Chronic obstructive pulmonary disease (COPD) results in exercise intolerance. Dietary nitrate supplementation has been shown to lower blood pressure (BP), reduce the oxygen cost of exercise, and enhance exercise tolerance in healthy volunteers. This study assessed the effects of dietary nitrate on the oxygen cost of cycling, walking performance and BP in individuals with mild-moderate COPD. Thirteen patients with mild-moderate COPD were recruited. Participants consumed 70 ml of either nitrate-rich (6.77 mmol nitrate; beetroot juice) or nitrate-depleted beetroot juice (0.002 mmol nitrate; placebo) twice a day for 2.5 days, with the final supplement ~3 hours before testing. BP was measured before completing two bouts of moderate-intensity cycling, where pulmonary gas exchange was measured throughout. The six-minute walk test (6 MWT) was completed 30 minutes subsequent to the second cycling bout. Plasma nitrate concentration was significantly elevated following beetroot juice vs. placebo (placebo; 48 ± 86 vs. beetroot juice; 215 ± 84 µM, P = 0.002). No significant differences were observed between placebo vs. beetroot juice for oxygen cost of exercise (933 ± 323 vs. 939 ± 302 ml: min(-1); P = 0.88), distance covered in the 6 MWT (456 ± 86 vs. 449 ± 79 m; P = 0.37), systolic BP (123 ± 14 vs. 123 ± 14 mmHg; P = 0.91), or diastolic BP (77 ± 9 vs. 79 ± 9 mmHg; P = 0.27). Despite a large rise in plasma nitrate concentration, two days of nitrate supplementation did not reduce the oxygen cost of moderate intensity cycling, increase distance covered in the 6 MWT, or lower BP.

Dietary nitrate supplementation has been shown to reduce the oxygen (O2) cost of exercise and enhance exercise tolerance in healthy individuals. This study assessed whether similar effects could be observed in individuals with type 2 diabetes (T2DM). In a randomized, double-blind, placebo-controlled crossover study, 48 participants with T2DM supplemented their diet for 4 days with either nitrate-rich beetroot juice (70ml/day, 6.43mmol nitrate/day) or nitrate-depleted beetroot juice as placebo (70ml/day, 0.07mmol nitrate/day). After each intervention period, resting plasma nitrate and nitrite concentrations were measured subsequent to participants completing moderate-paced walking. Pulmonary gas exchange was measured to assess the O2 cost of walking. After a rest period, participants performed the 6-min walk test (6MWT). Relative to placebo, beetroot juice resulted in a significant increase in plasma nitrate (placebo, 57±66 vs beetroot, 319±110µM; P < 0.001) and plasma nitrite concentration (placebo, 680±256 vs beetroot, 1065±607nM; P < 0.001). There were no differences between placebo juice and beetroot juice for the O2 cost of walking (946±221 vs 939±223ml/min, respectively; P = 0.59) and distance covered in the 6MWT (550±83 vs 554±90m, respectively; P = 0.17). Nitrate supplementation did not affect the O2 cost of moderate-paced walking or improve performance in the 6MWT. These findings indicate that dietary nitrate supplementation does not modulate the response to exercise in individuals with T2DM.

Oxidative stress may play an important role in the pathophysiology of cystic fibrosis (CF). This review aimed to quantify CF-related redox imbalances. Systematic searches of the Medline, CINAHL, CENTRAL and PsycINFO databases were conducted. Mean content of blood biomarkers from people with clinically-stable CF and non-CF controls were used to calculate the standardized mean difference (SMD) and 95% confidence intervals (95% CI). Forty-nine studies were eligible for this review including a total of 1792 people with CF and 1675 controls. Meta-analysis revealed that protein carbonyls (SMD: 1.13, 95% CI: 0.48 to 1.77), total F₂-isoprostane 8-iso-prostaglandin F_2α (SMD: 0.64, 95% CI: 0.23 to 1.05) and malondialdehyde (SMD: 1.34, 95% CI: 0.30 to 2.39) were significantly higher, and vitamins A (SMD: -0.66, 95% CI -1.14 to -0.17) and E (SMD: -0.74, 95% CI: -1.28 to -0.20), β-carotene (SMD: -1.80, 95% CI: -2.92 to -0.67), lutein (SMD: -1.52, 95% CI: -1.83 to -1.20) and albumin (SMD: -0.98, 95% CI: -1.68 to -0.27) were significantly lower in the plasma or serum of people with CF versus controls. This systematic review and meta-analysis found good evidence for reduced antioxidant capacity and elevated oxidative stress in people with clinically-stable CF.

Objectives To assess acceptability and feasibility of trial processes and the Rehabilitation Training (ReTrain) intervention including an assessment of intervention fidelity. Design A two-group, assessor-blinded, randomised controlled trial with parallel mixed methods process and economic evaluations. Setting Community settings across two sites in Devon. Participants Eligible participants were: 18 years old or over, with a diagnosis of stroke and with self-reported mobility issues, no contraindications to physical activity, discharged from National Health Service or any other formal rehabilitation programme at least 1 month before, willing to be randomised to either control or ReTrain and attend the training venue, possessing cognitive capacity and communication ability sufficient to participate. Participants were individually randomised (1:1) via a computer-generated randomisation sequence minimised for time since stroke and level of functional disability. Only outcome assessors independent of the research team were blinded to group allocation. Interventions ReTrain comprised (1) an introductory one-to-one session; (2) ten, twice-weekly group classes with up to two trainers and eight clients; (3) a closing one-to-one session, followed by three drop-in sessions over the subsequent 3 months. Participants received a bespoke home-based training programme. All participants received treatment as usual. The control group received an exercise after stroke advice booklet. Outcome measures Candidate primary outcomes included functional mobility and physical activity. Results Forty-five participants were randomised (ReTrain=23; Control=22); data were available from 40 participants at 6 months of follow-up (ReTrain=21; Control=19) and 41 at 9 months of follow-up (ReTrain=21; Control=20). We demonstrated ability to recruit and retain participants. Participants were not burdened by the requirements of the study. We were able to calculate sample estimates for candidate primary outcomes and test procedures for process and health economic evaluations. Conclusions All objectives were fulfilled and indicated that a definitive trial of ReTrain is feasible and acceptable. Trial registration number NCT02429180; Results.

Raynaud’s phenomenon (RP) is characterized by recurrent transient peripheral vasospasm and lower nitric oxide (NO) bioavailability in the cold. We investigated the effect of nitrate-rich beetroot juice (BJ) supplementation on 1) NO-mediated vasodilation, 2) cutaneous vascular conductance (CVC) and skin temperature (T_sk) following local cooling, and 3) systemic anti-inflammatory status. Following baseline testing, 23 individuals with RP attended four times, in a double-blind, randomized crossover design, following acute and chronic (14 days) BJ and nitrate-depleted beetroot juice (NDBJ) supplementation. Peripheral T_skand CVC were measured during and after mild hand and foot cooling, and during transdermal delivery of acetylcholine and sodium nitroprusside. Markers of anti-inflammatory status were also measured. Plasma nitrite concentration ([nitrite]) was increased in the BJ conditions ( P < 0.001). Compared with the baseline visit, thumb CVC was greater following chronic-BJ (Δ2.0 flux/mmHg, P = 0.02) and chronic-NDBJ (Δ1.45 flux/mmHg, P = 0.01) supplementation; however, no changes in T_skwere observed ( P > 0.05). Plasma [interleukin-10] was greater, pan endothelin and systolic and diastolic blood pressure (BP) were reduced, and forearm endothelial function was improved, by both BJ and NDBJ supplementation ( P < 0.05). Acute and chronic BJ and NDBJ supplementation improved anti-inflammatory status, endothelial function and blood pressure (BP). CVC following cooling increased post chronic-BJ and chronic-NDBJ supplementation, but no effect on T_skwas observed. The key findings are that beetroot supplementation improves thumb blood flow, improves endothelial function and anti-inflammatory status, and reduces BP in people with Raynaud’s.NEW & NOTEWORTHY This is the first study to examine the effect of dietary nitrate supplementation in individuals with Raynaud’s phenomenon. The principal novel findings from this study were that both beetroot juice and nitrate-depleted beetroot juice 1) increased blood flow in the thumb following a cold challenge; 2) enhanced endothelium-dependent and -independent vasodilation in the forearm; 3) reduced systolic and diastolic blood pressure, and pan-endothelin concentration; and 4) improved inflammatory status in comparison to baseline.

Early in the coronavirus-2019 (COVID-19) containment strategy, people with end-stage renal disease (ESRD) were identified as extremely clinically vulnerable and subsequently asked to ‘shield’ at home where possible. The aim of this study was to investigate how these restrictions and the transition to an increased reliance on telemedicine within clinical care of people living with kidney disease impacted the physical activity (PA), wellbeing and quality of life (QoL) of adults dialysing at home (HHD) or receiving in-centre haemodialysis (ICHD) in the UK. Individual semistructured telephone interviews were conducted with adults receiving HHD (n = 10) or ICHD (n = 10), were transcribed verbatim and, subsequently, thematically analysed. As result of the COVID-19 restrictions, PA, wellbeing and QoL of people with ESRD were found to have been hindered. However, widespread support for the continued use of telemedicine was strongly advocated and promoted independence and satisfaction in patient care. These findings highlight the need for more proactive care of people with ESRD if asked to shield again, as well as increased awareness of safe and appropriate PA resources to help with home-based PA and emotional wellbeing.