Special Issue "Exercise Endocrinology"

A special issue of Endocrines (ISSN 2673-396X). This special issue belongs to the section "Exercise Endocrinology".

Deadline for manuscript submissions: closed (20 March 2021).

Special Issue Editor

Prof. Dr. Anthony C. Hackney
E-Mail Website
Guest Editor
Department of Exercise and Sport Science, Department of Nutrition, Gilling's School of Global Public Health, University of North Carolina, Chapel Hill, NC, United States
Interests: exercise endocrinology, hormones, stress, reproductive physiology

Special Issue Information

Dear Colleagues,

Physical activity and exercise are behavioral components that the major world health organizations have necessitated as essential for all individuals to incorporate into their lifestyle in order to be more healthy. As a result, increasing number of individuals are attempting to engage in regular exercise training. The physiological adaptations occurring in response to exercise training are well documented and come about due to the plasticity of the various tissues and organs of the human body. An enhanced capacity for energy metabolism, cardiovascular-hematological function, muscular strength-endurance and many other adaptations occur to facilitate improved exercise and physical work capacity following such training. An integral physiologic component in enabling and regulating this adaptation process are the hormones associated with the endocrine system. 

The study of Exercise Endocrinology began in the late 1960s, shortly after the development and advancement of the radioimmunoassay procedural technique which allowed for a more accurate assessment of hormonal substances in humans. Since that time forward there have been numerous exercise studies involving endocrinological measurements. However, with the advent of the 21st century and new technological breakthroughs in analytical procedures there has been renewed interest in hormones, and an ever more rapidly accelerating examination of the role hormones play in bringing about the adaptive response in humans. This heightened interest has led to exciting scientific findings on the impact, limits and functions of the endocrine system in exercising people, especially in women who have traditionally been an understudied population. 

This Special Issue of Endocrines welcomes original experimental and clinical studies on the hormone changes in response to acute exercise as well as in response to more chronic adaptations with training. Comprehensive reviews on select endocrine gland function in acute or chronic settings are welcome too. In particular work is encouraged which has examined exercising women, and/or female athlete endocrinology-physiology.

Prof. Dr. Anthony C. Hackney
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Endocrines is an international peer-reviewed open access quarterly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1000 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Hormones
  • Endocrines
  • Exercise
  • Stress
  • Energy expenditure
  • Sport
  • Athletes

Published Papers (7 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Editorial

Jump to: Research, Review

Editorial
Exercise Endocrinology: “What Comes Next?”
Endocrines 2021, 2(3), 167-170; https://0-doi-org.brum.beds.ac.uk/10.3390/endocrines2030017 - 29 Jun 2021
Cited by 1 | Viewed by 738
Abstract
Endocrinology is a branch of physiology medical science that many exercise scientists are embracing in their research pursuits, so much so that “exercise endocrinology” is now viewed by many as a viable subdiscipline in the field [...] Full article
(This article belongs to the Special Issue Exercise Endocrinology)

Research

Jump to: Editorial, Review

Article
Influence of Menstrual Cycle or Hormonal Contraceptive Phase on Energy Intake and Metabolic Hormones—A Pilot Study
Endocrines 2021, 2(2), 79-90; https://0-doi-org.brum.beds.ac.uk/10.3390/endocrines2020008 - 16 Apr 2021
Viewed by 1535
Abstract
Sex hormones are suggested to influence energy intake (EI) and metabolic hormones. This study investigated the influence of menstrual cycle (MC) and hormonal contraceptive (HC) cycle phases on EI, energy availability (EA), and metabolic hormones in recreational athletes (eumenorrheic, NHC = 15 and [...] Read more.
Sex hormones are suggested to influence energy intake (EI) and metabolic hormones. This study investigated the influence of menstrual cycle (MC) and hormonal contraceptive (HC) cycle phases on EI, energy availability (EA), and metabolic hormones in recreational athletes (eumenorrheic, NHC = 15 and monophasic HC-users, CHC = 9). In addition, 72-h dietary and training logs were collected in addition to blood samples, which were analyzed for 17β-estradiol (E2), progesterone (P4), leptin, total ghrelin, insulin, and tri-iodothyronine (T3). Measurements were completed at four time-points (phases): Bleeding, mid-follicular (FP)/active 1, ovulation (OVU)/active 2, mid-luteal (LP)/inactive in NHC/CHC, respectively. As expected, E2 and P4 fluctuated significantly in NHC (p < 0.05) and remained stable in CHC. In NHC, leptin increased significantly between bleeding and ovulation (p = 0.030) as well as between FP and OVU (p = 0.022). No group differences in other measured hormones were observed across the MC and HC cycle. The mean EI and EA were similar between phases, with no significant differences observed in macronutrient intake over either the MC or HC. While the MC phase might have a small, but statistically significant effect on leptin, the findings of the present study suggest that the MC or HC phase does not significantly alter ad libitum EI or EA in recreational athletes. Full article
(This article belongs to the Special Issue Exercise Endocrinology)
Show Figures

Figure 1

Article
The Effect of High-Intensity Exercise on Changes in Salivary and Serum Cortisol Proportion Dynamics
Endocrines 2021, 2(1), 44-53; https://0-doi-org.brum.beds.ac.uk/10.3390/endocrines2010005 - 23 Feb 2021
Viewed by 1002
Abstract
Typically, salivary cortisol is reported as 5–10% of total cortisol, but the stability of this proportion and the effect of exercise on the 24-h profile is unclear. Therefore, this study investigated the circadian rhythm of the proportion of serum cortisol represented by salivary [...] Read more.
Typically, salivary cortisol is reported as 5–10% of total cortisol, but the stability of this proportion and the effect of exercise on the 24-h profile is unclear. Therefore, this study investigated the circadian rhythm of the proportion of serum cortisol represented by salivary cortisol, and the impact of acute high-intensity exercise. Recreationally trained males (n = 8, age = 25.7 ± 2.4 years, height = 174.7 ± 7.8 cm, mass = 69.8 ± 12.1 kg) completed two 24-h profiles (rest and exercise conditions) for serum (Q60) and salivary (Q120) cortisol. Exercise consisted of 5 × 30 s sprinting intervals on the cycle ergometer. Cortisol was assessed using commercially available assays. The proportion (Cprop) of serum cortisol (Cser) represented by salivary cortisol (Csal) was calculated as [Cprop = Csal/ Cser × 100]. Multilevel growth models tested for trends across the 24-h profile. The highest relation between Cser and Csal was observed at 08:00 AM (r = 0.90). The average Cprop was 5.95% and demonstrated a circadian profile characterized by a cubic model. Acute exercise did not alter Cser, Csal, or Cprop. Thus, the proportion of Cser represented by Csal changes across a 24-h period and should be accounted for if using salivary cortisol to reflect circadian output of cortisol. Full article
(This article belongs to the Special Issue Exercise Endocrinology)
Show Figures

Figure 1

Review

Jump to: Editorial, Research

Review
Natural Killer Cell Mobilization in Breast and Prostate Cancer Survivors: The Implications of Altered Stress Hormones Following Acute Exercise
Endocrines 2021, 2(2), 121-132; https://0-doi-org.brum.beds.ac.uk/10.3390/endocrines2020012 - 19 May 2021
Viewed by 780
Abstract
Natural killer (NK) cells from the innate immune system are integral to overall immunity and also in managing the tumor burden during cancer. Breast (BCa) and prostate cancer (PCa) are the most common tumors in U.S. adults. Both BCa and PCa are frequently [...] Read more.
Natural killer (NK) cells from the innate immune system are integral to overall immunity and also in managing the tumor burden during cancer. Breast (BCa) and prostate cancer (PCa) are the most common tumors in U.S. adults. Both BCa and PCa are frequently treated with hormone suppression therapies that are associated with numerous adverse effects including direct effects on the immune system. Regular exercise is recommended for cancer survivors to reduce side effects and improve quality of life. Acute exercise is a potent stimulus for NK cells in healthy individuals with current evidence indicating that NK mobilization in individuals with BCa and PCa is comparable. NK cell mobilization results from elevations in shear stress and catecholamine levels. Despite a normal NK cell response to exercise, increases in epinephrine are attenuated in BCa and PCa. The significance of this potential discrepancy still needs to be determined. However, alterations in adrenal hormone signaling are hypothesized to be due to chronic stress during cancer treatment. Additional compensatory factors induced by exercise are reviewed along with recommendations on standardized approaches to be used in exercise immunology studies involving oncology populations. Full article
(This article belongs to the Special Issue Exercise Endocrinology)
Show Figures

Figure 1

Review
Testosterone Boosters Intake in Athletes: Current Evidence and Further Directions
Endocrines 2021, 2(2), 109-120; https://0-doi-org.brum.beds.ac.uk/10.3390/endocrines2020011 - 17 May 2021
Viewed by 1267
Abstract
“Testosterone boosters” (TB)—are supplements that are claimed to increase testosterone levels in the human body. While the consumption of TB may be popular among athletes, there is insufficient evidence both about the safety and the real efficacy of TB. In our review, we [...] Read more.
“Testosterone boosters” (TB)—are supplements that are claimed to increase testosterone levels in the human body. While the consumption of TB may be popular among athletes, there is insufficient evidence both about the safety and the real efficacy of TB. In our review, we searched MEDLINE/PubMed and Cochrane Library for studies on the effects of 15 substances that are claimed to increase testosterone levels Anacyclus pyrethrum; Bulbine natalensis; Epimedium (horny goat weed); L-arginine; L-carnitine; magnesium; Mucuna pruriens; pantothenic acid; selenium; shilajit Eurycoma longifolia (Tongkat Ali); Serenoa repens (saw palmetto); boron; Withania somnifera (ashwagandha); and Trigonella foenum-graecum (fenugreek) in athletes and healthy adults under 55 years of age. We found such studies regarding 10 out of 15 substances: L-arginine (3 studies); L-carnitine (2); magnesium (1); selenium (2); shilajit (1); Tongkat Ali (2); Serenoa repens (1); boron (3); ashwagandha root (2); and fenugreek (7). Many of them fail to prove the efficacy of these substances to increase testosterone levels. Tongkat Ali, ashwagandha, and fenugreek were the substances with the strongest evidence. The positive effect of magnesium and shilajit on testosterone concentration was shown in single studies. Conflicting data found that L-arginine, L-carnitine, Serenoa repens, selenium and boron do not appear to increase testosterone levels. There are almost no data on the safety profile of various TB components; however, certain TB components may be linked to coagulation, and pancreatic and hepatic disorders. Based on the review, the authors conclude that at present TB cannot be recommended for use by athletes due to insufficient data on their efficacy and safety. Full article
(This article belongs to the Special Issue Exercise Endocrinology)
Show Figures

Figure 1

Review
Endocrine Responses to Sport-Related Brain Injury in Female Athletes: A Narrative Review and a Call for Action
Endocrines 2021, 2(2), 99-108; https://0-doi-org.brum.beds.ac.uk/10.3390/endocrines2020010 - 23 Apr 2021
Viewed by 1025
Abstract
Sport-related brain injury (SRBI) occurs when a blow to the head causes the brain to move back and forth in the skull, and can lead to neuroendocrine dysfunction. Research has shown that males and females experience and recover from SRBI differently, yet most [...] Read more.
Sport-related brain injury (SRBI) occurs when a blow to the head causes the brain to move back and forth in the skull, and can lead to neuroendocrine dysfunction. Research has shown that males and females experience and recover from SRBI differently, yet most of what is known regarding diagnosis, treatment, and recovery of SRBI is based on male normative data even though females meet or exceed incidence numbers of SRBIs compared to those of males. Females also have been known to have worse outcomes and a greater number of symptoms following SRBI than males. Research is limited as to why females have worse outcomes, but sex hormones have been suggested as a potential reason. SRBI may cause a dysregulation of the hypothalamic–pituitary–gonadal (HPG) axis, which is responsible for regulating the sex hormones estrogen and progesterone. Initial research has shown that SRBI may suppress estrogen and progesterone, and the concentration of these sex hormones could be indicative of injury severity and recovery trajectory. This review discusses the sex-specific differences in SRBI and also the future direction of research that is needed in order to identify the repercussions of SRBIs for female athletes, which will eventually lead to better clinical treatment, sideline care, and recovery profiles. Full article
(This article belongs to the Special Issue Exercise Endocrinology)
Review
Exercise as a Therapeutic Intervention in Gestational Diabetes Mellitus
Endocrines 2021, 2(2), 65-78; https://0-doi-org.brum.beds.ac.uk/10.3390/endocrines2020007 - 26 Mar 2021
Cited by 3 | Viewed by 1486
Abstract
Gestational Diabetes Mellitus (GDM) is defined as any degree of glucose intolerance with onset or first recognition during pregnancy. Regular exercise is important for a healthy pregnancy and can lower the risk of developing GDM. For women with GDM, exercise is safe and [...] Read more.
Gestational Diabetes Mellitus (GDM) is defined as any degree of glucose intolerance with onset or first recognition during pregnancy. Regular exercise is important for a healthy pregnancy and can lower the risk of developing GDM. For women with GDM, exercise is safe and can affect the pregnancy outcomes beneficially. A single exercise bout increases skeletal muscle glucose uptake, minimizing hyperglycemia. Regular exercise training promotes mitochondrial biogenesis, improves oxidative capacity, enhances insulin sensitivity and vascular function, and reduces systemic inflammation. Exercise may also aid in lowering the insulin dose in insulin-treated pregnant women. Despite these benefits, women with GDM are usually inactive or have poor participation in exercise training. Attractive individualized exercise programs that will increase adherence and result in optimal maternal and offspring benefits are needed. However, as women with GDM have a unique physiology, more attention is required during exercise prescription. This review (i) summarizes the cardiovascular and metabolic adaptations due to pregnancy and outlines the mechanisms through which exercise can improve glycemic control and overall health in insulin resistance states, (ii) presents the pathophysiological alterations induced by GDM that affect exercise responses, and (iii) highlights cardinal points of an exercise program for women with GDM. Full article
(This article belongs to the Special Issue Exercise Endocrinology)
Show Figures

Figure 1

Back to TopTop