https://gala.gre.ac.uk/id/eprint/54629 2026-10-06T11:07:58Z info:eu-repo/semantics/descriptiveMetadata https://gala.gre.ac.uk/id/eprint/54629/ Impact of a short‑term Nitrate and Citrulline co‑supplementation on endurance performance in recreationally trained men and women: a randomized, double‑blind, placebo‑controlled crossover trial Naclerio, Fernando Karsten, Bettina Larumbe-Zabala, Eneko Q Science (General) QP Physiology RC1200 Sports Medicine Dietary nitrate, consumed alone or with citrulline, may enhance endurance performance, but the benefit of co-supplementation in recreationally trained adults remains unclear. This study examined short-term nitrate with and without citrulline for endurance performance and recovery. Twenty-seven adults (17 men, 10 women) completed a randomized, double-blind, placebo-controlled, crossover trial with nitrate (NO₃⁻; 600 mg potassium nitrate, ~9.6 mmol), nitrate + citrulline (NO₃⁻+CIT; same nitrate + 6 g citrulline-malate), and placebo (maltodextrin). Each condition comprised 4 days supplementation and a 72-h washout; supplements were ingested 2.5 h pre-testing. On day 4, participants completed a graded treadmill test (PGT) to determine peak oxygen uptake (V̇O₂peak) and maximal aerobic speed (MAS), followed by an all-out run to exhaustion at MAS (All-Out-T). Lactate was measured pre-/post-PGT, 15-min post-PGT, and post-All-Out-T. Outcomes were analysed using linear mixed-effects models. Compared with PLA, V̇O₂peak increased by 2.6 mL·kg⁻¹·min⁻¹ with NO₃⁻ (95% CI 0.9 to 4.2; 5.4%, p=0.008) and by 4.8 mL·kg⁻¹·min⁻¹ with NO₃⁻+CIT (95% CI 3.1 to 6.4; 10.0%, p=0.001). All-Out-T increased by 48 s with NO₃⁻ (95% CI 21 to 76; 13.3%, p=0.002) and by 100 s with NO₃⁻+CIT (95% CI 73 to 127; 27.4%, p<0.001). NO₃⁻+CIT outperformed NO₃⁻ for MAS and All-Out-T. Treatment influenced post-exercise lactate concentration and lactate removal, whereas lactate measured 15 min after PGT was unchanged. An exploratory analysis suggested possible Treatment × Sex interactions for V̇O₂peak and selected lactate outcomes. In conclusion, short-term nitrate improves endurance performance in recreationally trained adults while adding citrulline provides additional benefits for MAS and time-to-exhaustion. Canadian Science Publishing - National Research Council Canada 2026-10-05 Article PeerReviewed application/pdf en https://gala.gre.ac.uk/id/eprint/54629/7/54629%20NACLERIO_Impact_Of_A_Short%E2%80%91Term_Nitrate_And_Citrulline_Co%E2%80%91Supplementation_%28AAM%29_2026.pdf Naclerio, Fernando, Karsten, Bettina and Larumbe-Zabala, Eneko (2026) Impact of a short‑term Nitrate and Citrulline co‑supplementation on endurance performance in recreationally trained men and women: a randomized, double‑blind, placebo‑controlled crossover trial. Applied Physiology, Nutrition, and Metabolism. ISSN 1715-5312 (Print), 1715-5320 (Online) (In Press) info:eu-repo/semantics/objectFile info:eu-repo/semantics/humanStartPage