Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 44
Filter
1.
Pharmacol Biochem Behav ; 175: 19-23, 2018 12.
Article in English | MEDLINE | ID: mdl-30193843

ABSTRACT

DHEA is reported to have beneficial effects for the elderly and for several pathologies because of its behavioral and anti-inflammatory properties. However, these properties have never been investigated in a young healthy population. The purpose of this double-blind, randomized study was therefore to investigate the effects of short-term DHEA administration (100 mg/day/4 weeks) on neuroendocrine (i.e., beta-endorphin and prolactin) and inflammatory (i.e., interleukin-6 and TNF-alpha) parameters in 10 young healthy female volunteers with regular sports practice. In parallel, the stress state was assessed with the Profile of Mood States (POMS) questionnaire. DHEA administration did not alter prolactin, interleukin-6 or TNF-alpha, and no significant change in tension, depression, anger, vigor, fatigue or confusion was noted. However, beta-endorphin levels increased significantly (p < 0.05) with the DHEA treatment. The results of this investigation indicate that short-term DHEA administration improves neuroendocrine modulation but does not affect the inflammatory status or psychological state in recreationally trained female athletes. Further studies are needed to determine the exact mechanisms and the responses of these parameters to DHEA administration at higher dosages and/or for longer durations, especially in response to physical/psychological stress.


Subject(s)
Dehydroepiandrosterone/administration & dosage , Inflammation/chemically induced , Neurosecretory Systems/drug effects , Double-Blind Method , Female , Humans , Stress, Physiological , Stress, Psychological , Young Adult
2.
J Sports Sci ; 36(9): 1015-1021, 2018 May.
Article in English | MEDLINE | ID: mdl-28682161

ABSTRACT

The aim of this study was to determine the influence of swim intensity on acute responses to dynamic apnoea. 9 swimmers performed one 50 m front crawl trial in four different conditions: at 400 m velocity (V400) with normal breathing (NB), at V400 in complete apnoea (Ap), at maximal velocity (Vmax) with NB and at Vmax in Ap. Peak heart rate (HRpeak), blood lactate concentration after exercise (Lacpost ex) and Borg rating of perceived exertion (RPE) were measured. Arterial oxygen saturation (SpO2) was monitored with a pulse oximeter at forehead level during and after exercise. In Ap, swimming at V400 induced a significantly lower HRpeak and Lacpost ex than swimming at Vmax whilst RPE and the kinetics of SpO2 were not different at V400 and at Vmax. The minimal value of SpO2 in Ap was reached 10 to 11 s after the end of V400 and Vmax (81.7 ± 10.1% and 84.4 ± 10.6%, respectively). Swimming a 50 m front crawl in Ap resulted in a large decrease in SpO2 which occurred only after the cessation of exercise. The higher duration of apnoea during submaximal exercise could explain why SpO2 and RPE reached the same values as for maximal exercise.​.


Subject(s)
Breath Holding , Swimming/physiology , Athletic Performance/physiology , Heart Rate/physiology , Humans , Lactic Acid/blood , Male , Oxygen/blood , Perception/physiology , Physical Conditioning, Human/methods , Physical Exertion/physiology
3.
Physiol Behav ; 164(Pt A): 68-85, 2016 10 01.
Article in English | MEDLINE | ID: mdl-27235338

ABSTRACT

The adrenal and gonadal stress steroids [i.e., cortisol, testosterone and dehydroepiandrosterone (DHEA)] have gathered considerable attention in the last few decades due to their very broad physiological and psychological actions. Their diurnal patterns have become a particular focus following new data implicating altered diurnal hormone patterns in various endocrine, behavioral and cardiovascular risk profiles. In this review of the current literature, we present a brief overview of the altered diurnal patterns of these hormones that may occur in relation to chronic stress, nutritional behaviors, physical exercise, drugs and sleep deprivation/shift. We also present data on the altered diurnal hormone patterns implicated in cardiometabolic and psychiatric/neurologic diseases, cancer and other complex pathologies. We consider the occasionally discrepant results of the studies, and summarize the current knowledge in this new field of interest, underlining the potential effects on both biological and psychological functioning, and assess the implications of these effects. Last, we conclude with some practical considerations and perspectives.


Subject(s)
Circadian Rhythm/physiology , Sleep Deprivation/metabolism , Sleep Deprivation/physiopathology , Steroids/metabolism , Animals , Cardiovascular Diseases/metabolism , Cardiovascular Diseases/pathology , Exercise/physiology , Humans , Hypothalamo-Hypophyseal System/physiopathology , Mental Disorders/metabolism , Mental Disorders/pathology , Neoplasms/metabolism , Neoplasms/pathology , Pituitary-Adrenal System/physiopathology
5.
Springerplus ; 4: 622, 2015.
Article in English | MEDLINE | ID: mdl-26543757

ABSTRACT

This study analyzed baroreflex sensitivity, heart rate and systolic blood pressure variabilities during an oral 1 week administration of prednisone. This study examined the hypothesis that prednisone might change both systolic blood pressure level and baroreflex sensitivity. Twelve physically active male subjects participated to a double-blind, randomized cross-over study consisting of two 1-week periods of treatment separated by a 4-week drug-free washout period: placebo (PLA) or prednisone (PRED). Trials were performed by each subject four times on the second (D2) and seventh (D7) day of each treatment period. ECG and blood pressure were continuously recorded to compute heart rate variability, systolic blood pressure variability and baroreflex sensitivity components with the smoothed pseudo Wigner Ville distribution and baroreflex analysis. Following D2 prednisone treatment, both HR (PLA: 60.8 ± 10.5 vs. PRED: 65.8 ± 9.1 beats min(-1), p = 0.008) and low frequency component of systolic blood pressure variability (D2: 3.09 ± 0.19 vs. D7: 2.34 ± 0.19, p < 0.041) increased whereas other components did not change. Over 7 days of treatment, LF-SBP amplitude increased (D2: 2.71 ± 0.89 vs. D7: 3.87 ± 0.6 mmHg, p = 0.037). A slight increase in both HR and LF-SBPV were observed suggesting a potential sympathetic cardiovascular stimulus. Although we found a significant effect of the 1-week prednisone treatment on heart rate and low frequency power of systolic blood pressure variability, we reported neither an increase in the systolic blood pressure level nor a decrease in the baroreflex sensitivity. Therefore, the fragility of our results cannot support a deleterious effect of 1-week administration of prednisone on the autonomic cardiovascular control which might be involved in cardiovascular diseases.

6.
Contraception ; 91(3): 245-7, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25592051

ABSTRACT

BACKGROUND: The impact of oral contraceptives (OCs) on the saliva diurnal pattern of metabolic steroid hormones remained unknown. STUDY DESIGN: Saliva samples were taken from young healthy women (11 OC users, 10 non-OC users) to analyze cortisol, dehydroepiandrosterone (DHEA) and testosterone 4 times (days 1, 8, 15 and 22) over one menstrual cycle. RESULTS: OC use decreased saliva testosterone concentrations (p<.01) under all conditions of day and time, but not saliva cortisol. OC also decreased saliva DHEA concentrations during the first part of the day (p<.05), with a dampened amplitude in its diurnal pattern. CONCLUSION: The clinical relevance requires further study.


Subject(s)
Contraceptives, Oral, Combined/metabolism , Dehydroepiandrosterone/analysis , Ethinyl Estradiol/metabolism , Hydrocortisone/analysis , Levonorgestrel/metabolism , Saliva/chemistry , Testosterone/analysis , Circadian Rhythm , Drug Combinations , Female , Humans , Menstrual Cycle/metabolism , Young Adult
7.
Horm Metab Res ; 47(7): 516-20, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25611207

ABSTRACT

Glucocorticoids are among the most commonly used drugs. They are widely administered for acute and chronic musculoskeletal pain, as well as for several other pain syndromes, although their therapeutic use is sometimes diverted for doping purposes. Their time-course effects on hormonal and inflammatory responses nevertheless remain poorly understood, both at rest and during exercise. We therefore studied the alterations induced by 1 week of prednisone treatment (60 mg daily) in recreationally trained male athletes after 2 days (i. e., acute) and 7 days (i. e., short-term). Hormonal (i. e., DHEA, DHEA-S, aldosterone, and testosterone) and pro- and anti-inflammatory markers (i. e., IL-6, IL-10, and IL-1ß) were investigated at rest and after resistance exercise. A significant decrease in DHEA and DHEA-S (p<0.01) without change in the DHEA/DHEA-S ratio, aldosterone, or testosterone was demonstrated after acute prednisone intake. A significant increment in IL-10 and a significant decrement in IL-6 (p<0.05) were also observed with prednisone both at rest and during exercise, without significant change in IL-1ß. Continued prednisone treatment led to another significant decrease in both DHEA and DHEA-S (p<0.05), whereas no change in the inflammatory markers was observed between days 2 and 7. Our data demonstrate that the anti-inflammatory effects of prednisone were maximal and stable from the beginning of treatment, both in rest and exercise conditions. However, hormonal concentrations continued to decline during short-term intake. Further studies are needed to determine the effects of hormonal time-course alterations with longer glucocorticoid treatment and the clinical consequences.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Exercise/physiology , Prednisone/pharmacology , Aldosterone/blood , Athletes , Cross-Over Studies , Dehydroepiandrosterone/blood , Dehydroepiandrosterone Sulfate/blood , Double-Blind Method , Glucocorticoids , Humans , Hydrocortisone , Interleukin-10/blood , Interleukin-1beta/blood , Interleukin-6/blood , Male , Resistance Training , Rest , Testosterone/blood , Young Adult
8.
J Steroid Biochem Mol Biol ; 145: 206-12, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24704255

ABSTRACT

The dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) concentrations during acute and chronic exercise (training) have been investigated only fairly recently. DHEA is generally preferred to DHEA-S for exploring the acute exercise repercussions in laboratory or field tests because of its shorter elimination half-life. Conversely, DHEA-S is preferred to estimate chronic adaptations. Both can be measured noninvasively in saliva, and it is therefore possible to follow these hormone responses in elite athletes during competitive events and in healthy and pathological populations, without imposing additional stress. Indeed, the correlation between saliva and serum concentrations is high for steroid hormones, both at rest and during exercise. In this review, we will first summarize the current knowledge on the DHEA/DHEA-S responses to exercise and examine the potential modulating factors: exercise intensity, gender, age, and training. We will then discuss the ergogenic effects that athletes expect from the exogenous administration of DHEA and the antidoping methods of analysis currently used to detect this abuse.


Subject(s)
Aging , Dehydroepiandrosterone/metabolism , Doping in Sports , Exercise , Age Factors , Athletes , Dehydroepiandrosterone/blood , Dehydroepiandrosterone Sulfate/blood , Dehydroepiandrosterone Sulfate/metabolism , Dietary Supplements , Female , Humans , Male , Substance Abuse Detection
9.
Endocrine ; 46(3): 668-71, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24347241

ABSTRACT

Significant alteration in hypothalamic-pituitary-adrenal function has been demonstrated in patients after short-term glucocorticoid therapy, but its impact on the circadian rhythm of steroid hormones has never been investigated. This study examined the effects of short-term prednisone administration on the diurnal patterns of dehydroepiandrosterone (DHEA) and testosterone. Saliva samples were collected from 11 healthy, physically active, male volunteers for DHEA and testosterone analysis, as follows: every 4 h from 0800 to 2000 h on 2 control days without medication, and after 1 week of oral therapeutic prednisone treatment (60 mg daily) (days 0-3). Overall, a diurnal decline in the two steroid hormones was observed on the control days. After short-term glucocorticoid administration, DHEA concentrations were significantly decreased with a complete disappearance of the DHEA diurnal pattern, which lasted 2 days post-treatment. No glucocorticoid effect was observed for testosterone. The results indicate that short-term prednisone treatment affects the circadian pattern of saliva DHEA but not testosterone in healthy active volunteers. Further studies are necessary to determine whether this alteration in DHEA circadian pattern has clinical consequences in patients with chronic glucocorticoid therapy.


Subject(s)
Circadian Rhythm/drug effects , Dehydroepiandrosterone/analysis , Glucocorticoids/administration & dosage , Saliva/chemistry , Circadian Rhythm/physiology , Humans , Male , Testosterone/analysis , Young Adult
10.
Stress ; 16(2): 261-5, 2013 Mar.
Article in English | MEDLINE | ID: mdl-22734443

ABSTRACT

Diurnal patterns of cortisol and dehydroepiandrosterone (DHEA) secretion, the two main peripheral secretory products of the hypothalamic-pituitary-adrenal neuroendocrine stress axis, have been well characterized in rest conditions but not in relation to physical exercise. The purpose of this investigation was therefore to determine the effects of an intense 90-min aerobic exercise on the waking diurnal cortisol and DHEA cycles on three separate days [without exercise, with morning exercise (10:00-11:30 h), and with afternoon exercise (14:00-15:30 h)] in nine recreationally trained soccer players. Saliva samples were collected at awakening, 30 min after awakening, and then every 2 h from 08:00 to 22:00 h. A burst of secretory activity was found for cortisol (p < 0.01) but not for DHEA after awakening. Overall, diurnal decline for both adrenal steroids was observed on resting and exercise days under all conditions. However, there was a significant increase in salivary cortisol concentrations on the morning-exercise and afternoon-exercise days at, respectively, 12:00 h (p < 0.05) and 16:00 h (p < 0.01), versus the other trials. This acute response to exercise was not evident for DHEA. The results of this investigation indicate that 90 min of intense aerobic exercise does not affect the circadian pattern of salivary adrenal steroids in recreationally trained athletes over a 16-h waking period, despite a transitory increase in post-exercise cortisol concentration. Further studies are necessary to determine whether these results are applicable to elite athletes or patients with cortisol or DHEA deficiency.


Subject(s)
Circadian Rhythm/physiology , Dehydroepiandrosterone/metabolism , Exercise/physiology , Hydrocortisone/metabolism , Saliva/chemistry , Soccer , Humans , Male , Pituitary-Adrenal System/physiology , Rest , Young Adult
11.
Horm Metab Res ; 44(2): 146-51, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22173991

ABSTRACT

The purpose of the study was to assess the effects of aerobic exercise training on saliva steroid hormones [i. e., cortisol, dehydroepiandrosterone (DHEA), and testosterone], physical capacity, and quality of life in obese diabetic men. 8 abdominally obese type 2 diabetic men (59.5±1.7 years old, BMI=35.5±1.6 kg/m(2), waist circumference=119.4±3.3 cm) and 9 healthy men (57.4±1.5 years old, BMI=24.5±0.8 kg/m(2), waist circumference=92.3±1.9 cm) participated in the study. The obese diabetic men underwent 8 weeks of aerobic exercise training: twice a week 45 min sessions at 75% of peak heart rate and once a week 45 min session of intermittent exercise. Before and after training, steroid hormone concentrations were analyzed from saliva samples, physical capacity was assessed by the 6-minute walking test, and quality of life was estimated by a specific questionnaire for obese subjects. These data were compared with the data from the healthy untrained men. The basal saliva DHEA and testosterone concentrations, physical capacity, and quality of life scores of the obese diabetic men were significantly lower than those of the healthy men. Aerobic training induces a significant increase in the 6-min walking distance and improve the psychosocial impact dimension of quality of life, without modifying significantly any other parameter investigated. These data suggest that an 8-week aerobic exercise program improves physical capacity and quality of life in obese diabetic men, but was insufficient to correct the anthropometric and hormonal alterations observed in this population.


Subject(s)
Diabetes Mellitus, Type 2/metabolism , Exercise/physiology , Obesity/metabolism , Saliva/metabolism , Dehydroepiandrosterone/metabolism , Diabetes Mellitus, Type 2/psychology , Exercise/psychology , Humans , Hydrocortisone/metabolism , Male , Middle Aged , Obesity/psychology , Quality of Life/psychology , Statistics, Nonparametric , Surveys and Questionnaires , Walking/physiology , Walking/psychology
12.
Horm Metab Res ; 43(3): 216-22, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21234852

ABSTRACT

The aim of the study was to evaluate the effects of short-term glucocorticoid treatment on plasma amino acids, free fatty acids, blood glucose, and several hormones in healthy volunteers performing long-lasting exercise. 9 young female subjects exercised 2 h at 50-55% VO2 max twice, once after placebo (Pla) ingestion and once after prednisone (Cor, 50 mg/day/7 days) ingestion, according to a double-blind and randomized protocol. Blood samples were tat rest and during exercise for measurement of amino acids, free fatty acids, blood glucose, adrenocorticotrophic hormone (ACTH), growth hormone, dehydroepiandrosterone (DHEA), insulin, and glucagon. Both ACTH and DHEA values were significantly decreased by Cor vs. Pla (p < 0.01) throughout exercise, and Cor intake also induced lower growth hormone concentrations vs. Pla (p < 0.05) from 60 min to the end of exercise. No significant difference in glucagon, insulin or free fatty acid values was found between the treatments. Branched-chain amino acids and other essential amino acids were significantly higher after Cor vs. Pla from 60 min to the end of exercise (p < 0.05), whereas blood glucose was significantly higher from 90 min to the end of exercise (p < 0.05). We conclude that short-term glucocorticoid intake induces marked hormonal and metabolic changes during long-lasting exercise. Proteolysis can increase with glucocorticoid during this type of exercise and the related higher plasma amino acid concentrations may contribute as energy substrates. Further studies will be necessary to explore and accurately quantify the mechanisms of proteolysis and glyconeogenesis induced by short-term glucocorticoid intake during this type of exercise.


Subject(s)
Amino Acids/blood , Blood Glucose/analysis , Exercise , Fatty Acids, Nonesterified/blood , Glucocorticoids/administration & dosage , Hormones/blood , Female , Humans , Time Factors , Young Adult
13.
Horm Metab Res ; 43(2): 148-50, 2011 Feb.
Article in English | MEDLINE | ID: mdl-20925016

ABSTRACT

The aim of this study was to evaluate serum and saliva adrenocortical hormones and their relationships at rest and during submaximal exercise and recovery in 9 obese diabetic middle-aged men (BMI: 35.2 ± 1.6 kg/m (2)). Blood and saliva samples were taken at rest, every 10 min of a 30-min cycling exercise at 70% of maximal heart rate, and after 10 min of recovery in order to analyze cortisol, dehydroepiandrosterone sulfate (DHEA-S) and dehydroepiandrosterone (DHEA). Serum and saliva cortisol increased significantly during recovery (p<0.05), but no significant difference was observed between the rest, exercise, and recovery DHEA-S and DHEA concentrations. A strong correlation was found at rest between both serum and saliva cortisol (r=0.72, p<0.001) and DHEA-S and DHEA (r=0.93, p<0.001). Serum DHEA-S and saliva DHEA remained strongly correlated during and after the submaximal exercise (r=0.81, p<0.001), whereas a weaker but still significant relationship was observed between serum and saliva cortisol during and after the exercise (r=0.52, p<0.001). In conclusion, these results suggest that saliva adrenocortical hormones, and especially saliva DHEA, may offer a practical surrogate for serum concentrations during both rest and exercise in obese diabetic men.


Subject(s)
Dehydroepiandrosterone Sulfate/metabolism , Dehydroepiandrosterone/metabolism , Diabetes Mellitus/metabolism , Exercise , Hydrocortisone/metabolism , Obesity/metabolism , Saliva/chemistry , Dehydroepiandrosterone/blood , Dehydroepiandrosterone Sulfate/blood , Diabetes Mellitus/blood , Humans , Hydrocortisone/blood , Male , Middle Aged , Obesity/blood
14.
J Physiol Sci ; 60(6): 435-9, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20809140

ABSTRACT

This study examined the relationships between plasma and saliva adrenocortical hormones in response to long-duration submaximal exercise. In nine healthy, physically active, female volunteers, blood and saliva samples were taken at rest and every 30 min during a 120-min cycling trial at 50-55% VO(2max) for cortisol and dehydroepiandrosterone (DHEA) analysis. Correlation analysis revealed a moderate but significant relationship between plasma and saliva cortisol (r = 0.35, P < 0.02) and plasma and saliva DHEA (r = 0.47, P < 0.001) during the submaximal exercise. When expressed in percent of resting values, the correlations between the plasma and saliva concentrations were higher for both hormones during the exercise (cortisol: r = 0.72; DHEA: r = 0.68, P < 0.001). The results thus suggest that, even under prolonged exercise conditions, non-invasive saliva samples may offer a practical approach to assessing pituitary-adrenal function, especially when compared with individual basal values.


Subject(s)
Dehydroepiandrosterone/analysis , Dehydroepiandrosterone/blood , Exercise/physiology , Hydrocortisone/analysis , Hydrocortisone/blood , Saliva/chemistry , Bicycling , Female , Humans , Young Adult
15.
Stress ; 13(6): 528-32, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20666655

ABSTRACT

The purpose of this study was to examine salivary cortisol, dehydroepiandrosterone (DHEA), and testosterone responses to the bench press in an international powerlifting competition and to determine whether these salivary hormone concentrations could be used to predict performance. Twenty-six elite athletes (13 females and 13 males) provided saliva samples during the official weighing-in and after the last attempt at the bench press, as well as at baseline on a non-competition day. Performance index was determined with the Wilks formula, which adjusts powerlifting scores according to body mass. Salivary cortisol concentrations were significantly increased in all subjects after the bench press (p < 0.01), whereas DHEA concentrations were significantly increased in women (p < 0.01) but not in men after the bench press. No significant change in testosterone concentrations was observed during the experiment in either men or women, which resulted in a marked decrease in the testosterone/cortisol ratio. The performance index showed no significant correlation with any of the hormone responses to competition. In conclusion, despite the increase in stress adrenocortical hormone responses to an international powerlifting competition, these hormone concentrations alone are not predictors of bench press performance in elite powerlifting athletes.


Subject(s)
Dehydroepiandrosterone/metabolism , Hydrocortisone/metabolism , Saliva/metabolism , Testosterone/metabolism , Weight Lifting/physiology , Adult , Female , Humans , Hypothalamo-Hypophyseal System/physiology , Male , Pituitary-Adrenal System/physiology
16.
Eur J Clin Invest ; 40(2): 183-6, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19874391

ABSTRACT

BACKGROUND: Given the high correlation between the serum and saliva hormone values demonstrated at rest, saliva provides a convenient non-invasive way to determine dehydroepiandrosterone (DHEA) and cortisol concentrations. However, to our knowledge, pituitary adrenal recovery following short-term suppression with corticosteroids has never been investigated in saliva. The aim of this study was therefore to examine how steroid hormone concentrations in saliva are influenced by short-term corticosteroid administration. MATERIALS AND METHODS: We studied saliva DHEA and cortisol concentrations before, during (day 1-day 7) and following (day 8-day 16) the administration of oral therapeutic doses of prednisone (50 mg daily for 1 week) in 11 healthy recreationally trained women. RESULTS: Mean saliva DHEA and cortisol concentrations decreased immediately after the start of prednisone treatment (P < 0.05). Three days after concluding prednisone administration, both saliva DHEA and cortisol had returned to pretreatment levels. CONCLUSIONS: These data are consistent with previous studies on blood samples and suggest that non-invasive saliva samples may offer a practical approach to assessing pituitary-adrenal function continuously during and after short-term corticosteroid therapy.


Subject(s)
Dehydroepiandrosterone/metabolism , Glucocorticoids/administration & dosage , Hydrocortisone/metabolism , Prednisone/administration & dosage , Saliva/metabolism , Adult , Enzyme-Linked Immunosorbent Assay , Female , Humans , Young Adult
17.
Eur J Appl Physiol ; 105(2): 207-13, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18925413

ABSTRACT

In order to test the hypothesis that salbutamol would change substrate oxidation during submaximal exercise, eight recreationally trained men twice performed 1 h at 60% VO(2) peak after ingestion of placebo or 4 mg of salbutamol. Gas exchange was monitored and blood samples were collected during exercise for GH, ACTH, insulin, and blood glucose and lactate determination. With salbutamol versus placebo, there was no significant difference in total energy expenditure and substrate oxidation, but the substrate oxidation balance was significantly modified after 40 min of exercise. ACTH was significantly decreased with salbutamol during the last 10 min of exercise, whereas no difference was found between the two treatments in the other hormonal and metabolic parameters. The theory that the ergogenic effect of salbutamol results from a change in substrate oxidation has little support during relatively short term endurance exercise, but it is conceivable that longer exercise duration can generate positive findings.


Subject(s)
Albuterol/pharmacology , Oxidation-Reduction/drug effects , Physical Endurance/drug effects , Physical Endurance/physiology , Adrenocorticotropic Hormone/blood , Blood Glucose , Exercise/physiology , Growth Hormone/blood , Humans , Insulin/blood , Lactic Acid/blood , Male , Physical Exertion/drug effects , Physical Exertion/physiology , Time Factors , Young Adult
18.
Eur J Appl Physiol ; 105(2): 309-13, 2009 Jan.
Article in English | MEDLINE | ID: mdl-18985374

ABSTRACT

In order to test the hypothesis that short-term corticoid intake alters food intake, body composition and adipokines secretion in healthy volunteers with regular sport practice, nutrient intake was assessed in eight male athletes with and without prednisolone (PRED, 60 mg/day for 1 week) ingestion in a random, double blind, crossover design. Body weight, body composition, adipokines (i.e., leptin, adiponectin and TNF-alpha), insulin and blood glucose were determined before and at the end of each treatment. PRED did not induce any significant change in body weight, body composition or food intake. Insulin and TNF-alpha were not significantly altered with PRED compared to placebo but blood glucose, leptin and adiponectin concentrations at rest appear significantly increased after PRED treatment (P < 0.05). Our data show that 1 week glucocorticoid treatment does not promote obesity in recreationally trained men but further studies are necessary to understand its effects on the metabolically active hormones, leptin and adiponectin.


Subject(s)
Adiponectin/blood , Eating/drug effects , Leptin/blood , Prednisolone/pharmacology , Tumor Necrosis Factor-alpha/blood , Blood Glucose , Body Composition/drug effects , Body Weight/drug effects , Cross-Over Studies , Double-Blind Method , Humans , Insulin/blood , Male , Random Allocation , Young Adult
19.
Br J Sports Med ; 42(4): 250-4; discussion 254, 2008 Apr.
Article in English | MEDLINE | ID: mdl-17609220

ABSTRACT

OBJECTIVE: To examine whether acute glucocorticoid (GC) intake alters performance and selected hormonal and metabolic variables during submaximal exercise. METHODS: In total, 14 recreational male athletes completed two cycling trials at 70-75% maximum O(2) uptake starting 3 h after an ingestion of either a lactose placebo or oral GC (20 mg of prednisolone) and continuing until exhaustion, according to a double-blind randomised protocol. Blood samples were collected at rest, after 10, 20, 30 minutes, and at exhaustion and recovery for measurement of growth hormone (GH), adrenocorticotropic hormone (ACTH), dehydroepiandrosterone (DHEA), prolactin, insulin, blood glucose, lactate and interleukin (IL)-6 determination. RESULTS: Cycling duration was not significantly changed after GC or placebo administration (55.9 (5.2) v 48.8 (2.9) minutes, respectively). A decrease in ACTH and DHEA (p<0.01) was observed with GC during all of the experiments and in IL-6 after exhaustion (p<0.05). No change in basal, exercise or recovery GH, prolactin, insulin or lactate was found between the two treatments but blood glucose was significantly higher with GC (p<0.05) at any time point. CONCLUSION: From these data, acute systemic GC administration does seem to alter some metabolic markers but did not influence performance during submaximal exercise.


Subject(s)
Athletic Performance/physiology , Bicycling/physiology , Energy Metabolism/drug effects , Glucocorticoids/pharmacology , Physical Endurance/drug effects , Prednisolone/pharmacology , Adult , Double-Blind Method , Energy Metabolism/physiology , Exercise/physiology , Glucocorticoids/administration & dosage , Humans , Male , Physical Endurance/physiology , Physical Exertion/drug effects , Physical Exertion/physiology , Prednisolone/administration & dosage
20.
Int J Sports Med ; 29(1): 21-6, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17614029

ABSTRACT

We examined the hypothesis that acute therapeutic glucocorticoid intake could change the contribution of fat and carbohydrate (CHO) in energy production during exercise. Nine healthy recreationally-trained male subjects twice performed submaximal exercise (60 min at 60 % VO2max) after ingestion of placebo (Pla) or 20 mg of prednisolone (Pred), according to a double blind and randomized protocol. Respiratory exchange was monitored during exercise and blood samples were collected at rest, every 10 min during exercise and after 5, 10, and 20 min of passive recovery. Pred intake significantly increased total energy expenditure during exercise, but CHO oxidation was lower and fat oxidation higher after Pred vs. Pla. ACTH and IL-6 concentrations were significantly decreased with Pred during exercise, whereas no variations were found in GH, insulin, blood glucose, and lactate between the 2 treatments. In conclusion, it appears that acute prednisolone systemic administration does reduce total carbohydrate oxidation during submaximal exercise. Further studies are necessary to clarify the mechanisms involved and to determine whether this modification in the substrate oxidation balance under glucocorticoid administration in recreationally-trained male subjects could result in a competitive advantage in elite athletes.


Subject(s)
Energy Metabolism/drug effects , Exercise/physiology , Glucocorticoids/pharmacology , Prednisolone/pharmacology , Adrenocorticotropic Hormone/blood , Adrenocorticotropic Hormone/drug effects , Adult , Blood Glucose/drug effects , Carbohydrate Metabolism/drug effects , Cross-Over Studies , Double-Blind Method , Fats/metabolism , Growth Hormone/blood , Humans , Insulin/blood , Interleukin-6/blood , Lactic Acid/blood , Male , Middle Aged , Oxidation-Reduction
SELECTION OF CITATIONS
SEARCH DETAIL