Beetroot, Nitrate And Nitric Oxide

Question 1

What did Heiss et al (2012) find??

Answer 1

Nitrates have an impact on vasodilation - FMD was significantly higher for nitrate group compared to water in an acute setting (1.5h)

Question 2

What did Hobbs et al (2013) find??

Answer 2

Found increased nitrate led to decreases in SBP over an acute timeframe (1.5h)

Question 3

Discuss the key nitrate literature (Bailey et al, 2009)?? When giving 5.6mM/day of nitrate compared to placebo.

Answer 3

Looked at ergogenic effects of dietary nitrate supplementation.
Saw an increase in the utilisation of the finite anaerobic reserves , and an accumulation of fatigue - related metabolites in nitrate group.
Successfully showed nitrate reduced the oxygen cost of sub-maximal exercise.
Also showed nitrate supplementation improves ex tolerance (16% increase in TTE).

Question 4

What did Lansley et al (2011) find??

Answer 4

Looked at the ergogenic effects of dietary nitrate on athletes performance.
Showed that during both a 4km TT and 16km TT, nitrate supplementation has the potential to benefit athletic performance , at least in events of ~5-30 mins in duration .
Beetroot supplementation reduced:- o2 consumption during mod intensity ex (⬆️efficiency), and the Vo2 slow component during high intensity exercise (indicating reduced utilisation of Pcr/accumulation of fatigue related metabolites).

Question 5

Discuss Bailey et al (2010) when he looked at the mechanisms of nitrate action??

Answer 5

Found using P-MRS that 6 day nitrate supplementation (beetroot) blunts the decrease in phosphocreatine in muscle when performing leg ext exercise.
Also showed significantly less ATP turnover in total, when supplemented with nitrate.

These results mean more efficient muscle action (due to reduced cross-bridge cycling / reduced actomyosin ATPase activity and reduced calcium ATPase activity)

Question 6

Discuss Larsen et al (2011)??

Answer 6

Shown that beetroot juice supplementation improves mitochondrial efficiency in humans

Question 7

Discuss Richards et al (2018)??

Answer 7

Looked at nitrate and exercising limb blood flow in an acute setting (2-3h intervention) followed by a hand grip task at various MVC.
- showed significant increases in forearm blood flow and vasodilation

Question 8

Discuss the papers of Schroeter et al (2006) and Taubert et al (2003) looking at cocoa intake???

Answer 8

Schroeter et al - showed cocoa intake improves vascular function in humans, by demonstrating a higher FMD, plasma NO, and plasma flavanol levels

Taubert et al (2003) showed that cocoa flavanols decrease BP (both SBP and DBP)