Beetroot Juice Increases Human Muscle Force without Changing Ca2+-Handling Proteins

This study aimed to examine the effects of 7 d of beetroot juice (BRJ) supplementation on SkM contractile characteristics and function. Methods: Recreationally active males (n = 8) underwent transcutaneous electrical muscle stimulation of the vastus lateralis for the evaluation of contractile characteristics before and after 7 d of BRJ supplementation (280 mL·d−1, ~26 mmol NO3−). An additional group of individuals (n = 8) followed the same supplementation protocol but underwent SkM biopsies pre- and post-supplementation for the determination of proteins associated with calcium handling via Western blotting, and the ratio of reduced/oxidized glutathione (GSH:GSSG), an indicator of cellular redox state, via high-performance liquid chromatography (HPLC). Results: After supplementation, there was no change in maximal voluntary force production (602 ± 50 vs 596 ± 56 N) or electrically induced tetanic contractions. By contrast, force production was increased at 10 Hz electrical stimulation (41.1% ± 2.3% vs 37.6% ± 2.4% of peak force, P
Source: Medicine and Science in Sports and Exercise - Category: Sports Medicine Tags: Basic Sciences Source Type: research