Supplementation of Sweet-type Star Fruit Product Controls the Oxidative Stress Status and Enhances the Walking Capacity from Home-Walking Exercise Among Dwelling Elderly in Chiang Mai Province

Abstract

Background: Star fruit (SF) (Averrhoa carambola L.) is seasonal and has special characteristics including a sweet or sour taste. The sweet-type is more available for purchase in many markets in Thailand, when compared to the sour-type. Thus, its antioxidant activity and potentially more modified supplement for elderly health during regular exercise in the community is very challenging. Objective:This study aimed to evaluate the antioxidant activity and physical capacity from supplementation of sweet-type SF among elderly people performing home walking exercise. Methods: The SF product was prepared industrially by mixing SF juice with honey. Its effects on oxidative stress status and physical capacity were studied in a community of elderly people during their walking exercise at home (n=11, 67.00 ± 4.17 years) and compared to a control (n=12, aged 67.50 ± 5.58 years), supplement (n=11, aged 69.63 ± 7.14 years), and walking execise (n =12, aged 67.91 ± 4.33 years). Twenty grams or two teaspoons of supplement in warm water (150 mL) was the guideline for consumption twice daily for 4 weeks, whereas the walking exercise was prescribed with moderate intensity for 30 minutes, 3 days per week. Before and after the 4-week period, the oxidative stress status; glutathione (GSH), ascorbic acid (Vit C), total antioxidant capcity (TAC), and malondialdehyde (MDA), and physical capacity; 6-minute walking distase (6MWD) were evaluated. Results:Results in the four groups showed no statistical difference in any parameters in the baseline period, whereas, a significant difference occurred after the 4-week period. Plasma Vit C and TAC increased and the MDA decreased significantly in the supplement product group, but the GSH and 6MWD were not affected. The GSH and Vit C decreased in the walking exercise group, whereas, its TAC, MDA and 6MWD increased significantly, when compared to baseline. Finally, The GSH and Vit C did not decrease in the combined supplement and walking exercise group, but while their MDA slightly decreased, their TAC and 6MWD increased significantly. Conclusion: Supplementation of the SF product during walking exercise possibly controls oxidative stress status and enhances physical capacity.