L-Citrulline Supplementation Improves Arterial Blood Flow and Muscle Oxygenation during Handgrip Exercise in Hypertensive Postmenopausal Women.
- 2024-06-19
- Nutrients 16(12)
- Yejin Kang
- Katherine N Dillon
- Mauricio A Martinez
- Arun Maharaj
- Stephen M Fischer
- Arturo Figueroa
- PubMed: 38931289
- DOI: 10.3390/nu16121935
Study Design
- Type
- Randomized Controlled Trial (RCT)
- Population
- 22 hypertensive postmenopausal women
- Methods
- Compared to the placebo, CIT significantly increased FMD and reduced aortic systolic BP at rest and improved exercise BF, VC, TSI, and HHb
- Blinding
- Double-blind
- Duration
- 4 weeks
- Funding
- Unclear
- Rigorous Journal
Endothelial dysfunction decreases exercise limb blood flow (BF) and muscle oxygenation. Acute L-Citrulline supplementation (CIT) improves muscle tissue oxygen saturation index (TSI) and deoxygenated hemoglobin (HHb) during exercise. Although CIT improves endothelial function (flow-mediated dilation [FMD]) in hypertensive women, the impact of CIT on exercise BF and muscle oxygenation (TSI) and extraction (HHb) are unknown. We examined the effects of CIT (10 g/day) and a placebo for 4 weeks on blood pressure (BP), arterial vasodilation (FMD, BF, and vascular conductance [VC]), and forearm muscle oxygenation (TSI and HHb) at rest and during exercise in 22 hypertensive postmenopausal women. Compared to the placebo, CIT significantly (p < 0.05) increased FMD (Δ-0.7 ± 0.6% vs. Δ1.6 ± 0.7%) and reduced aortic systolic BP (Δ3 ± 5 vs. Δ-4 ± 6 mmHg) at rest and improved exercise BF (Δ17 ± 12 vs. Δ48 ± 16 mL/min), VC (Δ-21 ± 9 vs. Δ41 ± 14 mL/mmHg/min), TSI (Δ-0.84 ± 0.58% vs. Δ1.61 ± 0.46%), and HHb (Δ1.03 ± 0.69 vs. Δ-2.76 ± 0.77 μM). Exercise BF and VC were positively correlated with improved FMD and TSI during exercise (all p < 0.05). CIT improved exercise artery vasodilation and muscle oxygenation via increased endothelial function in hypertensive postmenopausal women.
Research Insights
improved exercise BF (Δ17 ± 12 vs. Δ48 ± 16 mL/min)
- Effect
- Beneficial
- Effect size
- Moderate
- Dose
- 10 g/day
Compared to the placebo, CIT significantly (p < 0.05) increased FMD (Δ-0.7 ± 0.6% vs. Δ1.6 ± 0.7%)
- Effect
- Beneficial
- Effect size
- Large
- Dose
- 10 g/day
TSI (Δ-0.84 ± 0.58% vs. Δ1.61 ± 0.46%)
- Effect
- Beneficial
- Effect size
- Large
- Dose
- 10 g/day
VC (Δ-21 ± 9 vs. Δ41 ± 14 mL/mmHg/min)
- Effect
- Beneficial
- Effect size
- Moderate
- Dose
- 10 g/day
reduced aortic systolic BP (Δ3 ± 5 vs. Δ-4 ± 6 mmHg) at rest
- Effect
- Beneficial
- Effect size
- Moderate
- Dose
- 10 g/day
HHb (Δ1.03 ± 0.69 vs. Δ-2.76 ± 0.77 μM)
- Effect
- Beneficial
- Effect size
- Moderate
- Dose
- 10 g/day