Want to improve your muscle force during exercise? Drink beetroot juice. Beetroot juice contains dietary nitrate which is known to boost endurance and enhance high-intensity exercise. Researchers at the University of Exeter and the US National Institutes of Health investigated this positive effect. They found that after giving participants dietary nitrate, “this nitrate boost caused an increase in muscle force of seven per cent, compared to when the participants took a placebo.” Test the theory for yourself. 1 hour before exercising, drink fresh-pressed beetroot juice.