The effect of Opuntia ficus‐indica juice supplementation on oxidative stress, cardiovascular parameters, and biochemical markers following yo‐yo Intermittent recovery test

The aim of the study was to investigate the effect of a flavonoid‐rich fresh fruit juice on cardiovascular, oxidative stress, and biochemical parameters during the yo‐yo intermittent recovery test (YYIRT). Twenty‐two healthy males subjects participated in this study divided into two groups: An experimental group (EG: n = 11) who consumed the antioxidant supplement and a control group (CG: n = 11). All participants performed two test sessions at 07:00 hr before and after 2 weeks of supplementation with Opuntia ficus‐indica juice. Blood samples were taken before (P1) and immediately (P2) after the YYIRT. Our results showed that following the 2,2‐diphenyl‐1‐ picrylhydrazyl (DPPH●) test, the Opuntia ficus‐indica juice has an antioxidant capacity for capturing free radicals (p < .05) and reducing oxidative stress related to exercise. Concerning biochemical and cardiovascular parameters, our results showed a significant increase on total cholesterol (TC) (p < .01), triglycerides (TG) (p < .05), high‐density lipoprotein (HDL) (p < .01), low‐density lipoprotein (LDL) (p < .01), creatine kinase (CK) (p < .01), lactate deshydrogenase (LDH) (p < .01), glucose (GLC) (p < .01), systolic (SBP), and diastolic blood pressure (DBP) (p < .01) immediately after exercise. However, TC (p < .05), TG (p < .05) and LDL (p < .05), the maximal heart rate (HRmax), the CK (p < .05), and LDH (p < .01) as well as the malondialdehyde (MDA) (p < .01) demonstrated a significant decrease after supplementation of Opuntia ficus‐indica juice before and immediately after YYIRT. However, no significant effect on HDL (p > .05), GLC (p > .05) levels nor the SBP and DBP (p > .05) was observed after supplementation with Opuntia ficus‐indica juice. The supplementation leads to an improvement on YYIRT performance (The total distance covered during the YYIRT, VO2max, VMA) and the rating of perceived exertion (RPE). Opuntia ficus‐indica juice has a potent antioxidant activity that reduces total and LDL‐cholesterol with only a moderate lowering of HDL‐cholesterol and oxidative stress. Moreover, supplementation decreases muscle damage caused by the endurance exercise