4.3 Discuss the use of supplements, micronutrients, protein, caffeine and creatine products for improved performance

1. Supplements, micronutrients, protein, caffeine and creatine for improved performance

In sport, supplements are products used to add to the diet, not replace it. They may provide nutrients, energy, fluid, or compounds that aim to support health, recovery, or performance. They are available as powders, tablets, capsules, drinks, gels and bars.

A key point is that a supplement is not automatically useful just because it is legal, popular, or heavily marketed. Some supplements are evidence-based and may improve performance in the right context. Others are mainly convenient. Some offer little benefit and may create unnecessary cost, side effects, or risk.

1.1 When supplements may improve performance

Supplements are most likely to improve performance when they are used for a clear reason. This usually occurs when they:

• correct a deficiency that is limiting performance
• help an athlete meet nutrition needs when food is difficult to manage
• allow more accurate dose and timing
• target a specific performance mechanism, such as reducing fatigue or improving rapid ATP resynthesis

Supplements are much less likely to help when an athlete already meets their needs through food, when the product does not match the sport, or when side effects outweigh the benefit.

A strong discussion of supplements should show both sides. Supplements can be useful, but they should be judged according to:

1.2 Safety and anti-doping considerations

Even when a supplement is legal, that does not guarantee effectiveness, quality, or safety. Dose, timing, and product quality all matter. A supplement can reduce performance if it causes gastrointestinal upset, sleep disruption, unwanted mass gain, or poor recovery.

In drug-tested sport, contamination is also a serious issue. Some products may contain undeclared ingredients, so unnecessary supplement use should be avoided. This means the safest approach is usually food first, with supplements used only when there is a clear need, an evidence-based purpose, and appropriate guidance.

2. Micronutrients for improved performance

Micronutrients are vitamins and minerals needed in small amounts, but they are essential for processes that support performance. These include energy metabolism, red blood cell production, oxygen transport, bone health, immune function, muscle contraction, and tissue repair.

The most important idea is this: micronutrients do not directly boost performance unless they correct a deficiency. If an athlete already has adequate stores, taking extra usually does not produce better performance and may cause problems.

2.1 Micronutrients most linked to performance

For most athletes, the first response to a low micronutrient intake should be to improve the diet, not immediately add a supplement. Supplementation is most appropriate when:

• a deficiency has been diagnosed
• dietary intake is consistently too low
• the athlete has higher-than-normal losses or requirements
• food alone is unlikely to restore status effectively in the short term

This means micronutrient supplements are mainly used to remove a limiting factor, not to create a performance advantage beyond normal healthy function.

Example: Emily is a 17-year-old middle-distance runner who begins to feel unusually fatigued in training. Sessions that were previously manageable become difficult, and Emily becomes short of breath more easily. A blood test shows iron deficiency anaemia. With medical guidance, Emily begins iron supplementation and improves dietary iron intake. Over time, energy levels improve, training quality rises, and performance returns. This shows that micronutrient supplementation can improve performance when it corrects a real physiological limitation.

3. Protein products for improved performance

Protein is important for muscle repair, adaptation, and recovery from training. It supplies amino acids that help repair muscle tissue and support longer-term changes such as increased strength and muscle hypertrophy.

Protein does not mainly improve performance by providing immediate fuel during exercise. Its main performance value is that it supports recovery and helps athletes adapt to training over time.

3.1 When protein products may be useful

Most athletes can meet protein needs through food, including lean meat, fish, eggs, dairy, legumes, tofu, nuts and seeds. However, protein products such as shakes, powders and bars may still be useful because they are convenient and consistent.

They are especially helpful when:

• an athlete struggles to meet total daily protein needs through food alone
• appetite is low after training
• meals are delayed because of school, work, travel, or competition
• a quick recovery option is needed after exercise

A practical strategy is to spread protein intake across the day and include around 20 to 30 g of high-quality protein after training when recovery is important.

3.2 Protein products are not superior

A key understanding is that protein supplements are not superior to food. Their main value is convenience. Whole foods also provide other important nutrients, such as iron, zinc, and calcium, which many protein powders do not provide in the same way.

Athletes generally need more protein than sedentary adults, often around 1.2 to 2.0 g/kg/day depending on the type of training and the goal. However, extra protein beyond what the athlete needs does not continue to improve performance.

Protein products may become unhelpful when they:

• replace balanced meals too often
• reduce carbohydrate intake needed for training and competition
• contribute to unwanted energy intake and body mass gain
• cause digestive discomfort
• create unnecessary cost

This means protein products can support performance, but only when they help an athlete meet needs more effectively than food alone in a specific situation.

Example: Liam is an 18-year-old rugby player who aims to support recovery and strength gains. Most of his protein comes from meals, but after gym sessions he adds one shake to help him reach his daily target. This works well because the shake complements his meals rather than replacing them. A teammate uses multiple shakes each day on top of meals, eats less carbohydrate, and gains unwanted body fat. This shows that protein products can help when they fill a gap, but excess use is not automatically beneficial.

4. Caffeine products for improved performance

Caffeine is a stimulant found in coffee, tea, chocolate, cola, energy drinks, tablets, gels and chewing gum. It may improve performance by reducing perceived fatigue and increasing alertness, concentration, and reaction speed.

This can be useful in:

• endurance events, where fatigue tolerance matters
• intermittent team sports, where repeated efforts and decision-making are important
• sports requiring focus, concentration, and quick responses

4.1 When caffeine is most useful

Caffeine tends to be most effective when dose and timing are carefully controlled. In many cases, relatively low-to-moderate doses of around 1 to 3 mg/kg can help performance. It is commonly taken around 30 to 60 minutes before exercise, although products such as gum may act more quickly.

Coffee can be used, but tablets, gels, and gum often allow more precise dosing. This matters because the same substance that helps one athlete may reduce performance in another if the dose is too high.

4.2 Limits and cautions

Caffeine is one of the best-known performance supplements, but it is not universally helpful. Side effects may include:

• jitters or tremor
• anxiety or over-arousal
• higher heart rate
• gastrointestinal upset
• poorer fine motor control
• sleep disruption

This last point is very important. A caffeine strategy that slightly improves one session or event may still be a poor choice if it disrupts sleep and reduces recovery later.

It is important to note that more caffeine is not always better. Caffeine may improve performance when dose, timing, and individual tolerance are well matched. It may harm performance when the athlete becomes too anxious, shaky, or unable to sleep.

Example: Sarah is a 17-year-old netball player playing several games in one day. In training, she tries a large energy drink before a practice match and feels jittery and anxious. Her shooting becomes less controlled and she struggles to sleep that night. She later trials a smaller dose and finds it improves alertness without the same side effects. A teammate finds caffeine increases anxiety even at low doses and decides not to use it. This shows that caffeine can help, but only when it suits the individual athlete.

5. Creatine products for improved performance

Creatine is stored mainly in muscle as phosphocreatine (PCr). During short, explosive efforts, phosphocreatine helps rapidly resynthesise ATP, which is the immediate energy source for muscular contraction.

Because of this, creatine is most useful in activities that rely on short bursts of maximal or near-maximal effort.

5.1 When creatine may improve performance

Creatine monohydrate is the most researched form and is strongly supported for improving performance in:

• strength and power sports
• repeated sprint efforts
• explosive movements such as jumping, lifting and throwing
• training situations where slightly higher quality or volume improves long-term adaptation

Creatine may also support gains in fat-free mass when combined with resistance training, because athletes can often maintain better training quality over time.

5.2 Practical use

Creatine is not an acute supplement like caffeine. Caffeine can have a short-term effect soon after use, but creatine works differently. It gradually increases the amount of stored creatine in the muscles. This may help the body resupply energy during short, high-intensity efforts such as sprinting, jumping, tackling or repeated powerful movements.

5.3 Limits and cautions

Creatine is not equally useful for every athlete. It is usually less helpful for pure endurance events, and the increase in body mass from greater water storage in muscle may be a disadvantage in sports where power-to-weight ratio is very important.

Possible issues include:

• short-term mass gain
• bloating or gastrointestinal discomfort
• little benefit if the sport does not rely on repeated high-intensity efforts

This means creatine can improve performance, but its value depends heavily on the demands of the sport.

Example: Matt is a sprinter who begins creatine supplementation and notices improved performance in repeated sprint sessions and resistance training. He can maintain quality for longer and complete slightly more work in explosive lifts. Marcus, a middle-distance runner, gains body mass and notices little benefit during longer runs. This shows that creatine is much better suited to anaerobic, high-intensity performance than to predominantly aerobic events.