The effect of single-dose beetroot juice on the blood pressure and cognition of healthy older versus younger adult

INTERVENTION: Beetroot intervention: One bottle (150ml) of nitrate‐rich beetroot juice (10.5 mmol nitrate) consumed acutely 2.25 hours prior to repeating testing and 2.5 hr prior to 30 minutes of walking exercise at moderate intensity (defined as a 3 on the Borg RPE 10‐point scale). Intervention adherence will be controlled for by observing participants consume the drink in the laboratory Wash out period between trial was one week CONDITION: Cognitive decline High Blood Pressure PRIMARY OUTCOME: Change in blood pressure (Average of three resting blood pressure measures using an OMRON automatic blood pressure machine) Plasma nitrate concentrations (via blood sample analysis with HPLC) Plasma nitrite concentrations (via blood sample analysis with HPLC) SECONDARY OUTCOME: Cardiovascular performance (from oxygen uptake measured using Douglas bags) Cognitive performance (via three cognitive tests; choice reaction test, rapid visual information processing test and Stroop test); this was a composite secondary outcome Mood and perception (using feeling scale, felt arousal scale, profile of mood states, and rating of perceived exertion scale); this was a composite secondary outcome INCLUSION CRITERIA: Between the ages of 18 ‐ 30y or 50 ‐ 70y Able to walk at moderate intensity for 30 min Healthy individuals