Background & aims: Physical activity (PA) breaks may effectively attenuate the detrimental impact of prolonged sitting on acute cognitive performance, perceivable benefits (e.g. mood), vascular function, and metabolic health. To date, the impact of meal composition on the effects of sedentary behavior and/ or PA breaks on health has been scarcely studied. Therefore, our aim was to investigate whether meal composition alters how sedentary behavior and PA breaks affect these acute health outcomes. Methods: A total of 24 overweight and obese, sedentary adults completed four conditions in randomized order in a cross-over design: [a] high-protein, low-fat breakfast (HPLF) þ 4hrs uninterrupted sitting (SIT), [b] HPLF þ 4hrs interrupted sitting (ACT; 5-min cycling every 30 min), [c] Western breakfast (WEST; higher in fats/simple sugars, lower in protein/fiber) þ SIT, [d] WEST þ ACT. WEST and HPLF were isocaloric. Linear mixed models were used to examine changes in cognitive performance (Test of Attentional Performance), perceivable benefits (Likert-scales, Profile of Mood States questionnaire), vascular health (carotid artery reactivity, blood pressure), and metabolic health (post-breakfast glucose, insulin, lipids). Results: Independent of meal composition, we did not observe any effect of PA breaks on cognitive performance, vascular health and post-breakfast lipid responses. PA breaks delayed post-breakfast mood and vigor decrements, as well as increases in fatigue and sleepiness (all p < 0.05), but effects were independent of meal composition (p > 0.05). WEST resulted in higher post-breakfast glucose levels compared to HPLF (p < 0.05), while PA breaks did not impact this response (p > 0.05). PA breaks reduced post-breakfast insulin (p < 0.05), which did not differ between meals (p > 0.05). Conclusions: The acute impact of PA breaks and/or prolonged sitting on cognitive performance, perceivable benefits, and vascular and metabolic health was not altered by the composition of a single meal in overweight/obese, sedentary adults. Possibly, breaking up prolonged sitting, rather than meal composition, is a more potent strategy to impact acute health outcomes, such as perceivable benefits and insulin levels.

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The regulation of blood flow to peripheral muscles is crucial for proper skeletal muscle functioning and exercise performance. During exercise, increased mitochondrial oxidative phosphorylation leads to increased electron leakage and consequently induces an increase in ROS formation, contributing to DNA, lipid, and protein damage. Moreover, exercise may increase blood- and intramuscular inflammatory factors leading to a deterioration in endurance performance. The aim of this review is to investigate the potential mechanisms through which the polyphenol hesperidin could lead to enhanced exercise performance, namely improved endothelial function, reduced exercise-induced oxidative stress, and inflammation. We selected in vivo RCTs, animal studies, and in vitro studies in which hesperidin, its aglycone form hesperetin, hesperetin-metabolites, or orange juice are supplemented at any dosage and where the parameters related to endothelial function, oxidative stress, and/or inflammation have been measured. The results collected in this review show that hesperidin improves endothelial function (via increased NO availability), inhibits ROS production, decreases production and plasma levels of pro-inflammatory markers, and improves anaerobic exercise outcomes (e.g., power, speed, energy). For elite and recreational athletes, hesperidin could be used as an ergogenic aid to enhance muscle recovery between training sessions, optimize oxygen and nutrient supplies to the muscles, and improve anaerobic performance.

Objectives This study investigates whether a citrus and pomegranate complex (CPC) improves physical fitness, mental well-being, and blood biomarkers for oxidative stress and endothelial function in healthy elderly. Design A randomized placebo-controlled cross-over trial. Participants The study included 36 healthy elderly aged 60–75 years old. Intervention and Measurements Participants received four weeks of CPC supplementation and performed the handgrip strength and senior fitness test. Quality of life (QOL) was assessed and blood samples were analyzed for oxidative stress and endothelial function markers. Results After four weeks of CPC supplementation, handgrip strength significantly improved (p=0.019), compared to placebo. Moreover, the thinking, memory, learning, and concentration facets were improved (p=0.042), compared to placebo, and plasma malondialdehyde decreased, compared to placebo (p=0.033). The intervention did not affect senior fitness and the other QOL domains and blood parameters. Conclusion Four weeks of daily CPC supplementation significantly improves handgrip strength and self-evaluated measures of psychological function in healthy older adults. Further research should focus on mechanisms associated with physical performance.