Does L-arginine increase endurance?

Discover the power packed into this amino acid when it comes to long-lasting muscle performance What do fans of endurance sports like long-distance running, cycling, hiking or swimming have in common? At some point, we’ve all wondered whether anything can give our muscles a helping hand. Step forward L-arginine. Handpicked content: 11 ways to fit exercise into your daily routine

What is L-arginine?

It’s an amino acid, an important building block of protein, used for muscle growth and tissue repair.¹ It’s also needed by the body to help heal wounds and remove waste products from muscles, such as urea, in our urine.² But L-arginine has another crucial job within the body; it is converted into nitric oxide, a neurotransmitter that helps blood vessels relax and widen.³

How can L-arginine help with muscle endurance?

Doctors think that nitric oxide’s effect on blood vessels means your muscles will receive more blood – and so more nutrients and oxygen – boosting your workout and recovery, and relieving muscle fatigue.⁴ It’s also thought that L-arginine benefits include its ability to reduce the amount of lactate – a type of lactic acid – that accumulates in the muscles during high intensity exercise. Because lactate triggers muscle fatigue, reducing levels can in turn increase stamina.⁵ In a 2010 study by the University of Exeter, researchers gave nine healthy men aged between 19 and 38 years a supplement of L-arginine before high intensity cycling challenges. Results showed that the L-arginine significantly increased their stamina, allowing the men to exercise for up to 20% longer than those who took a placebo.⁶ In a different study, published in Biology of Sport in 2014, nine professional wrestlers took an L-arginine supplement before exercise. The scientists found that the amino acid boosted the time it took the wrestlers to reach exhaustion by nearly 6%, compared to a placebo. However, the team also said that more research is needed to understand exactly what causes this effect.⁷ Handpicked content: How good is cycling for you?

The best food sources of L-arginine

Our bodies make some L-arginine naturally, but it’s also found in foods that are high in protein, including:⁸

• lentils
• chickpeas
• soybeans
• wheatgerm
• wholegrains
• nuts
• seeds
• eggs
• dairy foods

Most people get enough L-arginine from their diet so a deficiency is quite rare.⁹ If you’re thinking about taking a supplement, talk to your doctor first because it can interact with some medications. It may also have an effect on your breathing if you have asthma.^10,11 Handpicked content: The hidden health benefits of L-arginine

Advice is for information only and should not replace medical care. Please check with your GP before trying any remedies.

Shop our Vitamins and Supplements range Sources 1. Medical News Today. L-arginine. Potential benefits, side effects, and risks. Available from: https://www.medicalnewstoday.com/articles/318174.php 2. University of Michigan. How much do you NO? Available from: http://umich.edu/~medfit/supplementation/NO.html 3. Habib S and Asif A. Biochemistry of Nitric Oxide. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3068772/ 4. As Source 2 5. Schaefer A, et al. L-arginine reduces exercise-induced increase in plasma lactate and ammonia. Available from: https://www.ncbi.nlm.nih.gov/pubmed/12215958 6. Bailey SJ, et al. Acute L-arginine supplementation reduces the O2 cost of moderate-intensity exercise and enhances high-intensity exercise tolerance. Available from: https://www.ncbi.nlm.nih.gov/pubmed/20724562 7. Yavuz HU, Turnagol H and Demirel AH. Pre-exercise arginine supplementation increases time to exhaustion in elite male wrestlers. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4135062/#CIT0002 8. As Source 1 9. ND Healthfacts. Arginine. Available from: http://www.ndhealthfacts.org/wiki/Arginine 10. Mayo Clinic. L-arginine. Available from: https://www.mayoclinic.org/drugs-supplements-l-arginine/art-20364681 11. As Source 1