Coffee and Oxidative Stress During Exercise in Healthy Humans
Coffee and Oxidative Stress During Exercise in Healthy Humans
Coffee is one of the most widely consumed beverages. It contains polyphenols (chlorogenic acids) and bioavailability of these bioactive compounds is now somewhat well understood. In addition, chlorogenic acids are known to be antioxidants in the cup, but reliable evidence remains to be observed in vivo. The objective of this trial is to understand if regular (14d) coffee intake may be beneficial on biomarkers of oxidative damage measured in urine and plasma after an acute stress caused by exercise.
Coffee is one of the most widely consumed beverages. It contains polyphenols (chlorogenic acids) and bioavailability of these bioactive compounds is now somewhat well understood. However, even if chlorogenic acids are known to be antioxidants in the cup, reliable evidence remains to be observed in vivo.
After medical examination and approval, subjects will undergo 2 periods of 21 days. The first 7 days will consist of a dietary restriction to lower the polyphenols intake. Then subjects will drink at random one of the three treatments for 14 days (4 cups/day). Blood and urine samples will be collected throughout the study to evaluate in vivo effects on oxidative biomarkers. Furthermore, at day 21, subjects will undergo a physical regimen to increase acutely and transiently their oxidative damage. Blood and urine samples collected throughout this challenge will allow us to evaluate the effect of coffee intake in reducing oxidative damage created by exercise compared to placebo.
Inclusion Criteria:
Max oxygen uptake (VO2max, in ml/kg/min) in non athletes Age Males Females 20-29 49 41 30-39 47 39 40-49 45 37
Exclusion Criteria:
Digestive (intestinal, gastric, hepatic or pancreatic), renal or metabolic disease, as determined by the medical (screening) visit and a blood chemistry analysis (glucose, cholesterol, LDL, HDL, triglycerides, aspartate transaminase (ASAT), Alanine transaminase (ALAT), C reactive Protein (CRP), creatinin)
Subjects at cardio-vascular risk rated as intermediate or high (according to the Swiss Society of Cardiology, lipids group (www.agla.ch/p11-1-2.html), meaning those who show at least one of the following criteria:
Abdominal circumference > 102 cm in men, > 88 cm in women Fasting triglycerides ≥ 1.7 mmol/l HDL-cholesterol < 1.0 mmol/l in men, < 1.3 mmol/l in women Systolic arterial blood pressure ≥ 130 mm Hg and/or diastolic arterial blood pressure ≥ 85 mm Hg Plasma glucose ≥ 6.1 mmol/l