p-ISSN: 1300-0551
e-ISSN: 2587-1498

Liuba ANDREEVA1, Stanislav TZVETKOV2, Dorothea STEFANOVA1, Lubomir PETROV1, Lazar KAMENOV3, Albert BASSON4, Andy OPOKU4, Trayana DJAROVA4

1National Sports Academy, Department of Physiology and Biochemistry, Sofia, BULGARIA
2National Sports Academy, Department of Sports Medicine Sofia, BULGARIA
3National Sports Academy, Department of Water Sports, Sofia, BULGARIA
4University of Zululand, Department of Biochemistry and Microbiology, SOUTH AFRICA

Anahtar Sözcükler: Esmer çikolata, oksidan stres, kan basıncı; kalp atım hızı, alyuvar, hemoglobin, egzersiz, yüzme

Öz

The aim of this study was to assess the influence of antioxidant rich dark chocolate supplementation on blood pressure (BP), heart rate (HR), red blood cells (RBC), haemoglobin (Hb), and haematocrit (Hct) in response to submaximal exercise in male swimmers. Eleven competitive swimmers aged 18-21 years participated in a randomised experimental protocol consisting of a 10 days washout period with no chocolate intake, and a 10 days supplementation period with daily 50 g dark chocolate ingestion. At the end of each period, two submaximal bicycle ergometer tests (Test І and Test ІІ) of 15 min each (10 min at 60% VO2max, and 5 min at 90% VO2max) were conducted to induce oxidative stress. HR was monitored at baseline, during the tests and following 3 min of recovery. Blood samples were obtained before and following the submaximal tests, and BP was measured at rest and at the end of each period. Significantly lower (p<0.005) systolic and diastolic BP levels were found after 10 days of chocolate intake. HR during Test ІІ was lower and displayed significantly faster decline in the first 3 min of recovery. RBC, Hb and Hct were negligibly lower after performing Test І; whereas slight, but significant increases were observed in these parameters in response to Test ІІ. In conclusion, short-term dark chocolate supplementation may decrease BP and HR levels. It may also modulate beneficial changes in RBC, Hb and Hct in response to submaximal exercise-induced oxidative stress.