The effects of a (poly)phenol-rich food intervention on markers of exercise-induced inflammation and oxidative stress: A randomised controlled trial

Abrar Al Hebshi; Josh Thorley; Ana Rodriguez-Mateos; Zicheng Zhang; Lewis J James; Tom Clifford

doi:10.1113/EP093383

The effects of a (poly)phenol-rich food intervention on markers of exercise-induced inflammation and oxidative stress: A randomised controlled trial

Exp Physiol. 2026 Jan 23. doi: 10.1113/EP093383. Online ahead of print.

Authors

Abrar Al Hebshi^{1

2}, Josh Thorley³, Ana Rodriguez-Mateos⁴, Zicheng Zhang⁴, Lewis J James^{2

5}, Tom Clifford²

Affiliations

¹ Department of Clinical Nutrition, Faculty of Applied Medical Sciences, Umm Al-Qura University, Makkah, Saudi Arabia.
² School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK.
³ School of Medicine, University of Nottingham, Nottingham, UK.
⁴ Department of Nutritional Sciences, School of Life Course and Population Sciences, King's College London, London, UK.
⁵ NIHR Leicester Biomedical Research Centre, University Hospitals of Leicester NHS Trust and the University of Leicester, Leicester, UK.

PMID: 41578624
DOI: 10.1113/EP093383

Abstract

This study examined whether consuming a (poly)phenol-rich food before strenuous muscle-damaging exercise can modify post-exercise markers of inflammation and oxidative stress. Using a double-blinded, randomised, placebo-controlled, between-subjects design, 26 recreationally active males (n = 15) and females (n = 11) consumed higher-(poly)phenol (H-POL) foods (dates, dark chocolate, pomegranate; 285.1 mg/day) or lower-(poly)phenol foods (L-POL) (cereal bar, milk chocolate, sports drink; 88.3 mg/day) for 3 days before, and then 30 min before, strenuous exercise (100 drop jumps, 50 squat jumps). A range of blood markers associated with inflammation (total and differential leukocytes, interleukin (IL)-6, IL-10, IL-1β, IL-2, IL-4, IL-12, tumour necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), monocyte chemoattractant protein-1 (MCP-1), granulocyte colony-stimulating factor), and oxidative stress (glutathione peroxidase (GPX), 4-hydroxynonenal (4-HNE), and urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG)) were quantified pre, immediately post, 1 and 2 h post-exercise. One hundred and nineteen plasma (poly)phenol metabolites were measured pre, immediately post and 1 h post-exercise. Total plasma (poly)phenol concentrations were greater in the H-POL vs. L-POL intervention, peaking 1 h post-exercise (H-POL: 239.5 ± 87.8 µM vs. L-POL 58.9 ± 33.8 µM; P < 0.001). There were interaction effects for IL-10 and TNF-α but no differences with post hoc tests. Urinary 8-OHdG excretion was higher in H-POL vs L-POL (condition effect; P < 0.001), whereas erythrocytes GPX activity was higher in the L-POL vs. H-POL (condition effect; P < 0.001). A (poly)phenol food intervention before exercise increased total plasma (poly)phenol concentrations but had limited and inconsistent effects on markers of inflammation and oxidative stress in the 2 h after strenuous exercise.

Keywords: exercise recovery; nutraceuticals; oxidative stress; phytochemicals.