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Antioxidant supplementation has become a common practice among athletes to boost sport achievement. Likewise, melatonin (MEL) has been ingested as an ergogenic aid to improve physical performance. To date, no study has checked whether the multiple beneficial effects of MEL have an outcome during a maximum running exercise until exhaustion. Therefore, the present study aimed to evaluate the effect of MEL ingestion on physical performance and biochemical responses (i.e., oxidative stress) during exhaustive exercise. In a double blind randomized study, thirteen professional soccer players [age: 17.5 ± 0.8 years, body mass: 70.3 ± 3.9 kg, body height: 1.80 ± 0.08 m; maximal aerobic speed (MAS): 16.85 ± 0.63 km/h; mean ± standard deviation], members of a first league squad, performed a running exercise until exhaustion at 100% of MAS, after either MEL or placebo ingestion. Physical performance was assessed, and blood samples were obtained at rest and following the exercise. Compared to placebo, MEL intake prevented the increase in oxidative stress markers (i.e., malondialdehyde), alleviated the alteration of antioxidant status (i.e., glutathione peroxidase, uric acid and total bilirubin) and decreased post-exercise biomarkers of muscle damage (i.e., creatine kinase and lactate dehydrogenase) (p0.05). However, physical performance was not affected by MEL ingestion (p0.05). In conclusion, acute MEL intake before a maximal running exercise protected athletes from oxidative stress and cellular damage but without an effect on physical performance.

Background. Systemic and airway inflammation has recently been linked to obstructive sleep apnea-hypopnea syndrome (OSAHS) and is considered to be a probable risk factor for OSAHS-induced cardiovascular damage. High-sensitivity C-reactive protein (hs-CRP), as an inflammatory mediator, may be useful for the prediction of the risk of cardiovascular disease (CVD) and assessment of nocturnal continuous positive airway pressure (nCPAP) therapy effect in OSAHS patients. Methods. A prospective, controlled, cross-sectional study was conducted on 64 consecutive adult subjects with suspected sleep-disordered breathing (SDB). Results. OSAHS was confirmed in 43 patients (24 normotensive and 19 hypertensive patients) and ruled out in 21 normotensive subjects (controls). The median plasma level of hs-CRP did not differ significantly between OSAHS patients and controls. It showed an unmarked rise with the severity of OSAHS ( p = 0.20 ) and was not correlated with AHI ( p = 0.067 ; r = 0.28 ). After adjusting for cervical perimeter (CP), waist-to-hip ratio (WHR), and blood sugar level, hs-CRP level of 1 mg/dL or greater was significantly more often observed in OSAHS patients compared with controls ( p = 0.032 ; OR = 5.60 ) and was also significantly associated with AHI ( p = 0.021 ). A significant decrease in the median plasma hs-CRP level was observed in CPAP compliant patients ( p = 0.006 ). Of those, only normotensive patients showed a significant decrease in plasma hs-CRP level. In hypertensive ones, however, the hs-CRP level dropped but not significantly. Using a linear regression model, the change in hs-CRP level (Δhs-CRP) following a 6-month-nCPAP therapy was found to positively correlate with the baseline hs-CRP level for both hypertensive ( p = 0.02 ; r = 0.68 ), and even more normotensive OSAHS patients ( p < 0.0001 ; r = 0.89 ). Conclusion. nCPAP therapy may have a cardiovascular protective effect in OSAHS patients. hs-CRP level would be useful as a valuable predictor of success in OSAHS treatment monitoring.

The aim of this study was to examine the effect of running exercise modality on oxidative stress. Thirteen endurance athletes (age: 21.46 &plusmn, 0.66 years) performed three different running exercise modalities (Continuous running exercise (CR): continuous running exercise at 75% of VO2max for 25 min, intermittent running exercise #1 (15/15): intermittent running protocol, 15 s running at 75% of VO2max, 15 s passive recovery, performed for 50 min, intermittent running exercise #2 (30/30): intermittent running protocol, 30 s running at 75% of VO2max, 30 s passive recovery, performed for 50 min) in a randomized order. Blood samples were drawn at rest and immediately after each running exercise and assessed for malondialdehyde (MDA), advanced oxidation protein products (AOPP), superoxide dismutase(SOD), and glutathione peroxidase (GPX) activities. MDA increased by 55% following 30/30 exercise (p &lt, 0.01), while it remained unchanged with CR and15/15 exercise. SOD increased after CR (+13.9%, p &lt, 0.05), and also remained unchanged after 15/15 (p &gt, 0.05) and decreased after 30/30 (&minus, 19.7% p &lt, 0.05). GPX and AOPP did not change after exercise in all experimental sessions (p &gt, 0.05). In conclusion, 30/30 intermittent running induced higher lipid damages than the 15/15 and CR exercise. 15/15 intermittent exercise promoted a better balance between free radicals production and antioxidant defense compared to continuous exercise and intermittent 30/30 exercise.

It is well established that intensive physical training induces oxidative stress and muscle damage that can contribute to fatigue and injuries. Melatonin (MEL) has been used as an ergogenic aid (i....

BACKGROUND The present study aimed to investigate the effect of time-of-days (TOD) on some biochemical and hormonal responses after resistance training sessions. METHODS Ten trained subjects (22±2 years) performed, in randomized order, three resistance-training-sessions at 7 a.m., 1 p.m. and 5 p.m. Each training-session included six upper and lower body resistance exercises with 3×10 repetitions. Blood lactate (Lac), creatine kinase (CK), lactate dehydrogenase (LDH), cortisol (C) and testosterone (T) were collected at rest, 3 min and 48 h after each-session. RESULTS At rest, steroidal hormones were higher in the morning compared to the evening (P