PURPOSE:This study tested the effectiveness of a fruit, berry, and vegetable concentrate (FVC), Juice Plus+® (NSA LLC, Collierville, TN), supplement on muscle function and oxidative stress in response to an acute bout of eccentric exercise (EE).

METHODS:Forty-one healthy volunteers (age = 18-35 yr) were randomly assigned to either a placebo (P) or an FVC treatment taking capsules for 28 d (6 d(-1)) before EE and for the next 4 d. All subjects completed four sets of 12 repetitions of eccentric elbow flexion with their nondominant arm. Blood, muscle soreness (MS), range of motion (ROM), and maximal isometric force (MIF) of the elbow flexors were obtained before and immediately after exercise and at 2, 6, 24, 48, and 72 h postexercise. Plasma was analyzed for creatine kinase (CK), lipid hydroperoxides, malondialdehyde (MDA), and protein carbonyls (PC). Glutathione ratio was determined from whole-blood extracts.

RESULTS:MS, ROM, MIF, and plasma CK demonstrated significant time effects independent of treatment. MS and plasma CK increased over time, whereas ROM and MIF decreased over time. There was a significant time and time× treatment effect for plasma PC and MDA. PC and MDA increased over time in the P group (P<0.01) but were not significantly altered in the FVC-treated group at any time. No significant changes were noted in lipid hydroperoxides. The glutathione ratio was elevated immediately postexercise in both groups (P<0.01) and elevated 6 h postexercise with P compared with the FVC-treated group (P<0.05).

CONCLUSION:This study reports that 4 wk of pretreatment with an FVC can attenuate blood oxidative stress markers induced by EE but had no significant impact on the functional changes related to pain and muscle damage.

PURPOSE:The aim of the present study was to investigate the effects of the consumption of two cloudy apple juices with different polyphenol and vitamin C contents on antioxidant status, cardiometabolic and inflammation markers in healthy young adults.

METHODS:Twenty subjects, aged 21-29 years, completed a randomized crossover study. At each 4-week intervention period, the volunteers randomly consumed two glasses (2× 250 mL/day) of either a vitamin C-rich apple juice (VCR) (60 mg/L vitamin C and 510 mg catechin equivalent/L) or a polyphenol-rich (PR) juice (22 mg/L vitamin C and 993 mg catechin equivalent/L). Blood and urine samples were collected throughout the study, and markers of antioxidant status, glucose metabolism, lipid profile and inflammation were measured.

RESULTS:The comparison of the post-intervention minus pre-intervention change revealed differential results in HOMA index, total cholesterol, ICAM-1 and VCAM-1 (P<0.05) across juices. During the VCR period, plasma antioxidant activity (FRAP) increased (P = 0.031), while ICAM-1 and total cholesterol showed a trend to decrease (P = 0.060 and P = 0.094, respectively). During the PR period, plasma insulin and HOMA increased, and total glutathione decreased (P<0.05).

CONCLUSIONS:A joint consumption of apple juice natural antioxidants such as vitamin C and polyphenols might provide mild favorable effects on cardiometabolic markers, as compared to apple polyphenols alone.