A. Arlettaz

Effects of acute salbutamol intake during supramaximal exercise in women.

Objective: To study the effects of an acute therapeutic oral intake of β2 agonist on performance and substrate response during supramaximal exercise in women. Methods: 12 healthy moderately trained female volunteers performed a Wingate test after ingestion of placebo (Pla) and salbutamol (Sal; 4 mg) according to a double-blind randomised crossover study. Blood samples were collected at rest, at the end of exercise and after 5 (r5), 10 (r10) and 15 (r15) min of passive recovery for adrenocorticotropic hormone (ACTH), growth hormone (GH), insulin, blood glucose and lactate measurements. Results: Peak power (PP) and mean power (MP) significantly increased whereas time to peak power was significantly shorter with Sal than with Pla (p<0.05). No change was observed in the fatigue index. ACTH was not significantly modified but r15 growth hormone significantly decreased (p<0.05) after the intake of Sal. Both blood INS and blood glucose were significantly increased by the intake of Sal during all the experiments (p<0.01). Blood lactate was significantly increased by the intake of Sal compared with that of Pla (p<0.05) after 10 and 15 min of passive recovery. Conclusion: From these data, acute therapeutic oral intake of Sal seems to induce, irrespective of the subjects’ gender, an improvement in performance during a supramaximal exercise—that is, increase in PP and MP. Further studies are necessary to clarify whether the mechanisms involved in the response to intake of Sal are linked to central and/or peripheral pathways.

Effects of short-term corticoid ingestion on food intake and adipokines in healthy recreationally trained men.

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, 60xa0mg/day for 1xa0week) ingestion in a random, double blind, crossover design. Body weight, body composition, adipokines (i.e., leptin, adiponectin and TNF-α), 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-α were not significantly altered with PRED compared to placebo but blood glucose, leptin and adiponectin concentrations at rest appear significantly increased after PRED treatment (Pxa0<xa00.05). Our data show that 1xa0week 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.

Short-term glucocorticoid intake combined with intense training on performance and hormonal responses

Objective: To investigate the effects of short-term prednisolone ingestion combined with intense training on exercise performance, hormonal (adrenocorticotrophic hormone (ACTH), prolactin, luteinising hormone (LH), growth hormone (GH), thyroid-stimulating hormone (TSH), dehydroepiandrosterone (DHEA), testosterone, insulin) and metabolic parameters (blood glucose, lactate, bicarbonate, pH). Methods: Eight male recreational athletes completed four cycling trials at 70–75% peak O2 consumption until exhaustion just before (1) and after (2) either oral placebo or prednisolone (60 mg/day for 1 week) treatment coupled with standardised physical training (2 hours/day), according to a double-blind and randomised protocol. Blood samples were collected at rest, during exercise and passive recovery for the hormonal and metabolic determinations. Results: Time of cycling was not significantly changed after placebo but significantly increased (p<0.05) after prednisolone administration (50.4 (6.2) min for placebo 1, 64.0 (9.1) min for placebo 2, 56.1 (9.1) min for prednisolone 1 and 107.0 (20.7) min for prednisolone 2). There was no significant difference in any measured parameters after the week of training with placebo but a decrease in ACTH, DHEA, PRL, GH, TSH and testosterone was seen with prednisolone treatment during the experiment (p<0.05). No significant change in basal, exercise or recovery LH, insulin, lactate, pH or bicarbonate was found between the two treatment, but blood glucose was significantly higher under prednisolone (p<0.05) at all time points. Conclusion: Short-term glucocorticoid administration induced a marked improvement in endurance performance. Further studies are needed to determine whether these results obtained in recreational male athletes maintaining a rigorous training schedule are gender-dependent and applicable to elite athletes.

Short-term salbutamol ingestion and supramaximal exercise in healthy women

Objective: To test the hypothesis that chronic salbutamol intake improves performance during supramaximal exercise and to estimate the effects of this treatment on body composition, bone mass, and metabolic indices in healthy women. Methods: Fourteen female volunteers (seven sedentary and seven recreationally trained) performed a 30 second Wingate test with and without salbutamol ingestion (12 mg/day for four weeks) in a random, double blind, crossover design. Blood samples were collected at rest, at the end of the test, and during passive recovery for lactate measurement. Body composition and bone mass were determined by dual energy x ray absorptiometry. Results: Peak power appeared significantly earlier and was significantly (p<0.05) increased after salbutamol intake in all subjects. There was no difference in total work performed and fatigue indices with salbutamol compared with placebo. No significant alterations in lean or fat body mass and bone variables were observed with salbutamol treatment in either trained or untrained subjects during the trial. In contrast, blood lactate was significantly (p<0.05) increased during the recovery period after salbutamol ingestion compared with placebo. Conclusion: As in men, chronic administration of therapeutic concentrations of salbutamol did not induce an anabolic effect in women but increased maximal anaerobic power. Further studies are necessary to clarify the mechanisms involved.

Effects of acute prednisolone administration on exercise endurance and metabolism

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 O2 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.

Salbutamol intake and substrate oxidation during submaximal exercise

In order to test the hypothesis that salbutamol would change substrate oxidation during submaximal exercise, eight recreationally trained men twice performed 1xa0h at 60% VO2 peak after ingestion of placebo or 4xa0mg 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 40xa0min of exercise. ACTH was significantly decreased with salbutamol during the last 10xa0min 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.

Glucocorticoid administration in athletes: Performance, metabolism and detection

It is generally acknowledged in the sporting world that glucocorticoid (GC) use enhances physical performance. This pharmacological class is therefore banned by the World Anti-Doping Agency (WADA) in in-competition samples after systemic but not local (defined as any route other than oral, intravenous, intramuscular or rectal) administration, which thus allows athletes to use GCs for therapeutic purposes. According to the 2016 WADA list, the urine reporting level for all GCs is set at 30ng/ml to distinguish between the authorized and banned routes of administration. The actual data on the ergogenic effects of GC intake are nevertheless fairly recent, with the first study showing improved physical performance with systemic GC administration dating back only to 2007. Moreover, the studies over the last decade coupling ergogenic and metabolic investigations in humans during and after GC intake have shown discrepant results. Similarly, urine discrimination between banned and authorized GC use remains complex, but it seems likely to be improved thanks to new analytical studies and the inclusion of the authorized GC uses (local routes of administration and out-of-competition samples) in the WADA monitoring program. In this review, we first summarize the current knowledge on the ergogenic and metabolic GC effects in humans during various types of exercise. We then present the antidoping legislation and methods of analysis currently used to detect GC abuse and conclude with some practical considerations and perspectives.