The Impact of a Natural Olive-Derived Phytocomplex (OliPhenolia®) on Exercise-Induced Oxidative Stress in Healthy Adults

Abstract

The role of natural polyphenols in reducing oxidative stress and/or supporting antioxidant mechanisms, particularly relating to exercise, is of high interest. The aim of this study was to investigate OliPhenolia® (OliP), a biodynamic and organic olive fruit water phytocomplex, rich in hydroxytyrosol (HT), for the first time within an exercise domain. HT bioavailability from OliP was assessed in fifteen healthy volunteers in a randomized, double-blind, placebo controlled cross-over design (age: 30 ± 2 yrs; body mass: 76.7 ± 3.9 kg; height: 1.77 ± 0.02 m), followed by a separate randomized, double-blinded, cohort trial investigating the short-term impact of OliP consumption (2 × 28 mL∙d−1 of OliP or placebo (PL) for 16-days) on markers of oxidative stress in twenty-nine recreationally active participants (42 ± 2 yrs; 71.1 ± 2.1 kg; 1.76 ± 0.02 m). In response to a single 28 mL OliP bolus, plasma HT peaked at 1 h (38.31 ± 4.76 ng∙mL−1), remaining significantly elevated (p < 0.001) until 4 h. Plasma malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH) and HT were assessed at rest and immediately following exercise (50 min at ~75% VO2max then 10 min intermittent efforts) and at 1 and 24 h post-exercise, before and after the 16-day supplementation protocol. Plasma HT under resting conditions was not detected pre-intervention, but increased to 6.3 ± 1.6 ng·mL−1 following OliP only (p < 0.001). OliP demonstrated modest antioxidant effects based on reduced SOD activity post-exercise (p = 0.016) and at 24 h (p ≤ 0.046), and increased GSH immediately post-exercise (p = 0.009) compared with PL. No differences were reported for MDA and CAT activity in response to the exercise protocol between conditions. The phenolic compounds within OliP, including HT, may have specific antioxidant benefits supporting acute exercise recovery. Further research is warranted to explore the impact of OliP following longer-term exercise training, and clinical domains pertinent to reduced oxidative stress.

The Effect of a Hydroxytyrosol-Rich, Olive-Derived Phytocomplex on Aerobic Exercise and Acute Recovery

“…Participants were provided with a personal login and guidance instructions to support detailed dietary tracking. Participants were required to record consumption of all food items and liquids for 3-days leading into each exercise test as part of this study, as well as across the 16-day intervention period [ 45 ] and were checked regularly by the same researcher for consistency throughout the intervention. A list of polyphenol-rich ‘foods to avoid’ was also provided for participants to adhere to in the 3-days leading into each laboratory visit (see Supplementary Materials, Table S1 ).…”

“…Participants were requested to maintain habitual lifestyle and exercise patterns across the study, ensuring consistency across the 16-day period throughout the course of supplementation. Session type, mean session heart rate, exercise duration and perceived session exertion (using a standard 0–10 visual analogue scale) were recorded following the completion of each training session as reported elsewhere [ 45 ].…”

“…Visit 2 and 4 involved 65 min of exercise, with an overall target exercise intensity of ~75% O 2max , designed to elicit muscular oxidative stress [ 45 ]. Participants completed a 5 min warm-up at a speed corresponding to LT1.…”

“…Exercise intensity was consistent between visit 2 and 4. Additionally, as a means to quantify whether the nutritional intervention influenced plasma HT (as the main polyphenol in OliP), resting whole blood measures were undertaken prior to both visit 2 and 4 (as part of a larger study reported elsewhere [ 45 ]). For this, whole blood samples were collected into 4 mL Vacuette™ K2EDTA tubes (Greiner Bio-One GmbH, Kremsmunster, Austria), centrifuged at 2000 rcf for 10 min, with extracted plasma stored at −80 °C until analysis for HT.…”

“…For this, whole blood samples were collected into 4 mL Vacuette™ K2EDTA tubes (Greiner Bio-One GmbH, Kremsmunster, Austria), centrifuged at 2000 rcf for 10 min, with extracted plasma stored at −80 °C until analysis for HT. Plasma HT was assessed using a liquid–liquid extraction method following acidic hydrolysis, with gas chromatography–mass spectrometry (GC-MS) analysis (Agilent 7820A GC, Santa Clara, CA, USA [ 45 ]).…”