Research Abstracts
Almond intake alters the acute plasma dihydroxy-octadecenoic acid (DiHOME) response to eccentric exercise.
Nieman, D.C., A.M. Omar, C.D. Kay, D.M. Kasote, C.A. Sakaguchi, A. Lkhagva, M.M. Weldemariam, Q. Zhang, 2023. Almond intake alters the acute plasma dihydroxy-octadecenoic acid (DiHOME) response to eccentric exercise. Front. Nutr. 9:1042719. https://doi.org/10.3389/fnut.2022.1042719
Introduction: This investigation determined if 4-weeks ingestion of nutrient-dense almonds mitigated post-exercise inflammation and muscle soreness and damage. Methods: An acute 90-min of eccentric exercise (90-EE) was used to induce muscle damage in 64 non-obese adults not engaging in regular resistance training (ages 30-65 years, BMI < 30 kg/m2). Using a parallel group design, participants were randomized to almond (AL) (57 g/d) or cereal bar (CB) (calorie matched) treatment groups for a 4-week period prior to the 90-EE (17 exercises). Blood and 24-h urine samples were collected before and after supplementation, with additional blood samples collected immediately post-90-EE, and then daily during 4 additional days of recovery. Changes in plasma oxylipins, urinary gut-derived phenolics, plasma cytokines, muscle damage biomarkers, mood states, and exercise performance were assessed. Results: The 90-EE protocol induced significant muscle damage, delayed onset of muscle soreness (DOMS), inflammation, reduced strength and power performance, and mood disturbance. Interaction effects (2 group × 7 time points) supported that AL vs. CB was associated with reduced post-exercise fatigue and tension (p = 0.051, 0.033, respectively) and higher levels of leg-back strength (p = 0.029). No group differences were found for post-90-EE increases in DOMS and six cytokines. AL was associated with lower levels of serum creatine kinase immediately- and 1-day post-exercise (p = 0.034 and 0.013, respectively). The 90-EE bout increased plasma levels immediately post-exercise for 13 oxylipins. Interaction effects revealed significantly higher levels for AL vs. CB for 12,13-DiHOME (p < 0.001) and lower levels for 9,10-DiHOME (p < 0.001). Urine levels increased in AL vs. CB for seven gut-derived phenolics including 5-(3′,4′-dihydroxyphenyl)-γ-valerolactone that was inversely related to changes in plasma 9,10-DiHOME (r = -0.029, p = 0.021). Discussion: These data support some positive effects of almond intake in improving mood state, retaining strength, decreasing muscle damage, increasing the generation of gut-derived phenolic metabolites, and altering the plasma oxylipin DiHOME response to unaccustomed eccentric exercise in untrained adults. The elevated post-exercise plasma levels of 12,13-DiHOME with almond intake support positive metabolic outcomes for adults engaging in unaccustomed eccentric exercise bouts.
Keywords: (poly)phenols; almonds; cytokines; exercise; inflammation; metabolites; oxylipins.