The foundations of sport performance are training and nutrition, with nutrition providing a supportive role in enhancing training adaptation. Nutrition is the sum of food and nutrients consumed by a person. The food you eat is broken down and digested by the body into its substrates; protein, fats, and carbohydrates which are stored in your muscles, fat, and liver. These are also referred to as macronutrients. These micronutrients are either stored, utilized or excreted in a certain period of time. When you are active and training, it is these substrates that are called up by mitochondria to create energy and fuel your workout (Stellingwerff et al, 2019).

Tip: You are not what you eat - - - you are what you absorb.

Micronutrients are the vitamins and minerals needed by the body in very small amounts. Vitamins and minerals work by combining with enzymes in our bodies, acting as ‘biochemical sparkplugs’ - helping many thousands of life-sustaining cellular chemical reactions to occur that would otherwise not occur or occur too slowly to sustain life. Their impact on your body’s health is critical.

During exercise, your body works hard to keep up with the demands called for. It needs to draw on energy from the macronutrients and requires micronutrients to use those macronutrients to power you through your activity and post-recovery.

Vitamins and minerals play a fundamental role in a plethora of human processes that are of significance to athlete health and performance. Movement-dependent functions, such as energy metabolism, oxygen transport, red blood cell production, immune function, muscle growth/repair, and the prevention of oxidative damage and bone health, are all dependent on vitamins and minerals in some way.

Because we cannot manufacture them, vitamins and minerals MUST be present in sufficient quantities and in the right ratios in the foods we eat if we are to thrive and be healthy. (Close, et al, 2022). Research shows that many athletes are deficient in key vitamins, for a variety of reasons (Harju et al, 2022).

Western Diet
The Western diet which is high in processed foods, seed oils, and sugar, does not provide the range of nutrients needed. The growing amount of intensively reared and processed/refined foods on our supermarket shelves can often mean lower nutrient contents, and evidence is growing that even a carefully-balanced diet may not be sufficiently rich in some key nutrients for some individuals for optimum health, particularly for certain nutrients such as vitamin D3 (Hall et al, 2019).

Modern Agriculture Practices
Commercial agriculture is heavily dependent on pesticides. As an example, modern agricultural methods that favor NPK (nitrogen, phosphorus, and potassium) fertilizers create a relative magnesium deficiency in the soil. These fertilizers bind the magnesium, making it unavailable to the crop, and absent from the food produced in the crop (Chaudhry et al, 2021).

Quality of the Food
In the today’s world of intensive agriculture, where crops may be force grown in soils depleted of trace minerals, fruits and vegetables are routinely picked unripe and then artificially stored and ripened, and where nutrient depleting food processing and refining practices becomes ever more commonplace, it becomes very difficult for even the most health conscious athlete to be certain about the nutritional content of the food on their plates.

Many modern food processing methods result in a significant loss of nutrients. Research shows that many fruits and vegetables grown today have fewer nutrients available than years ago (Davis et al, 2004).

Marketing
Popular sponsors of many athletic events are sugary drinks and carbohydrate sports drinks products (which don’t contain the nutrients present in natural carbohydrates), and highly processed ‘energy’ and ‘protein’ bars which contain a lot of sugar. A regular intake of these products can lead to poor nutrient composition and poor quality within the diet, even if energy intake is appropriate (Peeling et al, 2023). These are not part of a healthy diet and can even impair performance.

The average person consumes about 50 grams (12 teaspoons) of sugar a day, which is almost double the recommended daily maximum. Energy drinks, gels, and bars are crammed with sugar. A single energy bar can contain more than half of the recommended daily limit (Committee on Nutrition and the Council on Sports Medicine and Fitness, 2011). Sugar slows food’s travel through the gastrointestinal tract. A recent study found that the consumption of sugar-sweetened beverages for 15 days in active, healthy young males lead to impaired physical performance and a lower VO2 Max score (Baleeiro et al, 2021).

Risk of Deficiency
Athletes will have different nutritional needs compared with the public, resulting from the demands of training on the body. There are a multitude of interacting factors that can contribute to sub-optimal nutrient status in athletes; these factors include processes such as increased excretion in sweat, urine and feces, increased turnover, decreased absorption in the gastrointestinal tract, and biochemical adaptation to training (van der Beek et al, 1991).

Female athletes have distinct biological attributes which make their nutrient needs unique, and which often lead to micronutrient deficiencies (Rushton et al, 2010; Muscogiuri et al, 2019). Menstrual blood losses and hormonal fluctuations result in a greater iron requirement compared with males. Indeed, this is reflected in the RDI guidelines for the general population, where iron consumption recommendations in females are more than double that of males (18 versus 8 mg/day) (Health & Council, 2006). To compound this issue, female athletes commonly follow diets that are restrictive, including vegetarian or vegan diets low in quality iron sources (Sim et al, 2019), or those limiting either carbohydrate or energy intake (McKay et al, 2022), which have been shown to contain lower amounts of dietary iron. Accordingly, inadequate energy intake, and therefore lower dietary iron intake, contributes to the higher incidence of iron deficiency seen in female athletic populations (Coates et al, 2017).

Clear associations between menstrual function, bone health and energy availability have previously been described via the Female Athlete Triad (Nattiv et al, 2007) and more recently as part of the Relative Energy Deficiency in Sport (REDs) model (Mountjoy et al, 2018). Female athletes with amenorrhoea (lack of a period) often present with poor bone mineral density, bone microarchitecture and/or bone turnover markers, placing them at an increased risk of stress fractures (Ackerman & Misra, 2011). Considering that peak bone mass is often attained by 30 years of age, and that 95% of a young woman’s peak bone mass is present by age 20 this would substantially increase the risk of developing early onset osteoporosis, which will present as a major complication in late-life (Bernstein et al, 2003).

Help with Recovery
A compromised or restricted nutrient intake not only impacts an athlete’s energy status, but also their opportunity to replace any vitamins and minerals utilized or excreted during exercise (i.e. B vitamins in energy production or electrolytes and iron in sweat) or those used in the recovery from/adaptation to the training stimulus (i.e. in red blood cell production) (Peeling et al 2009; Thomas et al, 2016). For example, it is not uncommon for energy availability to be compromised in endurance athletes with heavy daily training schedules, where repeated bouts of exercise throughout the day can negatively impact the opportunity to adequately replenish energy requirements between sessions. (Beck et al, 2015).

Tip: Its all about recovery

During physical activity, your body consumes more oxygen and this leads to oxidative stress, which produces reactive oxygen and nitrogen species (aka free radicals) and oxidized molecules in muscle and other bodily tissues. This process can lead to inflammation during the recovery process, which may impact the ability of an athlete to absorb various nutrients at the level of the gut (McLung et al, 2014), which over time can also contribute to a greater exposure to risk of nutrient deficiency.

Supplements
A recent meta-analysis found greater gains in fat-free mass and strength in healthy adults who consume multi-ingredient supplements, that influence multiple physiological endpoints. Included in that diet were vitamins, minerals, fatty acids, amino acids, macronutrients such as carbs, fat and proteins, along with bioactive compounds like quercetin (O’Brien et al, 2021).

So, it may be important for some athletes to consider a vitamin or mineral supplement to meet their daily needs.

Types of vitamins
Vitamins are generally classified as water soluble or fat soluble. Water-soluble vitamins are not stored in our bodies and generally require daily food intake. These are the B vitamins (B1, B2, B3, B5, B6, B8, B9, B12) and vitamin C (Chawla & Kvarnberg, 2014), differentially distributed in vegetable and animal foods, milk, and its derivatives.

Fat-soluble vitamins are absorbed along with fats in the diet and are stored in the body’s fatty tissue and in the liver. They are often remembered with the acronym DAKE, which stands for vitamin D, A, E and K. Vitamin K is poorly stored in the tissues and therefore requires a continuous dietary supply (Stevens, 2021). Fat-soluble vitamins are found mainly in fruit and vegetables, except for vitamin D, which is synthesized by the human body. Importantly, vitamins play a fundamental role in the regulation of many chemical reactions essential for life (Brancaccio et al, 2022).

Testing
This is not to make any supplement claim, but to explain the biochemistry of supplements that are important to athletic performance, and the research behind them.

Testing your nutritional status is always recommended so you at least have a baseline. If any element tests as low, that can be specifically addressed through diet or specific oral supplements or both.

To the right of this page are a list of key nutrients that help active people maintain their training. Each vitamin or mineral is explained for the role it can play in health and fitness. Our goal is to help you understand the importance of nutrients and how to ensure that your diet includes what you need (Larson-Meyer et al, 2018).

The basic tests are (think of it as putting air in the tires):

• Vitamin D
• Vitamin E
• Red Blood Cell Magnesium
• Serum Calcium
• Serum Iodine
• Red Blood Cell Zinc
• Red Blood Cell Copper
• Red Blood Cell Selenium
• PIVKA II (a rough measure of K)
• K-1 if not taking a K supplement
• CoQ10
• Vitamin A
• Beta Carotene
• Iron

References

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