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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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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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Andersen ML, Gozal D, Pires GN, Tufik S. Exploring the potential relationships among obstructive sleep apnea, erectile dysfunction, and gut microbiota: a narrative review. Sex Med Rev 2023; 12:76-86. [PMID: 37385976 DOI: 10.1093/sxmrev/qead026] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/15/2023] [Accepted: 05/16/2023] [Indexed: 07/01/2023]
Abstract
INTRODUCTION Poor sleep quality is closely associated with comorbidities affecting a multitude of organ systems. Among the sleep disorders in the population, there has recently been an increase in the prevalence of obstructive sleep apnea (OSA), which has particularly affected men. The intermittent hypoxia and sleep fragmentation associated with OSA can result in the manifestation or aggravation of a number of pathophysiologic conditions, including the impairment of reproductive function in men and women. In this context, erectile dysfunction (ED) is of particular concern. Other consequences of OSA are changes in the gastrointestinal microbiota, with the resultant dysbiosis having potentially harmful consequences that promote downstream exacerbation of various comorbidities. OBJECTIVES This narrative review aims to explore the potential relationships among ED, gut microbiota, and OSA. METHODS A search of the relevant literature was performed in the PubMed, Embase, Medline, and Web of Science databases. RESULTS Sleep is important for regulating the body's functions, and sleep deprivation can negatively affect health. OSA can damage organic functions, including reproductive function, and can lead to ED. Restoring the microbiota and improving sleep can help to improve sexual function or reverse ED and enhance other associated conditions mediated through the gut-brain axis relationship. Probiotics and prebiotics can be used as supportive strategies in the prevention and treatment of OSA, as they help to reduce systemic inflammation and improve intestinal barrier function. CONCLUSION A good diet, a healthy lifestyle, and proper bowel function are essential in controlling depression and several other pathologies. Modulating the gut microbiota through probiotics and prebiotics can provide a viable strategy for developing new therapeutic options in treating many conditions. A better understanding of these a priori unrelated phenomena would foster our understanding of the effects of OSA on human fertility and how changes in gut microbiota may play a role.
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Affiliation(s)
- Monica Levy Andersen
- Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, 04024-002, Brazil
| | - David Gozal
- Department of Child Health and the Child Health Research Institute, University of Missouri School of Medicine, Columbia, MO 65212, United States
| | - Gabriel Natan Pires
- Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, 04024-002, Brazil
| | - Sergio Tufik
- Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, 04024-002, Brazil
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Stellingwerff T, Mountjoy M, McCluskey WT, Ackerman KE, Verhagen E, Heikura IA. Review of the scientific rationale, development and validation of the International Olympic Committee Relative Energy Deficiency in Sport Clinical Assessment Tool: V.2 (IOC REDs CAT2)-by a subgroup of the IOC consensus on REDs. Br J Sports Med 2023; 57:1109-1118. [PMID: 37752002 DOI: 10.1136/bjsports-2023-106914] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/14/2023] [Indexed: 09/28/2023]
Abstract
Relative Energy Deficiency in Sport (REDs) has various different risk factors, numerous signs and symptoms and is heavily influenced by one's environment. Accordingly, there is no singular validated diagnostic test. This 2023 International Olympic Committee's REDs Clinical Assessment Tool-V.2 (IOC REDs CAT2) implements a three-step process of: (1) initial screening; (2) severity/risk stratification based on any identified REDs signs/symptoms (primary and secondary indicators) and (3) a physician-led final diagnosis and treatment plan developed with the athlete, coach and their entire health and performance team. The CAT2 also introduces a more clinically nuanced four-level traffic-light (green, yellow, orange and red) severity/risk stratification with associated sport participation guidelines. Various REDs primary and secondary indicators have been identified and 'weighted' in terms of scientific support, clinical severity/risk and methodological validity and usability, allowing for objective scoring of athletes based on the presence or absence of each indicator. Early draft versions of the CAT2 were developed with associated athlete-testing, feedback and refinement, followed by REDs expert validation via voting statements (ie, online questionnaire to assess agreement on each indicator). Physician and practitioner validity and usability assessments were also implemented. The aim of the IOC REDs CAT2 is to assist qualified clinical professionals in the early and accurate diagnosis of REDs, with an appropriate clinical severity and risk assessment, in order to protect athlete health and prevent prolonged and irreversible outcomes of REDs.
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Affiliation(s)
- Trent Stellingwerff
- Canadian Sport Institute Pacific, Victoria, British Columbia, Canada
- Exercise Science, Physical & Health Education, University of Victoria, Victoria, British Columbia, Canada
| | - Margo Mountjoy
- Association for Summer Olympic International Federations (ASOIF), Lausanne, Switzerland
- Department of Family Medicine, McMaster University, Hamilton, Ontario, Canada
| | | | - Kathryn E Ackerman
- Wu Tsai Female Athlete Program, Division of Sports Medicine, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Evert Verhagen
- Amsterdam Collaboration on Health and Safety in Sports and Department of Public and Occupational Health, VU University Medical Centre Amsterdam, Amsterdam, The Netherlands
| | - Ida A Heikura
- Canadian Sport Institute Pacific, Victoria, British Columbia, Canada
- Exercise Science, Physical & Health Education, University of Victoria, Victoria, British Columbia, Canada
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Mountjoy M, Ackerman KE, Bailey DM, Burke LM, Constantini N, Hackney AC, Heikura IA, Melin A, Pensgaard AM, Stellingwerff T, Sundgot-Borgen JK, Torstveit MK, Jacobsen AU, Verhagen E, Budgett R, Engebretsen L, Erdener U. 2023 International Olympic Committee's (IOC) consensus statement on Relative Energy Deficiency in Sport (REDs). Br J Sports Med 2023; 57:1073-1097. [PMID: 37752011 DOI: 10.1136/bjsports-2023-106994] [Citation(s) in RCA: 47] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/20/2023] [Indexed: 09/28/2023]
Abstract
Relative Energy Deficiency in Sport (REDs) was first introduced in 2014 by the International Olympic Committee's expert writing panel, identifying a syndrome of deleterious health and performance outcomes experienced by female and male athletes exposed to low energy availability (LEA; inadequate energy intake in relation to exercise energy expenditure). Since the 2018 REDs consensus, there have been >170 original research publications advancing the field of REDs science, including emerging data demonstrating the growing role of low carbohydrate availability, further evidence of the interplay between mental health and REDs and more data elucidating the impact of LEA in males. Our knowledge of REDs signs and symptoms has resulted in updated Health and Performance Conceptual Models and the development of a novel Physiological Model. This Physiological Model is designed to demonstrate the complexity of either problematic or adaptable LEA exposure, coupled with individual moderating factors, leading to changes in health and performance outcomes. Guidelines for safe and effective body composition assessment to help prevent REDs are also outlined. A new REDs Clinical Assessment Tool-Version 2 is introduced to facilitate the detection and clinical diagnosis of REDs based on accumulated severity and risk stratification, with associated training and competition recommendations. Prevention and treatment principles of REDs are presented to encourage best practices for sports organisations and clinicians. Finally, methodological best practices for REDs research are outlined to stimulate future high-quality research to address important knowledge gaps.
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Affiliation(s)
- Margo Mountjoy
- Family Medicine, McMaster University Michael G DeGroote School of Medicine, Waterloo, Ontario, Canada
- Games Group, International Olympic Committee, Lausanne, Switzerland
| | - Kathryn E Ackerman
- Wu Tsai Female Athlete Program, Harvard Medical School, Boston Children's Hospital, Boston, Massachusetts, USA
| | | | - Louise M Burke
- Mary MacKillop Institute for Health Research, Australian Catholic University, Melbourne, Victoria, Australia
| | - Naama Constantini
- Sports Medicine Center, Shaare Zedek Medical Center, The Hebrew University, Jerusalem, Israel
| | - Anthony C Hackney
- Exercise and Sport Science, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Ida Aliisa Heikura
- Canada Sport Institute Pacific, Victoria, British Columbia, Canada
- Exercise Science, Physical & Health Education, University of Victoria, Victoria, British Columbia, Canada
| | - Anna Melin
- Department of Sport Science - Swedish Olympic Committee Research Fellow, Linnaeus University, Kalmar, Sweden
| | - Anne Marte Pensgaard
- Department of Sport and Social Sciences, Norwegian School of Sports Sciences, Oslo, Norway
| | - Trent Stellingwerff
- Canada Sport Institute Pacific, Victoria, British Columbia, Canada
- Exercise Science, Physical & Health Education, University of Victoria, Victoria, British Columbia, Canada
| | | | | | | | - Evert Verhagen
- Amsterdam Collaboration on Health & Safety in Sports, Department of Public and Occupational Health, Amsterdam Movement Science, Amsterdam UMC Locatie VUmc, Amsterdam, The Netherlands
| | - Richard Budgett
- Medical and Scientific Department, International Olympic Committee, Lausanne, Switzerland
| | - Lars Engebretsen
- Medical and Scientific Department, International Olympic Committee, Lausanne, Switzerland
| | - Uğur Erdener
- Department of Ophthalmology, Hacettepe University, Ankara, Turkey
- World Archery, Lausanne, Switzerland
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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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Alvarenga TA, Fernandes GL, Bittencourt LR, Tufik S, Andersen ML. The effects of sleep deprivation and obstructive sleep apnea syndrome on male reproductive function: a multi-arm randomised trial. J Sleep Res 2023; 32:e13664. [PMID: 35670262 DOI: 10.1111/jsr.13664] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Revised: 04/25/2022] [Accepted: 05/17/2022] [Indexed: 02/03/2023]
Abstract
Sleep is essential for the maintenance of health and systemic homeostasis. Decreased sleep time and sleep quality have been associated with a wide range of diseases. To evaluate the effects of obstructive sleep apnea (OSA) and total or selective rapid eye movement (REM) sleep deprivation on male reproductive function, we performed a three-arm parallel study with one pre-defined OSA group and a group of healthy volunteers who were then randomised into total or REM sleep deprivation groups. Questionnaires were completed and overnight polysomnography was undertaken, and blood and sperm samples were collected at the Sleep Institute, São Paulo, Brazil. OSA was diagnosed using questionnaires and polysomnography. Male sexual function was assessed through the questionnaires, blood tests, and semen samples. Data showed an association between OSA and lower circulating levels of total and free testosterone and high-density lipoproteins, as well as a lower proportion of healthy sperm cells and decreased sperm concentration, in comparison to volunteers. Volunteers subjected to either total or REM sleep deprivation had increased circulating levels of thyroid-stimulating hormone, insulin, and higher homeostatic model assessment of insulin resistance (HOMA-IR) values. Both sleep-deprived groups also shown decreased cholesterol, and low-density lipoproteins when compared to their baseline levels, but had no alterations in their spermograms. We observed a reduction in total testosterone following total sleep deprivation, but no effect after REM sleep deprivation. OSA was associated with a hormonal imbalance, which is probably linked with impaired reproductive function and associated comorbidities, such as sleep fragmentation/loss and obesity.
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Affiliation(s)
- Tathiana A Alvarenga
- Departamento de Psicobiologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil
| | - Guilherme L Fernandes
- Departamento de Psicobiologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil
| | - Lia R Bittencourt
- Departamento de Psicobiologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil
| | - Sergio Tufik
- Departamento de Psicobiologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil
| | - Monica Levy Andersen
- Departamento de Psicobiologia, Universidade Federal de São Paulo - UNIFESP, São Paulo, Brazil
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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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Berryman CE, McClung HL, Sepowitz JJ, Gaffney‐Stomberg E, Ferrando AA, McClung JP, Pasiakos SM. Testosterone status following short-term, severe energy deficit is associated with fat-free mass loss in U.S. Marines. Physiol Rep 2022; 10:e15461. [PMID: 36117330 PMCID: PMC9483439 DOI: 10.14814/phy2.15461] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 08/19/2022] [Accepted: 08/23/2022] [Indexed: 06/15/2023] Open
Abstract
The objective of this study was to determine metabolic and physiological differences between males with low testosterone (LT) versus those with normal testosterone (NT) following a period of severe energy deficit. In this secondary analysis, 68 male US Marines (mean ± SD, 24.6 ± 2.4 y) were dichotomized by testosterone concentration (< or ≥ 10.5 nmol/L as determined from a single blood sample collected between 0600-0630 after an 8-10 h overnight fast by automated immunoassay) following 7 days of near complete starvation (~300 kcal consumed/d, ~85% energy deficit) during Survival, Evasion, Resistance, and Escape (SERE) training. Dietary intake was assessed before (PRE) SERE. Body composition (dual-energy x-ray absorptiometry and peripheral quantitative computed tomography) and whole-body protein turnover (15 N alanine) were assessed before (PRE) and after (POST) SERE. Mean testosterone concentrations decreased PRE (17.5 ± 4.7 nmol/L) to POST (9.8 ± 4.0 nmol/L, p < 0.0001). When volunteers were dichotomized by POST testosterone concentrations [NT (n = 24) 14.1 ± 3.4 vs. LT (n = 44): 7.5 ± 1.8 nmol/L, p < 0.0001], PRE BMI, total fat mass, trunk fat mass, and testosterone were greater and the diet quality score and total carbohydrate intake were lower in NT compared to LT (p ≤ 0.05). LT lost more fat-free mass and less fat mass, particularly in the trunk region, compared to NT following SERE (p-interaction≤0.044). Whole-body protein synthesis, net balance, and flux decreased and whole-body protein breakdown increased from PRE to POST in both groups (p-time ≤0.025). Following short-term, severe energy deficit, Marines who exhibited low testosterone had greater fat-free mass loss than those who maintained normal testosterone concentrations. Altering body composition and dietary strategies prior to physical training that elicits severe energy deficit may provide an opportunity to attenuate post-training decrements in testosterone and its associated effects (e.g., loss of lean mass, performance declines, fatigue).
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Affiliation(s)
- Claire E. Berryman
- Military Nutrition DivisionUS Army Research Institute of Environmental MedicineNatickMassachusettsUSA
- Oak Ridge Institute for Science and EducationBelcampMarylandUSA
- Department of Nutrition and Integrative PhysiologyFlorida State UniversityTallahasseeFloridaUSA
| | - Holly L. McClung
- Military Nutrition DivisionUS Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - John J. Sepowitz
- Military Nutrition DivisionUS Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Erin Gaffney‐Stomberg
- Military Performance DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Arny A. Ferrando
- Department of Geriatrics, The Center for Translational Research in Aging & LongevityDonald W. Reynolds Institute of Aging, University of Arkansas for Medical SciencesLittle RockArkansasUSA
| | - James P. McClung
- Military Nutrition DivisionUS Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Stefan M. Pasiakos
- Military Performance DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusettsUSA
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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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11
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Beckner ME, Main L, Tait JL, Martin BJ, Conkright WR, Nindl BC. Circulating biomarkers associated with performance and resilience during military operational stress. Eur J Sport Sci 2021; 22:72-86. [PMID: 34346851 DOI: 10.1080/17461391.2021.1962983] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Adaptation to military operational stress is a complex physiological response that calls upon the sympathetic nervous system (SNS), hypothalamic pituitary adrenal (HPA) axis and immune system, to create a delicate balance between anabolism and catabolism and meet the demands of an ever-changing environment. As such, resilience, the ability to withstand and overcome the negative impact of stress on military performance, is likely grounded in an appropriate biological adaptation to encountered stressors. Neuroendocrine [i.e. cortisol, epinephrine (EPI), norepinephrine (NE), neuropeptide-Y (NPY), and brain derived neurotropic factor (BDNF)], inflammatory [i.e. interleukin 6 (IL-6), IL-1β, IL-4, IL-10 and tumour necrosis factor (TNF)-α], as well as growth and anabolic [i.e. insulin-like growth factor-I (IGF-I), testosterone, and dehydroepiandrosterone (DHEA)] biomarkers independently and interactively function in stress adaptations that are associated with a soldier's physical and psychological performance. In this narrative review, we detail biomarkers across neuroendocrine, inflammatory, and growth stimulating domains to better elucidate the biological basis of a resilient soldier. The findings from the reviewed studies indicate that military readiness and resiliency may be enhanced through better homeostatic control, better regulated inflammatory responses, and balanced anabolic/catabolic processes. It is unlikely that one class of biomarkers is better for assessing physiological resilience. Therefore, a biomarker panel that can account for appropriate balance across these domains may be superior in developing monitoring frameworks. Real-time physiological monitoring to assess biomarkers associated with resilience will be possible pending more sophisticated technologies and provide a field-expedient application for early identification and intervention of at-risk soldiers to improve military resiliency.
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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, USA
| | - Luana Main
- Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University, Geelong, Australia
| | - Jamie L Tait
- School of Exercise and Nutrition Sciences, Deakin University, Geelong, Australia
| | - Brian J Martin
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center. Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, PA, USA
| | - William R Conkright
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center. Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, PA, USA
| | - Bradley C Nindl
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center. Department of Sports Medicine and Nutrition, University of Pittsburgh, Pittsburgh, PA, USA
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12
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Vaara JP, Groeller H, Drain J, Kyröläinen H, Pihlainen K, Ojanen T, Connaboy C, Santtila M, Agostinelli P, Nindl BC. Physical training considerations for optimizing performance in essential military tasks. Eur J Sport Sci 2021; 22:43-57. [PMID: 34006204 DOI: 10.1080/17461391.2021.1930193] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Physically demanding essential military tasks include load carriage, manual material handling and casualty evacuation. This narrative review characterizes the main physical attributes related to performance of these occupational tasks and reviews physical training intervention studies in military settings to improve performance in these military tasks. Load carriage performance requires both aerobic and neuromuscular fitness with greater emphasis on maximal strength and absolute maximal oxygen uptake, especially when carrying heavier loads. In manual material handling, maximal strength and power are strongly associated with discrete lifting, while muscular strength, muscular endurance and aerobic fitness are also associated with repetitive lifting performance. Maximal strength including grip strength, muscular endurance, absolute maximal oxygen uptake and anaerobic capacity are associated with casualty evacuation performance. The results of the present review particularly emphasize the role of muscular fitness in successful performance of the reviewed military occupational tasks. Training intervention studies indicate that load carriage performance can be effectively improved by combining strength, aerobic and specific load carriage training. Improvement in maximal lifting capacity can be achieved by strength training or combined strength and aerobic training, while strength and aerobic training alone, or their combination are effective in improving repetitive lifting, and carry tasks. Only a few studies are available for casualty evacuation and the results are inconclusive but may indicate benefits of strength or combined training. Moreover, emphasis on lower volume but higher intensity in combined training may be a feasible and effective mode to improve military occupational performance in recruits and active-duty soldiers.
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Affiliation(s)
- Jani P Vaara
- National Defence University, Department of Leadership and Military Pedagogy, Helsinki, Finland
| | - Herbert Groeller
- Centre for Medical and Exercise Physiology, School of Medicine, University of Wollongong, Wollongong, Australia
| | - Jace Drain
- Defence Science and Technology Group, Fishermans Bends, Australia
| | - Heikki Kyröläinen
- National Defence University, Department of Leadership and Military Pedagogy, Helsinki, Finland.,Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland
| | - Kai Pihlainen
- Defence Command, Training Division, Finnish Defence Forces, Helsinki, Finland
| | - Tommi Ojanen
- Finnish Defence Research Agency, Human Performance Division, Finnish Defence Forces, Tuusula, Finland
| | - Chris Connaboy
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, USA
| | - Matti Santtila
- National Defence University, Department of Leadership and Military Pedagogy, Helsinki, Finland
| | - Philip Agostinelli
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, USA
| | - Brad C Nindl
- Neuromuscular Research Laboratory/Warrior Human Performance Research Center, University of Pittsburgh, Pittsburgh, PA, USA
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13
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Sharma A, Muresanu DF, Sahib S, Tian ZR, Castellani RJ, Nozari A, Lafuente JV, Buzoianu AD, Bryukhovetskiy I, Manzhulo I, Patnaik R, Wiklund L, Sharma HS. Concussive head injury exacerbates neuropathology of sleep deprivation: Superior neuroprotection by co-administration of TiO 2-nanowired cerebrolysin, alpha-melanocyte-stimulating hormone, and mesenchymal stem cells. PROGRESS IN BRAIN RESEARCH 2020; 258:1-77. [PMID: 33223033 DOI: 10.1016/bs.pbr.2020.09.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Sleep deprivation (SD) is common in military personnel engaged in combat operations leading to brain dysfunction. Military personnel during acute or chronic SD often prone to traumatic brain injury (TBI) indicating the possibility of further exacerbating brain pathology. Several lines of evidence suggest that in both TBI and SD alpha-melanocyte-stimulating hormone (α-MSH) and brain-derived neurotrophic factor (BDNF) levels decreases in plasma and brain. Thus, a possibility exists that exogenous supplement of α-MSH and/or BDNF induces neuroprotection in SD compounded with TBI. In addition, mesenchymal stem cells (MSCs) are very portent in inducing neuroprotection in TBI. We examined the effects of concussive head injury (CHI) in SD on brain pathology. Furthermore, possible neuroprotective effects of α-MSH, MSCs and neurotrophic factors treatment were explored in a rat model of SD and CHI. Rats subjected to 48h SD with CHI exhibited higher leakage of BBB to Evans blue and radioiodine compared to identical SD or CHI alone. Brain pathology was also exacerbated in SD with CHI group as compared to SD or CHI alone together with a significant reduction in α-MSH and BDNF levels in plasma and brain and enhanced level of tumor necrosis factor-alpha (TNF-α). Exogenous administration of α-MSH (250μg/kg) together with MSCs (1×106) and cerebrolysin (a balanced composition of several neurotrophic factors and active peptide fragments) (5mL/kg) significantly induced neuroprotection in SD with CHI. Interestingly, TiO2 nanowired delivery of α-MSH (100μg), MSCs, and cerebrolysin (2.5mL/kg) induced enhanced neuroprotection with higher levels of α-MSH and BDNF and decreased the TNF-α in SD with CHI. These observations are the first to show that TiO2 nanowired administration of α-MSH, MSCs and cerebrolysin induces superior neuroprotection following SD in CHI, not reported earlier. The clinical significance of our findings in light of the current literature is discussed.
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Affiliation(s)
- Aruna Sharma
- International Experimental Central Nervous System Injury & Repair (IECNSIR), Department of Surgical Sciences, Anesthesiology & Intensive Care Medicine, Uppsala University Hospital, Uppsala University, Uppsala, Sweden.
| | - Dafin F Muresanu
- Department of Clinical Neurosciences, University of Medicine & Pharmacy, Cluj-Napoca, Romania; "RoNeuro" Institute for Neurological Research and Diagnostic, Cluj-Napoca, Romania
| | - Seaab Sahib
- Department of Chemistry & Biochemistry, University of Arkansas, Fayetteville, AR, United States
| | - Z Ryan Tian
- Department of Chemistry & Biochemistry, University of Arkansas, Fayetteville, AR, United States
| | - Rudy J Castellani
- Department of Pathology, University of Maryland, Baltimore, MD, United States
| | - Ala Nozari
- Anesthesiology & Intensive Care, Massachusetts General Hospital, Boston, MA, United States
| | - José Vicente Lafuente
- LaNCE, Department of Neuroscience, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain
| | - Anca D Buzoianu
- Department of Clinical Pharmacology and Toxicology, "Iuliu Hatieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Igor Bryukhovetskiy
- Department of Fundamental Medicine, School of Biomedicine, Far Eastern Federal University, Vladivostok, Russia; Laboratory of Pharmacology, National Scientific Center of Marine Biology, Far East Branch of the Russian Academy of Sciences, Vladivostok, Russia
| | - Igor Manzhulo
- Department of Fundamental Medicine, School of Biomedicine, Far Eastern Federal University, Vladivostok, Russia; Laboratory of Pharmacology, National Scientific Center of Marine Biology, Far East Branch of the Russian Academy of Sciences, Vladivostok, Russia
| | - Ranjana Patnaik
- Department of Biomaterials, School of Biomedical Engineering, Indian Institute of Technology, Banaras Hindu University, Varanasi, India
| | - Lars Wiklund
- International Experimental Central Nervous System Injury & Repair (IECNSIR), Department of Surgical Sciences, Anesthesiology & Intensive Care Medicine, Uppsala University Hospital, Uppsala University, Uppsala, Sweden
| | - Hari Shanker Sharma
- International Experimental Central Nervous System Injury & Repair (IECNSIR), Department of Surgical Sciences, Anesthesiology & Intensive Care Medicine, Uppsala University Hospital, Uppsala University, Uppsala, Sweden.
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14
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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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15
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Ojanen T, Kyröläinen H, Kozharskaya E, Häkkinen K. Changes in strength and power performance and serum hormone concentrations during 12 weeks of task-specific or strength training in conscripts. Physiol Rep 2020; 8:e14422. [PMID: 32378340 PMCID: PMC7202986 DOI: 10.14814/phy2.14422] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 03/19/2020] [Accepted: 03/23/2020] [Indexed: 11/24/2022] Open
Abstract
The purpose of this study was to investigate the effects of two different training programs on strength and power performance and serum hormone concentrations. A total of 104 male soldiers volunteered and took part in the 12-week training period with baseline, mid-, and post-measurements of body composition, muscle strength, lower and upper body power, and blood samples to determine serum hormone concentrations. The mean (±SD) age of subjects was 20 ± 1 years, height 180 ± 6 cm and body mass 72.4 ± 8.8 kg. The subjects were divided into three different training groups: soldier task-specific training (TS), strength training (ST), and control (CON). Each group had a total of 18 training sessions during the 12-week study. In the muscle strength tests, most improvements could be observed in the TS and ST groups, especially, during the first weeks of the training period. Maximal isometric leg extension force increased significantly by 7.9 ± 12.2% (p < .05) in the TS and 7.1 ± 12.6% (p < .05) in the ST groups between the PRE and MID, as well as between the PRE and POST measurements by 8.1 ± 12.4% (p < .05) in TS and 12.3 ± 15.3% (p < .01) in ST. Serum TES concentration increased significantly in TS between the PRE and MID (16.8 ± 33.9%) and PRE and POST (11.2 ± 16.7%) measurements. Serum COR concentrations decreased in TS between the MID and POST (-7.8 ± 10.9%) and PRE and POST (-11.0 ± 14.3%) measurements. Although the differences observed were rather minor in magnitude, training in the TS and ST groups led to greater improvements in muscle strength and power performance compared to the training in the CON group. The development of strength and/or power of the lower and upper body was greater in the TS and ST groups, which is crucial for warfighter's performance. Therefore, it is important to have a structured resistance-training program during military training to optimize the strength, power, and military-specific performance.
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Affiliation(s)
- Tommi Ojanen
- Finnish Defence Research AgencyFinnish Defence ForcesJärvenpääFinland
| | - Heikki Kyröläinen
- Biology of Physical ActivityUniversity of JyväskyläJyväskyläFinland
- National Defence UniversityHelsinkiFinland
| | | | - Keijo Häkkinen
- Biology of Physical ActivityUniversity of JyväskyläJyväskyläFinland
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16
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Jensen AE, Arrington LJ, Turcotte LP, Kelly KR. Hormonal balance and nutritional intake in elite tactical athletes. Steroids 2019; 152:108504. [PMID: 31586604 DOI: 10.1016/j.steroids.2019.108504] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 08/14/2019] [Accepted: 09/24/2019] [Indexed: 10/25/2022]
Abstract
Chronic exposure to multifactorial stress, such as that endured by elite military operators, may lead to overtraining syndrome and negatively impact hormonal regulation. In acute settings (<6 mos), military training has been shown to lead to hormonal dysfunction; however, less is known about the consequences of long-term military training. Thus, the purpose of this study was to determine the chronic effects of military operations and training on the hormone profile of elite military operators. A cross-sectional, random sample of active duty elite US military operators (n = 65, age = 29.8 ± 1.0 yrs, height = 178.4 ± 0.7 cm, weight = 85.1 ± 2.0 kg) concomitantly engaged in rigorous physical training were recruited to participate in the study. Following an overnight fast, waking plasma concentrations of luteinizing hormone, total testosterone (TT), free testosterone, sex-hormone binding globulin, cortisol, thyroid stimulating hormone, triiodothyronine, and thyroxine were obtained. Data were analyzed for correlations and compared against normative reference values. There was a significant positive correlation between TT and cortisol (R2 = 0.07; P = 0.038). In addition, 43% of the participants (n = 28) had TT below age-based normative reference ranges. These results indicate that long-term military operations and training may place a large burden on the operators and depress or alter the hypothalamic pituitary, adrenal, gonadal, and thyroid axes.
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Affiliation(s)
- Andrew E Jensen
- Naval Health Research Center, Warfighter Performance Department, 140 Sylvester Road, San Diego, CA 92106, United States; Leidos Inc., 10260 Campus Point Drive, San Diego, CA 92121, United States; University of Southern California, Biological Sciences, Human and Evolutionary Biology, Dornsife College of Letters, Arts and Sciences, 3616 Trousdale Parkway, AHF 247, Los Angeles, CA 90089, United States
| | - Laura J Arrington
- Naval Health Research Center, Warfighter Performance Department, 140 Sylvester Road, San Diego, CA 92106, United States; Leidos Inc., 10260 Campus Point Drive, San Diego, CA 92121, United States
| | - Lorraine P Turcotte
- University of Southern California, Biological Sciences, Human and Evolutionary Biology, Dornsife College of Letters, Arts and Sciences, 3616 Trousdale Parkway, AHF 247, Los Angeles, CA 90089, United States
| | - Karen R Kelly
- Naval Health Research Center, Warfighter Performance Department, 140 Sylvester Road, San Diego, CA 92106, United States; University of Southern California, Biological Sciences, Human and Evolutionary Biology, Dornsife College of Letters, Arts and Sciences, 3616 Trousdale Parkway, AHF 247, Los Angeles, CA 90089, United States.
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17
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Salonen M, Huovinen J, Kyröläinen H, Piirainen JM, Vaara JP. Neuromuscular Performance and Hormonal Profile During Military Training and Subsequent Recovery Period. Mil Med 2018; 184:e113-e119. [DOI: 10.1093/milmed/usy176] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 06/15/2018] [Indexed: 11/14/2022] Open
Affiliation(s)
- Mika Salonen
- Department of Leadership and Military Pedagogy, National Defense University, Santahamina, Helsinki, Finland
| | - Jukka Huovinen
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Rautpohjankatu 8, Jyväskylä, Finland
| | - Heikki Kyröläinen
- Department of Leadership and Military Pedagogy, National Defense University, Santahamina, Helsinki, Finland
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Rautpohjankatu 8, Jyväskylä, Finland
| | - Jarmo M Piirainen
- Neuromuscular Research Center, Faculty of Sport and Health Sciences, University of Jyväskylä, Rautpohjankatu 8, Jyväskylä, Finland
| | - Jani P Vaara
- Department of Leadership and Military Pedagogy, National Defense University, Santahamina, Helsinki, Finland
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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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Caloric Restriction Effect on Proinflammatory Cytokines, Growth Hormone, and Steroid Hormone Concentrations during Exercise in Judokas. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2015; 2015:809492. [PMID: 26075039 PMCID: PMC4446567 DOI: 10.1155/2015/809492] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Revised: 02/28/2015] [Accepted: 03/02/2015] [Indexed: 11/30/2022]
Abstract
The aim of this study was to evaluate the effect of caloric restriction on the immune and hormonal responses during exercise in judo athletes. In a randomised order, 11 male judokas (age: 20.45 ± 0.51; height: 1.71 ± 0.3 m; and body weight: 75.9 ± 3.1 kg) participate in this study during a period of weight maintenance (baseline) and after 7 days of caloric restriction (CR). All subjects performed the Special Judo Fitness Test (SJFT) during the two conditions. Values for nutrient intakes were obtained from a 7 d food record kept during a period of weight maintenance and after a 7-day food restriction (−5~6 MJ/day). Our results showed that CR resulted in significant decreases in body weight (P < 0.05) and performance (P < 0.05). However, heart rate and SJFT index (P < 0.05) increase significantly during CR in comparison to baseline. Moreover, exercise leads to a significant increase in testosterone, cortisol, growth hormone (GH), leukocytes, neutrophils, TNF-α, and IL-6, in both CR and baseline conditions. Compared to baseline, TNF-α and IL-6 were significantly higher during CR condition (P < 0.05). Additionally, CR leads to an increase in cortisol and GH (P < 0.05) and a decrease in testosterone concentrations (P < 0.05).
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20
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Pasiakos SM, Margolis LM, Orr JS. Optimized dietary strategies to protect skeletal muscle mass during periods of unavoidable energy deficit. FASEB J 2014; 29:1136-42. [DOI: 10.1096/fj.14-266890] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 12/01/2014] [Indexed: 12/14/2022]
Affiliation(s)
- Stefan M. Pasiakos
- Military Nutrition DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Lee M. Margolis
- Military Nutrition DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusettsUSA
| | - Jeb S. Orr
- Military Nutrition DivisionU.S. Army Research Institute of Environmental MedicineNatickMassachusettsUSA
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21
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Boin AC, Nozoe KT, Polesel DN, Andersen ML, Tufik S. The potential role of sleep in sexual dysfunction in patients with schizophrenia. Schizophr Res 2014; 154:126-7. [PMID: 24556470 DOI: 10.1016/j.schres.2014.01.042] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 01/28/2014] [Accepted: 01/28/2014] [Indexed: 10/25/2022]
Affiliation(s)
- Andre Campiolo Boin
- Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, SP, Brazil; Marília Medical School, Marília, SP, Brazil
| | - Karen Tieme Nozoe
- Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, SP, Brazil
| | | | - Monica Levy Andersen
- Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, SP, Brazil.
| | - Sergio Tufik
- Departamento de Psicobiologia, Universidade Federal de São Paulo, São Paulo, SP, Brazil
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22
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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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Qiu C, Frederick IO, Sorensen TK, Enquobahrie DA, Williams MA. Sleep duration and plasma leptin concentrations in early pregnancy among lean and overweight/obese women: a cross sectional study. BMC Res Notes 2014; 7:20. [PMID: 24405869 PMCID: PMC3896691 DOI: 10.1186/1756-0500-7-20] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 01/03/2014] [Indexed: 12/27/2022] Open
Abstract
Background Early-pregnancy short sleep duration is predictive of gestational diabetes and preeclampsia; mechanisms for these associations are unknown. Leptin, an adipocyte-derived peptide involved in regulating food intake and energy expenditure, may play a role in these observed associations. Given inconsistent reports linking short sleep duration with leptin, and absence of studies among pregnant women, we examined the association of maternal sleep duration with plasma leptin in early pregnancy. Methods This cross-sectional study included 830 pregnant women. Plasma leptin was measured in samples collected around 13 weeks gestation. Sleep duration was categorized as: ≤5, 6, 7–8 (reference), and ≥9 hours. Differences in leptin concentrations across categories were estimated using linear regression. Analyses were completed for lean and overweight/obese women. Results Overall, women with long sleep duration had elevated plasma leptin (p-value = 0.04). However, leptin concentrations were not statistically significantly elevated in women with a short sleep duration. There was no association of leptin with sleep duration among lean women. Among overweight/obese women, a U-shaped relation between leptin and sleep duration was observed: Mean leptin was elevated (β = 21.96 ng/ml, P < 0.001) among women reporting ≤5 hour of sleep compared with reference group; and women reporting ≥9 hours of sleep also had elevated leptin (β = 4.29 ng/ml, P = 0.09). Conclusions Short sleep duration, and to a lesser extent long sleep duration, were associated with elevated leptin among overweight/obese women. These data add some evidence to help understand mechanistic relationships of sleep duration with pregnancy complications.
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Affiliation(s)
- Chunfang Qiu
- Center for Perinatal Studies, Swedish Medical Center, 1124 Columbia Street, Suite 750, Seattle, WA 98104, USA.
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Abstract
IGF-I (insulin-like growth factor-I) is a peptide hormone, produced predominantly by the liver in response to pituitary GH (growth hormone), which is involved in a wide variety of physiological processes. It acts in an endocrine, paracrine and autocrine manner to promote growth. The production of IGF-I signals the availability of nutrients needed for its anabolic actions. Recently, there has been growing interest in its role in health and disease. IGF-I has long been known to be regulated by nutrition and dysregulated in states of under- and over-nutrition, its serum concentrations falling in malnutrition and responding promptly to refeeding. This has led to interest in its utility as a nutritional biomarker. A considerable evidence base supports utility for measurement of IGF-I in nutritional contexts. Its concentration may be valuable in providing information on nutritional status, prognosis and in monitoring nutritional support. However, it is insufficiently specific for use as a screening test for under nutrition as its serum concentration is influenced by many factors other than nutritional status, notably the APR (acute-phase response) and endocrine conditions. Concentrations should be interpreted along with clinical findings and the results of other investigations such as CRP (C-reactive protein). More recently, there has been interest in free IGF-I which holds promise as a nutritional marker. The present review covers nutritional regulation of IGF-I and its dysregulation in disease, then goes on to review recent studies supporting its utility as a nutritional marker in clinical contexts. Although not currently recommended by clinical guidelines, it is likely that, in time, measurement of IGF-I will become a routine part of nutritional assessment in a number of these contexts.
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Abedelmalek S, Souissi N, Chtourou H, Denguezli M, Aouichaoui C, Ajina M, Aloui A, Dogui M, Haddouk S, Tabka Z. Effects of partial sleep deprivation on proinflammatory cytokines, growth hormone, and steroid hormone concentrations during repeated brief sprint interval exercise. Chronobiol Int 2013; 30:502-9. [PMID: 23281720 DOI: 10.3109/07420528.2012.742102] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The purpose of this study was to evaluate the effects of partial sleep deprivation (PSD) on circulating concentrations of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in relation to the secretory profiles of growth hormone (GH), cortisol, and testosterone during a repeated brief sprint interval exercise. Thirty healthy football players (mean age: 21.1 [range: 18-24] years; body mass index [BMI]: 22.6 [range: 18.47-24.46] Kg/m(2)) completed two test sessions at 08:00 h, one scheduled after a baseline night (bedtime: from 22:30 to 07:00 h) and the other after a PSD night caused by an early awakening (bedtime: from 22:30 to 03:00 h). During each session, participants performed 4 × 250-m run on a treadmill at a constant intensity of 80% of the personal maximal speed with a 3-min recovery in between. Tests session were performed at 08:00 h. Blood samples were collected before, immediately after the first and the fourth 250-m run, and 60 min after the exercise. The results showed that cortisol concentrations were not affected by the PSD. However, GH and testosterone concentrations were higher (p < .05) 60 min after the exercise during PSD in comparison with baseline. Likewise, plasma concentrations of IL-6 and TNF-α were higher (p < .05) after PSD during the exercise (i.e., the first and the fourth run) and remained elevated during the recovery period (i.e., 60 min after the exercise). In conclusion, these results showed that sleep restriction increases the proinflammatory cytokine, GH, and testosterone concentrations after physical exercise but did not affect the cortisol responses.
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Affiliation(s)
- Salma Abedelmalek
- Department of Physiology, Sousse Faculty of Medicine, Sousse, Tunisia
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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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Huovinen J, Kyrolainen H, Linnamo V, Tanskanen M, Kinnunen H, Hakkinen K, Tulppo M. Cardiac autonomic function reveals adaptation to military training. Eur J Sport Sci 2011. [DOI: 10.1080/17461391.2010.506659] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Aldabal L, Bahammam AS. Metabolic, endocrine, and immune consequences of sleep deprivation. Open Respir Med J 2011; 5:31-43. [PMID: 21754974 PMCID: PMC3132857 DOI: 10.2174/1874306401105010031] [Citation(s) in RCA: 187] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Revised: 04/18/2011] [Accepted: 05/02/2011] [Indexed: 12/29/2022] Open
Abstract
Over the last three to four decades, it has been observed that the average total hours of sleep have decreased to less than seven hours per person per night. Concomitantly, global figures relating to obesity and diabetes mellitus have increased in an alarming fashion in adults and children, and it has been hypothesized that neuro-hormonal changes accompanying this behavioral sleep deprivation may lead to insulin resistance and, subsequently, to diabetes mellitus. Sleep deprivation has been associated with multiple physiological changes, including increased cortisol and ghrelin levels, decreased leptin levels and impaired glucose metabolism. Experimental studies have also shown an increase in inflammatory and pro-inflammatory markers, which are indicators of body stress, under sleep deprivation. This review elaborates further on this hypothesis, exploring the molecular basis for the link between both entities and the underlying pathophysiology that results in insulin resistance and diabetes mellitus. We review the results of experimental and epidemiological studies, specifically examining the relationship between sleep duration and the immune and endocrine systems.
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Affiliation(s)
- Laila Aldabal
- Department of Pulmonary Medicine, Rashid Hospital, Dubai Health Authority, United Arab Emirates
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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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Simpson NS, Banks S, Dinges DF. Sleep restriction is associated with increased morning plasma leptin concentrations, especially in women. Biol Res Nurs 2010; 12:47-53. [PMID: 20453022 DOI: 10.1177/1099800410366301] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
STUDY OBJECTIVES We evaluated the effects of sleep restriction on leptin levels in a large, diverse sample of healthy participants, while allowing free access to food. METHODS Prospective experimental design. After 2 nights of baseline sleep, 136 participants (49% women, 56% African Americans) received 5 consecutive nights of 4 hours time in bed (TIB). Additionally, one subset of participants received 2 additional nights of either further sleep restriction (n = 27) or increased sleep opportunity (n = 37). Control participants (n = 9) received 10 hr TIB on all study nights. Plasma leptin was measured between 10:30 a.m. and 12:00 noon following baseline sleep, after the initial sleep-restriction period, and after 2 nights of further sleep restriction or recovery sleep. RESULTS Leptin levels increased significantly among sleep-restricted participants after 5 nights of 4 hr TIB (Z = -8.43, p < .001). Increases were significantly greater among women compared to men (Z = -4.77, p < .001) and among participants with higher body mass index (BMI) compared to those with lower (Z = -2.09, p = .036), though participants in all categories (sex, race/ethnicity, BMI, and age) demonstrated significant increases. There was also a significant effect of allowed TIB on leptin levels following the 2 additional nights of sleep restriction (p < .001). Participants in the control condition showed no significant changes in leptin levels. CONCLUSIONS These findings suggest that sleep restriction with ad libitum access to food significantly increases morning plasma leptin levels, particularly among women.
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Affiliation(s)
- Norah S Simpson
- Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
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Tyyskä J, Kokko J, Salonen M, Koivu M, Kyröläinen H. Association with physical fitness, serum hormones and sleep during a 15-day military field training. J Sci Med Sport 2010; 13:356-9. [PMID: 19574096 DOI: 10.1016/j.jsams.2009.04.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2008] [Revised: 04/07/2009] [Accepted: 04/08/2009] [Indexed: 10/20/2022]
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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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Karl JP, Alemany JA, Koenig C, Kraemer WJ, Frystyk J, Flyvbjerg A, Young AJ, Nindl BC. Diet, body composition, and physical fitness influences on IGF-I bioactivity in women. Growth Horm IGF Res 2009; 19:491-496. [PMID: 19467892 DOI: 10.1016/j.ghir.2009.04.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2009] [Revised: 04/16/2009] [Accepted: 04/22/2009] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Insulin-like growth factor I (IGF-I) is a metabolic-regulatory hormone that mediates a variety of physiologic functions. Body composition, fitness status and intake of certain micro- and macronutrients are associated with circulating concentrations of immunoreactive IGF-I. The influence of these factors on IGF-I bioactivity; however, is undetermined. We assessed the relationships between IGF-I bioactivity and lifestyle factors purportedly associated with IGF-I immunoreactivity. DESIGN In a cross sectional study, fasted blood samples were obtained from 44 lightly active, college-age (20+/-2 yrs) women. IGF-I bioactivity was estimated by an assay which determines the ability of serum IGFs to phosphorylate IGF-I receptors in cultured cells; free and total IGF-I were measured by immunoassay. Estradiol and progesterone were measured by immunoassay. Body mass index was calculated from measured height and weight, bone mineral density and body fat percentage measured by dual energy X-ray absorptiometry, and peak oxygen consumption (VO(2peak)) determined during a graded treadmill protocol. A food frequency questionnaire measured habitual and a 5-day food record assessed short-term micro- and macronutrient intakes. Associations between bioactive, free and total IGF-I with body composition, sex hormones, VO(2peak), and dietary intake were assessed using univariate and multiple linear regression analyses. RESULTS Associations between bioactive IGF-I with age (r=-0.36, P<0.05), body fat percentage (r=-0.32, P<0.05), estradiol (r=0.31, P<0.05) and progesterone (r=0.33, P<0.05) concentrations, habitual alcohol (r=-0.38, P<0.05) and selenium intakes (r=0.41, P<0.01), free IGF-I with age (r=-0.34, P<0.05), estradiol (r=0.48, P<0.01) and progesterone (r=0.52, P<0.001) concentrations, habitual alcohol (r=-0.33, P<0.05) and isoflavone intakes (r=0.30, P<0.05) and total IGF-I with age (r=-0.27, P<0.05) and habitual alcohol intake (r=-0.33, P<0.05) were observed. Habitual alcohol intake was a negative predictor of bioactive, free and total IGF-I in multivariate models. CONCLUSION Of the lifestyle factors measured, the most robust relationship observed was a negative association between habitual alcohol intake and all measures of IGF-I. This finding suggests that alcohol intake may blunt the physiologic actions of the IGF-I axis.
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Affiliation(s)
- J Philip Karl
- US Army Research Institute of Environmental Medicine, 42 Kansas St., Natick, MA 01760, USA
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Huovinen J, Tulppo M, Nissilä J, Linnamo V, Häkkinen K, Kyrolainen H. Relationship between heart rate variability and the serum testosterone-to-cortisol ratio during military service. Eur J Sport Sci 2009. [DOI: 10.1080/17461390902874040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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de Graaf-Roelfsema E, Veldhuis PP, Keizer HA, van Ginneken MME, van Dam KG, Johnson ML, Barneveld A, Menheere PPCA, van Breda E, Wijnberg ID, van der Kolk JH. Overtrained horses alter their resting pulsatile growth hormone secretion. Am J Physiol Regul Integr Comp Physiol 2009; 297:R403-11. [PMID: 19494168 DOI: 10.1152/ajpregu.90778.2008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The influence of intensified and reduced training on nocturnal growth hormone (GH) secretion and elimination dynamics was studied in young (1.5 yr) Standardbred geldings to detect potential markers indicative for early overtraining. Ten horses trained on a treadmill for 32 wk in age-, breed-, and gender-matched fixed pairs. Training was divided into four phases (4, 18, 6, and 4 wk, respectively): 1) habituation to high-speed treadmill trotting, 2) normal training, in which speed and duration of training sessions were gradually increased, 3) in this phase, the horses were divided into 2 groups: control (C) and intensified trained (IT) group. In IT, training intensity, duration, and frequency were further increased, whereas in control these remained unaltered, and 4) reduced training (RT). At the end of phases 2, 3, and 4, blood was sampled overnight every 5 min for 8 h for assessment of GH secretory dynamics using pulse detection, deconvolution analysis, and approximate entropy (ApEn). Intensified training induced overtraining (performance decreased by 19% compared with C), which was associated with an increase in concentration peaks number (3.6 vs. 2.0, respectively), a smaller peak secretion pattern with a prolonged half-life (15.2 vs. 7.3 min, respectively), and an increased ApEn (0.89 vs. 0.49, respectively). RT did not lead to full recovery for the overtrained horses. The increased irregularity of nocturnal GH pulsatility pattern is indicative of a loss of coordinated control of GH regulation. Longer phases of somatostatin withdrawal are hypothesized to be the underlying mechanism for the observed changes in GH pulsatility pattern.
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Affiliation(s)
- E de Graaf-Roelfsema
- Dept. of Equine Sciences, Medicine Section, Faculty of Veterinary Medicine, Utrecht Univ., Yalelaan 114, 3584 CM Utrecht, The Netherlands.
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Andersen ML, Tufik S. The effects of testosterone on sleep and sleep-disordered breathing in men: Its bidirectional interaction with erectile function. Sleep Med Rev 2008; 12:365-79. [DOI: 10.1016/j.smrv.2007.12.003] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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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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Rasmussen MH, Wildschiødtz G, Juul A, Hilsted J. Polysomnographic sleep, growth hormone insulin-like growth factor-I axis, leptin, and weight loss. Obesity (Silver Spring) 2008; 16:1516-21. [PMID: 18464752 DOI: 10.1038/oby.2008.249] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Short sleep appears to be strongly associated with obesity and altered metabolic function, and sleep and growth hormone (GH) secretion seems interlinked. In obesity, both the GH-insulin-like-growth-factor-I (GH-IGF-I) axis and sleep have been reported to be abnormal, however, no studies have investigated sleep in relation to the GH-IGF-I axis and weight loss in obese subjects. In this study polygraphic sleep recordings, 24-h GH release, 24-h leptin levels, free-IGF-I, total-IGF-I, IGF-binding protein-3 (IGFBP-3), acid-labile subunit (ALS), cortisol and insulin sensitivity were determined in six severely obese subjects (BMI: 41+/-1 kg/m(2), 32+/-2 years of age), cross-sectional at baseline, and longitudinal after a dramatically diet-induced weight loss (36+/-7 kg). Ten age- and gender-matched nonobese subjects served as controls. Sleep duration (360+/-17 vs. 448+/-15 min/night; P<0.01), 24-h GH (55+/-9 vs. 344+/-55 mU/l.24 h; P<0.01), free-IGF-I (2.3+/-0.42 vs. 5.7+/-1.2 microg/l; P<0.01), and total-IGF-I (186+/-21 vs. 301+/-18 microg/l; P<0.01) were significantly decreased and 24-h leptin levels were increased (35+/-5 vs. 12+/-3 microg/l; P<0.01) in obese subjects at pre-weight loss compared with nonobese subjects After diet-induced weight loss the differences in GH, free IGF-I, and leptin were no longer present between previously obese and nonobese subjects, whereas a significant difference in sleep duration and total IGF-I levels persisted. Rapid eye movement (REM) sleep, non-REM sleep, IGFBP-3, ALS, and cortisol levels were similar in obese and nonobese subjects. Sleep duration, 24-h GH, and IGF-I levels were decreased and 24-h leptin levels were increased in obese subjects. We conclude that hyposomatotropism and hyperleptinemia in obesity are transient phenomena reversible with weight loss, whereas short sleep seems to persist after weight has been reduced dramatically.
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Affiliation(s)
- Michael H Rasmussen
- Department of Endocrinology, Hvidovre Hospital, University of Copenhagen, Hvidovre, Denmark.
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Berg U, Enqvist JK, Mattsson CM, Carlsson-Skwirut C, Sundberg CJ, Ekblom B, Bang P. Lack of sex differences in the IGF-IGFBP response to ultra endurance exercise. Scand J Med Sci Sports 2008; 18:706-14. [PMID: 18248538 DOI: 10.1111/j.1600-0838.2007.00758.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The insulin-like growth factor (IGF)-IGF binding proteins (BP) and the pituitary-gonadal axes were investigated during ultra endurance exercise in 16 endurance-trained athletes (seven women). Median duration of the race was 6.3 days. Although food and drink were ad libitum, energy balance was negative. Blood samples were drawn before (PRE), at the end of (END) and 24 h after (POST24h) the race. Serum concentrations of total IGF-I (t-IGF-I) and free IGF-I (f-IGF-I) decreased by 33 (SD 38)% and 54 (19)%, respectively. The decrease in t-IGF-I appeared to be associated to the total energy deficit during the race. At END, the IGFBP-3 fragmentation and IGFBP-1 were increased but these changes did not predict changes in f-IGF-I. An increase in POST24h IGFBP-2 levels in women was the only sex difference. Testosterone was decreased by 67 (12)% in the men and estradiol became undetectable in the women without any detectable increase in LH and/or FSH. In conclusion ultra endurance exercise results in similar IGF-IGFBP responses in men and women reflecting a catabolic state. IGFBP-2 was the only exception, with increased levels in women after exercise. A concomitant decrease in gonadal hormones was not related to endocrine changes in the IGF-IGFBP axis but may be related to local changes in IGF-I expression.
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Affiliation(s)
- U Berg
- Department of Woman and Child Health, Pediatric Endocrinology Unit, Karolinska Institutet, Astrid Lindgren Children's Hospital, Stockholm, Sweden.
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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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