Effects of Dietary Nitrate Supplementation on Cardiorespiratory Control in Chronic Heart Failure

Nitrate supplementation: concentrated nitrate-rich beetroot juice (2 x 70 ml/day; approximately 10 mmol nitrate/day; Beet It, James White Drinks, Ipswich, UK) for 8 consecutive days.

Placebo: nitrate-depleted beetroot juice (2 x 70 ml/day; approximately 0.01 mmol nitrate/day; Beet It, James White Drinks, Ipswich, UK) for 8 consecutive days. The placebo juice is similar to the concentrated beetroot juice in appearance, texture, smell and taste and is obtained by removing nitrate ions from the latter.