Running has become a highly popular activity to keep and stay fit. Whether you’re training for a charity run, or just joined the local Park Run, it’s likely you’ll want to improve your performance. Here we look at the best foods tested in clinical trials that may give you a boost.
Athletes commonly use safe supplements to enhance their performance both in training and on the track, and now recreational athletes (people that run, cycle or swim for a hobby) are also turning to natural supplements to help them get the best out of their performance.
Beetroot juice has attracted some attention recently due to its ability to raise nitric oxide in the blood,which increases blood flow, oxygen uptake in the lungs and enhance the ability of muscles to work better (1).
However, many supplements appear to only work in recreational sports, and not sports at elite level, where muscle has significantly adapted to high levels of exercise (4).
A recent systematic review (a study that collects the results of studies) found that beetroot may actually help us run for longer, but when taken regularly, it could also help improve overall fitness too (2).
So beetroot may be good for long distance running as it delays the onset of fatigue; but not all studies agree, and there are likely to be individual variations according to how fit we are already, our age and how well we respond to different foods.
Tart cherry juice
Tart cherry, otherwise known as Montmorency cherry, is available as a cherry concentrate such as CherryActive, and is gaining a lot of interest due to its anti-inflammatory and anti-oxidant properties (5).
This is particularly important during the training phase, because you will want to recover quickly before the next session.
It is even possible that taking this supplement just once could help improve a personal best, because it may offset some of the damage caused by muscle injury (10), and thus reduce post exercise pain too (11).
Unfortunately, there are not many studies conducted on cherry juice and exercise performance, and at the time of writing, I could not find a systematic review. However, the science to date is promising and more studies are definitely welcome in this area.
Overall, I would suggest that giving it a go for your own curiosity is worth exploring, and let the rest of us know whether you find any difference.
Green tea is gaining popularity in Europe, although it’s a beverage that’s much more associated with Asian culture, particularly China and Japan.
It’s known for its antioxidant properties, and has been widely studied for its effects on cancer!
But it has also been studied in sports medicine too, because it is believed to have an effect on performance.
Unfortunately, the consistency of the studies is lacking and so the results are somewhat mixed, but there is some evidence that taking green tea extract (as a supplement) may help you burn more fat during exercise (12, 13).
This could allow you to run a little further as you won’t be completely reliant on stored glucose from your muscles to get you to the finish line.
But the effect is more pronounced in people who haven’t exercised at a high level for very long (14), and so may benefit those doing their first charity run rather than seasoned marathon-runners.
Blueberries are another great source of antioxidants, and have long been hailed as a “superfood” by the food industry.
When we think of antioxidants, most of us probably think of vitamin C, but blueberries are a rich source of plant compounds known as anthocyanins.
When we do strenuous exercise, we create inflammation within the body, because we’re essentially damaging tissue as as work our muscles.
Anything we can do to reduce the inflammation makes training much easier, and one study found that taking 250g of blueberries daily did just that (15).
Anthocyanins may also have an effect on lactate production too.
A study looking at another source of this compound in blackcurrants found that 6g blackcurrant powder per day reduced the amount of lactate in the blood (16), suggesting that it is being cleared from the blood as quickly as it’s being produced.
As we gain fitness and adapt to exercise, our ability to clear lactate improves, which is one of the reasons we are able to perform better when we train at higher intensity.
However, research into blueberry or blackcurrant anthocyanins is very limited, with only a few studies published to date.
So no firm conclusions could be drawn from this, but again – adding a handful of either into a smoothie or scattered over your breakfast can’t hurt can it?
Naturally I saved the best until last! Cocoa, the primary ingredient in good quality dark chocolate, has also been studied in connection to exercise performance.
Like green tea, cocoa is rich in a plant compound called catechins.
These compounds have been extensively studied on all variety of health-related topics from cancer to weight-loss.
However, studying cocoa and exercise is very much in its infancy. One of the first studies to actually observe an effect chocolate has on VO2max (measure of oxygen intake and how quickly it is used, which improves as you get fitter!) was as late as 2015.
In this study, 40g of dark chocolate daily showed improvements in distance covered and VO2max compared to a control group (17).
However, this was in cycling so it is unknown whether this would have the same effect on running.
Moreover, they used a commercial chocolate bar, Dove Dark Chocolate, that doesn’t state the percentage level of cocoa solids, so it’s difficult to really conclude whether it was the cocoa that had this affect or something else in the bar.
Sadly, a slightly earlier study found no effect of chocolate on cycling performance (18), but studies that combine chocolate with other food groups found that it might have a synergistic effect.
If you want to take a little chocolate with you to give you an extra boost on a long run, I think a few squares of good quality, high cocoa (70% or higher), will give you both the glucose you need to get you to the end as well as any potential impact from cocoa compounds.
However, I do need to temper this with a little warning: most chocolate you find in high street shops have had their active compounds stripped in a process called dutching.
There’s always a sting in the tail!
Seb is a writer and blogger of food and nutrition. He holds a bachelors and a masters degree in nutrition science, and has studied sports and exercise nutrition at postgraduate level. He specialises in plant-based nutrition and believes passionately that we can all live with a little less meat.