Background: Physical activity is one of the lifestyle-related factors that is decisive for the quality of sleep and for immune system stimulation. Research question: The purpose of this research is to evaluate the effect of high-intensity endurance and strength exercises, carried out in the morning, on the quality of nighttime sleep. Methods: Fifteen healthy, trained, males were assessed at rest and during endurance and strength exercises. Preliminarily, at least one week before testing began, maximal oxygen uptake (VO2max) and maximal upper limb strength (maximal weight load, WLmax) were assessed. During each test session continuous monitoring by means of an actigraph for the rest-activity measurement was collected. Results: A single session of strength or endurance exercise positively influenced the parameters related to sleep patterns. The positive effects were particularly evident during the night immediately following the exercise. Both exercise typologies positively influenced the parameters, indicative of the total amount of sleep (assumed sleep and sleep latency). The quality of sleep, evaluated by means of number of sleep bouts, number of immobile phases, and the number of minutes immobile respectively, was also clearly improved during the first night for both types of physical activity. Sleep efficiency was significantly higher during the first and second nights respectively but only following endurance exercise. None of the parameters of sleep have highlighted statistically significant differences between the strength and the endurance sessions. Conclusions: This study shows that morning physical activity has an effect on nighttime rest, making it easier to fall asleep, lengthening the real time of sleep, and improving overall sleep quality.

Intense physical exercise activates the hypothalamic-pituitary-adrenocortical axis but little is known about changes in glucocorticoid sensitivity at the target cell level. No data are available on the acute effects of exercise on 11beta-hydroxysteroid dehydrogenase (11beta-HSD) type 1 activity, which generates biologically active cortisol from inactive cortisone and is expressed also in skeletal muscle. Fifteen healthy, trained males (age mean +/- SE 28 +/- 1) were assessed on three non-consecutive days: at rest, during an endurance and strength sessions. During each session, between 1000 and 1600 hours, 6-h urine and four salivary samples were collected. Urinary total tetrahydrocortisol (THF) + alloTHF, tetrahydrocortisone (THE), cortisol (F) and cortisone (E) were measured with HPLC-tandem mass spectrometry; urinary-unconjugated F and E were measured by HPLC-UV. Salivary cortisol and interleukin (IL)-6 were measured by RIA and ELISA, respectively. Both endurance and strength exercises caused an increase in (THF + alloTHF)/THE ratio (mean +/- SE 1.90 +/- 0.07 and 1.82 +/- 0.05 vs. 1.63 +/- 0.06, P < 0.01 and P = 0.03, respectively), consistent with increased systemic 11beta-HSD type 1 activity. No relationship was found with age, BMI, VO(2max) maximal power load or perceived exertion. No significant change was apparent in F/E ratio, an index of 11beta-HSD type 2 activity. No effect of exercise on salivary cortisol and IL-6 was observed, whereas a significant effect of sampling time was found. Intense physical exercise acutely increases systemic 11beta-HSD type 1 activity in humans. Such an increase may lead to higher cortisol concentration in target tissues, notably in skeletal muscle where it could contribute to limit exercise-induced muscle inflammatory response.