The health and exercise performance effects from blackcurrant, is this the beginning of the purple reign?
A diet high in fruits and vegetables is known to positively influence our health and this is partly attributable to the array of polyphenols they contain. These are the molecules that give them their array of bright colours, but also give them a natural protection against ultraviolet radiation (i.e. sunlight).
There are several thousand polyphenols naturally occurring, with one category called anthocyanins. If you picture strawberries, blackberries, cherries, raspberries or blackcurrants, they are all brightly coloured which comes from their high anthocyanin content. Research has shown anthocyanins to have anti-inflammatory and antioxidant effects, which naturally has led to some of these being called ‘super-foods’. Some of the research done by Dr Matthew Cook has examined how the blackcurrant can affect our health, but also our exercise performance.
When the margins of success within elite level support are so narrow, elite athletes regularly look for ways to support their training and improve their performance. Sports nutrition and supplements are regularly used to this effect; however, the sports nutrition market is filled with products which deliver claims, but often do not have evidence to support their use. Therefore, research is essential to identify if supplements are effective.
In one of the initial studies conducted by Dr Cook for his PhD at the University of Chichester, trained cyclists were given blackcurrant capsules or a placebo for a week of and their exercise performance in a 16.1 km (10 miles) cycling time-trial was then examined. The study was designed so that it was double-blind and cross over, which meant that the cyclists completed the time-trial twice, once with the blackcurrant and once with the placebo. The double-blind meant that the researchers and the participants did not know whether they were taking the blackcurrant or the placebo in order to prevent bias within the study. The results demonstrated that participants on average completed the time-trial 2.4% quicker following the blackcurrant in comparison to the placebo. The results of study were published within the European Journal of Applied Physiology and were the first in a series of studies examining how effective blackcurrant supplementation was for exercise performance.
Follow up studies have examined the effect of blackcurrant on the energy source being used during exercise. The studies again used a one-week intake of blackcurrant capsules and examined the contribution of fat and carbohydrate to the energy being used during the cycling exercise. Interestingly, the study found that blackcurrant could increase the amount of fat being used during 120-minutes of moderate intensity cycling by over 20%. These findings could be important to ultra-endurance athletes where they compete for prolonged time periods, or those who want to lose weight. As a result, follow up research being conducted at the University of Worcester is examining further if blackcurrant can alter fat burning over different exercise intensities.
Other studies being conducted by Dr Cook and colleagues from the School of Sport and Exercise Science at the University of Worcester are examining if the benefits of blackcurrant on exercise performance can be seen in older adults and if there are also effects on cognitive function. In aging there is a decline in the ability to perform exercise as a result of muscle loss and a reduced capacity of the cardiovascular system. As a result, these changes and limitations to exercise capacity can also influence our ability to do functional tasks such as intense walking. There are also changes in cognitive function, such as reaction time and our ability to process information and make decisions quickly (consider the cognitive skills required when we are driving a car). Effects on these would indicate if blackcurrant is something older adults should consider consuming more of to help with these tasks.
If you would like more information on the research on the current studies being conducted at the University, please feel free to get in contact with Dr Mathew Cook.
Dr Matthew Cook is a Lecturer on the Sport and Exercise Science BSc in the School of Sport and Exercise Science