Redox and autonomic responses to acute exercise-post recovery following Opuntia ficus-indica juice intake in physically active women

Abstract

Background: The aim of this study was to investigate if the supplementation with Opuntia ficus-indica (OFI) juice may affect plasma redox balance and heart rate variability (HRV) parameters following a maximal effort test, in young physically active women.

Methods: A randomized, double blind, placebo controlled and crossover study comprising eight women (23.25 ± 2.95 years, 54.13 ± 9.05 kg, 157.75 ± 0.66 cm and BMI of 21.69 ± 0.66 kg/m2) was carried out. A juice containing OFI diluted in water and a Placebo solution were supplied (170 ml; OFI = 50 ml of OFI juice + 120 ml of water; Placebo = 170 ml beverage without Vitamin C and indicaxanthin). Participants consumed the OFI juice or Placebo beverage every day for 3 days, before performing a maximal cycle ergometer test, and for 2 consecutive days after the test. Plasma hydroperoxides and total antioxidant capacity (PAT), Skin Carotenoid Score (SCS) and HRV variables (LF, HF, LF/HF and rMSSD) were recorded at different time points.

Results: The OFI group showed significantly lower levels of hydroperoxides compared to the Placebo group in pre-test, post-test and 48-h post-test. PAT values of the OFI group significantly increased compared to those of the Placebo group in pre-test and 48-h post-test. SCS did not differ between groups. LF was significantly lower in the OFI group 24-h after the end of the test, whereas rMSSD was significantly higher in the OFI group 48-h post-test.

Conclusion: OFI supplementation decreased the oxidative stress induced by intense exercise and improved autonomic balance in physically active women.

Keywords: Autonomic nervous system; Cactus pear juice supplementation; High frequency; Hydroperoxides; Low frequency; Oxidative stress; Redox balance; Total antioxidant capacity.

Fig. 1

Study design. The subjects were randomly divided into 2 groups and randomly assigned to either a supplementation of 50 ml of concentred peeled fresh fruit juice of Sicilian OFI, which was diluted to 170 ml with water, or 170 ml of Placebo (PL), for 5 days. One week before starting the supplementation, each participant performed the first maximal effort test (BL). The participants consumed OFI or Placebo for 3 days before the second maximal effort test and continued to take it for 2 consecutive days after the testing procedure. After a 2 week wash out period, the treatments were reversed

Fig. 2

Changes in plasma hydroperoxide levels in response to OFI or PL supplementation before and immediately, 24 h and 48 h after a maximal effort test. *p < 0.05 OFI pre-, post- and 48 h post-test vs. corresponding PL groups; #p < 0.05 OFI pre-test vs post-test and 24 h post-test; §p < 0.05 OFI 24 h post-test vs 48 h post-test

Fig. 3

Measurement of plasma antioxidant capacity following OFI or PL supplementation before,immediately after, 24 h and 48 h after a maximal effort test. *p < 0.05 OFI pre- and 48 h post-test vs corresponding PL groups; #p < 0.05 OFI pre-test vs post-test and 24 h post-test; §p < 0.05 OFI post-test vs 48 h post-test; ˆp < 0.05 OFI 24 h post-test vs 48 h post-test

Fig. 4

Variations in Skin Carotenoid Score based on the Resonance Raman Spectroscopy following OFI or PL supplementation before, immediately after, 24 h and 48 h after a maximal effort test. §p < 0.05 OFI post-test vs 24 h-post-test and 48 h post-test