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Blood pressure (BP) responses to exercise yield prognostic information beyond resting BP. While habitual higher dietary protein intake is associated with reduced resting BP, few studies have assessed the impact of high-protein meals on acute BP and vasoactive biomarker responses to exercise. To test the hypothesis that consuming a higher-protein, lower fat meal (HP; 30 g protein, 17 g fat, 52 g carbohydrate) would attenuate the BP response to exercise and result in a more robust post-exercise hypotensive response compared to a lower-protein, higher-fat meal (LP; 13 g protein, 25 g fat, 54 g carbohydrate), we recruited 31 pre-hypertensive subjects to complete this randomized, double-blind, cross-over acute feeding study. One hundred sixty-five minutes after consuming the test HP or LP meal, subjects exercised on a cycle ergometer at 70% VO 2 max for 30 minutes. Blood pressure was measured prior to the meal and periodically before, during, and after exercise for a 315-minute period. Blood samples were periodically collected to quantify plasma arginine, arginine metabolites (asymmetric dimethylarginine, symmetric dimethylarginine; ADMA, SDMA), endothelin-1, nitrates, and nitrites in a subset of subjects (n = 15) as shown in Supplemental Table S1. Consuming the HP meal did not influence the BP responses to exercise, including the post-exercise return to baseline BP or systolic BP area under the curve. While the HP meal resulted in greater postprandial plasma arginine concentrations, ADMA, SDMA, endothelin-1, nitrates, and nitrites were unaltered. These results suggest that consuming a higher-protein, lower-fat meal does not influence BP or vasoactive biomarker responses to exercise compared to a lower-protein, higher-fat meal., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Context: A preponderance of evidence supports the beneficial effects of whey protein (WP) supplementation on body composition in men; however, there is currently insufficient evidence to make an equivalent claim in women. Objective: This systematic review and meta-analysis assessed the effects of WP supplementation with or without energy restriction (ER) and resistance training (RT) on changes in body mass, lean mass, and fat mass in women. Data Sources: Pubmed, Scopus, Cochrane, and CINAHL were searched using the keywords "whey protein," "body composition," and "lean mass." Data Extraction: Two researchers independently screened 1845 abstracts and extracted 276 articles. Thirteen randomized controlled trials with 28 groups met the inclusion criteria. Results: Globally, WP supplementation increased lean mass (WMD, 0.37 kg; 95% confidence interval [CI], 0.06 to 0.67) while not influencing changes in fat mass (-0.20 kg; 95%CI, -0.67 to 0.27) relative to non-WP control. The beneficial effect of WP on lean mass was lost when only studies with RT were included in the analysis (n=7 comparisons; 0.23 kg; 95%CI, -0.17 to 0.63). The beneficial effect of WP on lean mass was more robust when only studies with an ER component were included (n=6 comparisons; 0.90 kg; 95%CI, 0.31 to 1.49). There was no effect of WP on lean mass in studies without ER (n=9 comparisons; 0.22 kg; 95%CI, -0.12 to 0.57). Conclusion: Whey protein supplementation improves body composition by modestly increasing lean mass without influencing changes in fat mass. Body composition improvements from WP are more robust when combined with ER . [ABSTRACT FROM AUTHOR]

Context: The impact of timing the consumption of protein supplements in relation to meals on resistance training-induced changes in body composition has not been evaluated systematically. Objective: The aim of this systematic review was to assess the effect of consuming protein supplements with meals, vs between meals, on resistance training-induced body composition changes in adults. Data Sources: Studies published up to 2017 were identified with the PubMed, Scopus, Cochrane, and CINAHL databases. Data Extraction: Two researchers independently screened 2077 abstracts for eligible randomized controlled trials of parallel design that prescribed a protein supplement and measured changes in body composition for a period of 6 weeks or more. Results: In total, 34 randomized controlled trials with 59 intervention groups were included and qualitatively assessed. Of the intervention groups designated as consuming protein supplements with meals (n = 16) vs between meals (n = 43), 56% vs 72% showed an increase in body mass, 94% vs 90% showed an increase in lean mass, 87% vs 59% showed a reduction in fat mass, and 100% vs 84% showed an increase in the ratio of lean mass to fat mass over time, respectively. Conclusions: Concurrently with resistance training, consuming protein supplements with meals, rather than between meals, may more effectively promote weight control and reduce fat mass without influencing improvements in lean mass. [ABSTRACT FROM AUTHOR]