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Labsy Z.,University Paris - Sud | Prieur F.,University Paris - Sud | Le Panse B.,University Paris - Sud | Do M.-C.,University Paris - Sud | And 3 more authors.
Stress | Year: 2013

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. © Informa Healthcare USA, Inc. Source


Le Panse B.,University Paris - Sud | Labsy Z.,University Paris - Sud | Baillot A.,University Paris - Sud | Vibarel-Rebot N.,University Paris - Sud | And 4 more authors.
Steroids | Year: 2012

The purpose of this study was to assess changes in the steroid hormone levels of elite athletes during an international powerlifting competition. Baseline cortisol, DHEA and testosterone were determined in saliva samples in 19 (8 men, 11 women) junior and sub-junior athletes on the day before competition, and then on the competition day during the official weighing and in the hour after competition. Performance was determined by total output and the Wilks formula. No change in saliva steroid concentrations was observed between samples collected on the day before competition and the weighing samples. There was no gender effect on cortisol concentrations but saliva testosterone levels were always significantly higher in men than in women (p < 0.01), as was end-competition DHEA (p < 0.05). Cortisol and DHEA were significantly increased in male and female athletes after the competition (respectively, p < 0.01 and p < 0.05), whereas end-competition testosterone concentrations were only significantly increased in men (p < 0.01). Significant relationships were demonstrated between performance and end-competition cortisol levels in women and end-competition testosterone levels in men. These data indicate that workouts during an international powerlifting competition produce a significant increase in adrenal steroid hormones in both genders, with an increase in male gonadal steroid hormone. Further studies are necessary to examine the changes in oestradiol and progesterone in women and their potential impact on performance during international powerlifting competition. © 2012 Elsevier Inc. All rights reserved. Source


Guimard A.,University Paris - Sud | Vibarel-Rebot N.,University Paris - Sud | Prieur F.,University Paris - Sud | Baillot A.,University Paris - Sud | And 4 more authors.
Science and Sports | Year: 2013

Objective: The aim of this study was to determine the effects of obesity on the waking diurnal testosterone and dehydroepiandrosterone (DHEA) cycles in obese middle-aged male subjects. Methods: Saliva samples were collected at awakening and every 3 hours from 9:00 to 21:00. hours on 2 consecutive days in eight obese non-diabetic and eight healthy non-obese control men. Results: Saliva parameters showed day-to-day consistency, with an overall diurnal decline, except for testosterone in the obese group. Saliva testosterone concentrations were significantly lower (P< 0.05) at awakening, 9:00 and 12:00. hours in obese versus control subjects. No significant differences were observed in saliva DHEA concentrations between the obese and control subjects at any time of day. Conclusion: The results of this investigation indicate that obesity alone does not affect the concentrations or the diurnal pattern of DHEA in middle-aged men, whereas the diurnal pattern of testosterone appears altered in this population, with significantly lower values during the first part of the day. © 2013 Elsevier Masson SAS. Source


Zorgati H.,University Paris - Sud | Prieur F.,University Paris - Sud | Vergniaud T.,University Paris - Sud | Cottin F.,University Paris - Sud | And 6 more authors.
Steroids | Year: 2014

All systemically administered glucocorticoids (GC) are prohibited in-competition, because of the potential ergogenic effects. Although short-term GC intake has been shown to improve performance during submaximal exercise, literature on its impact during brief intense exercise appears to be very scant. The purpose of this study was to examine the ergogenic and metabolic effects of prednisone during repeated bouts of high-intensity exercise. In a double-blind randomized protocol, ten recreational male athletes followed two 1-week treatments (Cor: prednisone, 60 mg/day or Pla: placebo). At the end of each treatment, they hopped on their dominant leg for 30 s three times consecutively and then hopped until exhaustion, with intervals of 5 min of passive recovery. Blood and saliva samples were collected at rest and 3 min after each exercise bout to determine the lactate, interleukin-6, interleukin-10, TNF-alpha, DHEA and testosterone values. The absolute peak force of the dominant leg was significantly increased by Cor but only during the first 30-s hopping bout (p < 0.05), whereas time to exhaustion was not significantly changed after Cor treatment vs Pla (Pla: 119.9 ± 24.7; Cor: 123.1 ± 29.5 s). Cor intake lowered basal and end-exercise plasma interleukin-6 and saliva DHEA (p < 0.01) and increased interleukin-10 (p < 0.01), whereas no significant change was found in blood lactate and TNF-alpha or saliva testosterone between Pla and Cor. According to these data, short-term glucocorticoid intake did not improve endurance performance during repeated bouts of high-intensity exercise, despite the significant initial increase in absolute peak force and anti-inflammatory effect. © 2014 Elsevier Ltd. All rights reserved. Source


Vibarel-Rebot N.,University Paris - Sud | Rieth N.,University Paris - Sud | Lasne F.,AFLD | Jaffre C.,University of Rennes 2 - Upper Brittany | Collomp K.,University Paris - Sud
Contraception | Year: 2015

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. © 2015 Elsevier Inc. All rights reserved. Source

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