1/ Pak choi
It’s high in iron and is packed with vitamins A, C and K. It also contains antioxidant minerals, such as manganese and zinc.
Eat: In stir-fries.
2/ Peppermint oil
Research published in the Journal of the International Society of Sports Nutrition found that adding 0.05ml to a bottle of water for 10 days improved power and time to exhaustion.
Drink: A few drops in your water bottle.
Caffeine is the key ingredient here and there’s heaps of evidence that supports its use as a natural performance booster.
Drink: One or two cups of coffee (delivering 3-9mg of caffeine) around 45 minutes before your run.
4/ Beet kvass
A traditional Ukrainian tonic, this fermented drink contains health-boosting bacteria, vitamins and electrolytes.
Buy: From the Cultured Cellar (£5.99 for 500ml)
5/ Himalayan pink salt
It contains 84 minerals, including sodium, iron, magnesium, phosphorus and calcium.
Eat: Use as seasoning and add to water/coconut water for extra on-the-run electrolytes.
6/ Coconut water
A natural sports drink that works well as a fuel/electrolyte source on short, light runs. It’s a good source of potassium, but heavier sweaters may need a little more sodium than it provides.
Drink: On shorter runs.
High in nitrates, which become nitric oxide in the body, widening blood vessels and making more oxygen available to your muscles. An Exeter University study found beetroot could help you exercise for up to 16 per cent longer.
Drink A glass of beetroot juice (around 280ml) a day in the week before a race.
The stem of this vegetable contains potassium to help control heart rate and blood pressure, phosphorus to help buffer lactic acid and copper to aid absorption of its iron content.
Eat: Grate into a smoothie with ginger and apple juice.
9/ Cayenne pepper/chilli
Full of capsaicin, which enhances endorphin production and blood flow. Some research suggests it also has painkilling effects.
Eat: Add two teaspoons of cayenne pepper to yoghurt or milk smoothies, or try it in your race drink.
They add sugars, electrolytes and flavour to water, and they contain vitamin C, a powerful antioxidant.
Drink: Add to water for your runs.
11/ Dark chocolate
Small amounts could boost endurance. When scientists at the University of California gave mice a purified form of cacao’s primary ingredient, epicatechin, twice daily for 15 days, the rodents were able to cover 50 per cent more distance on a treadmill than a control group.
Eat: Half a square (5g) of dark chocolate daily is enough to gain the benefits.
Photos from Getty Images