With conflicting research and such a vast array of products available, nutritional supplements are without a doubt a minefield. From creatine to glucosamine, how can you be sure that what you are taking is both safe and effective and that you are not essentially pouring your money down the drain?

Here are the nutritional supplements that sports scientists have found to show strong evidence of a performance effect and will actually give you bang for your buck:

1. Caffeine

Good news for all you coffee lovers; it has been well documented that caffeine ingestion prior to exercise can improve endurance performance. It is thought that caffeine has a positive effect on your perception of effort and can help you to feel more alert, focused and energised.

Caffeine ingestion prior to exercise can improve endurance performance.

You should aim to consume 3-5mg of caffeine per kilogram of bodyweight. 45-60 minutes before a race or a hard and/or long training session. To give you an idea of how much that is, a single espresso contains 75mg, a can of Red Bull 80mg and one Pro Plus tablet, 50mg.

However, it’s worth considering that not everybody responds to caffeine in the same way. The bad news is that if you habitually consume a lot of caffeine then it’s likely you will have become desensitised to its ergogenic effect and may not feel the benefits. If you can bear it then eliminating caffeine from your diet in the 2 weeks leading up to a big event before re-introducing it on race day, should be enough to elicit a performance enhancing benefit.

2. Beetroot juice

In recent years there has been a lot of research on the use of nitrates, such as those found in beetroot juice , as a sports supplement. Nitrate ingestion prior to exercise has been found to reduce the oxygen cost of submaximal exercise, making it an ideal supplement for endurance events.

The research suggests that you should use beetroot juice in the 2-6 days leading up to a race and then 2.5 hours from the start. One of the most popular nitrate supplements on the market currently are ‘Beet It’ shots. These contain a concentrated form of beetroot juice, saving you from having to gulp down gallons of the red stuff!

3. Beta-alanine

Research has shown that beta-alanine has a positive effect on lactate threshold, which is a crucial component of endurance performance. Ingesting beta-alanine for 4-8 weeks has been shown to elevate muscle carnosine levels. Increasing the amount of carnosine in the muscles means that the body is capable of buffering more hydrogen ions and therefore lactic acid, which ultimately improves lactate threshold.

4. Probiotics

Probiotics have long been used to help settle gastrointestinal issues, such as bloating and stomach upsets, however there is growing evidence to suggest that they offer wider health benefits such as improved immunity and heart health. Probiotics contain ‘friendly’ bacteria that help to maintain a healthy balance of bacteria in your gut. Maintaining a healthy gut is crucial as it functions as a barrier to potentially harmful bacteria and helps with greater nutrient absorption.

Probiotics can help you to limit the number of days of missed training through illness by improving immune function.

It is also thought that probiotics can help you to limit the number of days of missed training through illness by improving immune function. There’s good evidence to support that these friendly bacteria reduce the duration of upper respiratory tract infections. In one study published in the British Journal of Sports Medicine , 20 elite distance runners who used probiotics during four months of winter training experienced milder symptoms and shorter bouts of respiratory illness.

Preliminary research has also indicated that probiotics can improve heart health and reduce the risk of coronary heart disease by creating acids that counter cholesterol production.

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