (LH) from the anterior pituitary gland is integral for signaling secretion of insulin-like growth factor (IGF)-I and testosterone, respectively. This study examined the hypothesis that 84 h of sustained physical exertion with caloric and sleep restriction alters the secretion of GH and LH. Ten male soldiers [22 yr (SD 3), 183 cm (SD 7), 87 kg (SD 8)] had blood drawn overnight from 1800 to 0600 every 20 min for GH, LH, and leptin and every 2 h for IGF-I (total and free), IGF binding proteins-1 and -3, testosterone (total and free), glucose, and free fatty acids during a control week and after 84 h of military operational stress. Time-series cluster and deconvolution analyses assessed the secretion parameters of GH and LH. Significant results ( P ≤ 0.05) were as follows: body mass (−3%), fat-free mass (−2.3%), and fat mass (−7.3%) declined after military operational stress. GH and LH secretion burst amplitude (∼50%) and overnight pulsatile secretion (∼50%), IGF binding protein-1 (+67%), and free fatty acids (+33%) increased, whereas leptin (−47%), total (−27%) and free IGF-I (−32%), total (−24%) and free testosterone (−30%), and IGF binding protein-3 (−6%) decreased. GH and LH pulse number were unaffected. Because GH and LH positively regulate IGF-I and testosterone, these data imply that the physiological strain induced a certain degree of peripheral resistance. During periods of energy deficiency, amplitude modulation of GH and LH pulses may precede alterations in pulse numbers.
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Affiliation(s)
- Bradley C Nindl
- Military Performance Division, United States Army Research Institute of Environmental Medicine, Natick, Massachusetts 01760, USA.
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Ballard TL, Clapper JA, Specker BL, Binkley TL, Vukovich MD. Effect of protein supplementation during a 6-mo strength and conditioning program on insulin-like growth factor I and markers of bone turnover in young adults. Am J Clin Nutr 2005; 81:1442-8. [PMID: 15941900 DOI: 10.1093/ajcn/81.6.1442] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Exercise is beneficial for bone when adequate nutrition is provided. The role of protein consumption in bone health, however, is controversial. OBJECTIVE The objective was to ascertain the effect of high protein intake on insulin-like growth factor I (IGF-I) and markers of bone turnover during 6 mo of exercise training. DESIGN Fifty-one subjects aged 18-25 y (28 men, 23 women) received a protein supplement (42 g protein, 24 g carbohydrate, 2 g fat) or a carbohydrate supplement (70 g carbohydrate) twice daily. Exercise consisted of alternating resistance training and running 5 times/wk. Plasma concentrations of IGF-I, insulin-like growth factor-binding protein 3, serum bone alkaline phosphatase, and urinary N-telopeptide collagen crosslink (NTx) concentrations were measured at 0, 3, and 6 mo after 24 h without exercise and a 12-h fast. RESULTS Three-day diet records indicated no difference in energy intake between the groups. Average protein intakes after supplementation began in the protein and carbohydrate groups were 2.2 +/- 0.1 and 1.1 +/- 0.1 g/kg, respectively (P < 0.001). The increase in plasma IGF-I was greater in the protein group than in the carbohydrate group (time x supplement interaction, P = 0.01). There were no significant changes over time or significant differences by supplement in plasma insulin-like growth factor-binding protein 3 (44 and 40 kDa). Serum bone alkaline phosphatase increased significantly over time (P = 0.04) and tended to be higher in the protein group than in the carbohydrate group (P = 0.06). NTx concentrations changed over time (time and time squared; P < 0.01 for both) and were greater in the protein group than in the carbohydrate group (P = 0.04). Men had higher NTx concentrations than did women (74.6 +/- 3.4 and 60.0 +/- 3.8 nmol/mmol creatinine; P = 0.005). CONCLUSION Protein supplementation during a strength and conditioning program resulted in changes in IGF-I concentrations.
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Affiliation(s)
- Tasha Lp Ballard
- Applied Physiology Laboratory, South Dakota State University, Brookings, SD 57007, USA
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González-Ortiz M, Martínez-Abundis E. Impact of Sleep Deprivation on Insulin Secretion, Insulin Sensitivity, and Other Hormonal Regulations. Metab Syndr Relat Disord 2005; 3:3-7. [PMID: 18370703 DOI: 10.1089/met.2005.3.3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Manuel González-Ortiz
- Medical Research Unit in Clinical Epidemiology, West National Medical Center, Mexican Institute of Social Security, Guadalajara, Mexico
| | - Esperanza Martínez-Abundis
- Medical Research Unit in Clinical Epidemiology, West National Medical Center, Mexican Institute of Social Security, Guadalajara, Mexico
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Nindl BC, Headley SA, Tuckow AP, Pandorf CE, Diamandi A, Khosravi MJ, Welles R, Jones M, Germain M. IGF-I system responses during 12 weeks of resistance training in end-stage renal disease patients. Growth Horm IGF Res 2004; 14:245-250. [PMID: 15125886 DOI: 10.1016/j.ghir.2004.01.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2003] [Revised: 01/03/2004] [Accepted: 01/15/2004] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To examine the hypothesis that 12 weeks of resistance training would alter circulating concentrations of IGF-I system components in end-stage renal disease (ESRD) patients. DESIGN Ten ESRD patients underwent 12 weeks of resistance training after a 6 week control period and had morning fasted blood drawn on four occasions (weeks - 6, 0, 6, 12). Immunoassays were performed for serum total and free IGF-I, IGF binding proteins (IGFBPs) 2 and 3, and the acid labile subunit (ALS). Immunoaffinity depletion of ALS-based complexes allowed measurement of non-ternary (i.e., binary) IGF-I and IGFBP-3. RESULTS Significant improvements in strength and functional performance were observed. All IGF-I measures were stable during the control period and no changes were observed for the first 6 weeks of resistance training. At week 12, total IGF-I (-15.4+/-28.9%), ternary IGF-I (-16.4+/-36.7%), and the IGF-I/IGFBP-3 ratio had significantly (p < or = 0.05) declined from week 0 values. No changes were observed for free IGF-I, IGFBPs 2 and 3, or the acid labile subunit. The proportion of IGF-I in ternary ( approximately 76.3+/-6.8%), non-ternary ( approximately 22.5+/-6.6%), and free ( approximately 1.2+/-0.5%) forms remained constant throughout the training. CONCLUSIONS 12 weeks of resistance training in ESRD patients induced a decline in total IGF-I, but did not alter the proportion of IGF-I circulating in free, ternary or non-ternary molecular complexes. The decline in IGF-I occurs in the presence of positive training adaptations on physical performance and we conclude that this response pattern appears to be reflective of favorable neuromuscular anabolic adaptations.
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Affiliation(s)
- Bradley C Nindl
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, MA 01760, USA.
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