Two young women running ina green park. Both dark skinned and dark brown hair

Training and nutrition underpin athletic performance, however, dietary supplements may play a smaller, but important role. Our Sports and Spinal Dietitian team has taken us on a deep dive into dietary supplements. They have explained how they can both positively and negatively impact an athlete’s performance.

The Supplement Situation

Supplements are very popular in the sporting world; from sports foods that provide additional macronutrients, to powders that may improve alertness. There are so many supplements available on the market at the moment. It can be difficult to know which ones may be beneficial or harmful to an athlete’s health and performance.

A new study from the International Journal of Sports Nutrition and Exercise Metabolism summarized the evidence surrounding popular sports supplements. The study provides guidance for professionals and athletes regarding efficacy, dosage, and side effects.

Micronutrients That Often Require Supplementation

In athletes, common vitamins and minerals play a crucial role in factors that contribute to sports performance. For example, regulating energy production and creating new cells and proteins. An athlete who is deficient in fundamental nutrients may be more prone to illness and injury or unable to train as effectively. Calcium, Vitamin D, and iron are three nutrients often lacking in the general population and athlete’s diets.

Calcium & Vitamin D

Calcium and Vitamin D are essential for bone health and important in maintaining immunity and muscle strength. Dairy products are the best source of calcium. While Vitamin D is synthesized in the skin from direct contact with sunlight but it can also be obtained from some foods.

Athletes may be at risk of insufficient Vitamin D during colder seasons where there is less exposure to the sun. Whereas, athletes who avoid dairy products are at higher risk of insufficient Calcium intake. It makes sense for athletes to prioritize Calcium and Vitamin D given the absolute necessity for muscular and bone health in competitive sports.

Iron Suboptimal

Iron levels in an athlete are equally as important as Calcium and Vitamin D. Iron levels can vary depending on the athlete’s iron intake, whether it be choosing foods low in bioavailable iron, or increased iron.

Iron is necessary to enable athletes to undertake high-altitude training, as well as enable rapid growth. Iron levels can also lessen as a result of lose through excess sweat, urine, or faeces.

Female athletes are also more prone to having a low iron status compared to males due to blood loss during menstruation. An athlete who does not obtain adequate iron may notice fatigue, shortness of breath, and changes in overall strength, which are essential components for optimal performance.

‘Calcium, vitamin D and iron are three nutrients often lacking in the general population and athlete’s diets.’

Sports Foods and Functional Foods

Athletes often have higher macronutrient and electrolyte requirements than the average person. It can be more challenging to meet an athlete’s needs in certain situations such as during an event or between races. Sports foods can be a convenient source of nutrients like carbohydrates, protein, fat or electrolytes. Such foods help athletes to sustain or recover from physical activity by replenishing stores before, during or after an event.

Foods proved to improve athletic performance when used correctly include;

  • Sports and energy drinks
  • Sports gels and sports confectionary
  • Electrolyte replacement supplements
  • Protein supplements
  • Liquid meal supplements
  • Sports bars and protein-enhanced foods

Keep in mind these supplements are often expensive, and everyday foods may be an appropriate option depending on your activity and overall goal. See the images below for more nutrients and vitamins that are commonly found in an athlete’s diet 👇

Supplements That Directly Improve Sports Performance

When someone says ‘sports supplements’, caffeine or creatine are probably the first that come to mind, and for good reasons too. Nitrate, beta-alanine, and sodium bicarbonate may also improve performance to some degree depending on the dosage and situation.

Supplements That Indirectly Improve Performance

There are also supplements that can indirectly affect sports performance by influencing factors that contribute to this such as enhancing immunity, assisting with training capacity, and contributing to beneficial physique changes like an increase in muscle mass.

Summing Up Supplements

There is a lot to consider when adding a sports supplement into an athlete’s routine. It is important to ensure athletes follow a balanced meal plan tailored to their needs prior to supplementation. This is so they can maintain good health through high-impact sports and intense training programs.

Supplements should also be trialed well before the event day to ensure dosage aligns with expected results, and side effects can be controlled. It is also crucial to perform a risk analysis weighing the benefits of the supplement with the risk of potential doping due to contamination.


Written By Our Sports & Spinal Dietitian Team

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