Supplementation can be a beneficial way to help meet nutritional needs or to help maximize performance.
The exact dosing of creatine is still unknown, however, a high-dose, short-term protocol of around 20 g/day for 5 days or a low-dose, long-term protocol of around 3-5 g/d for around 30 days are what are currently recommended by the literature8.
The greatest amount of research and safety data has been produced for creatine monohydrate, and there appears to be no rationale for recommending any other form besides for the monohydrate form8.
It has been established that moderate to high caffeine doses, of 5-9 mg/kg body mass, ingested before and during exercise can increase endurance performance in laboratory and field settings9. However, doses this high can lead to some side effects such as gastrointestinal upset, nervousness, mental confusion, inability to focus, and disturbed sleep. Lower doses of no more than 3 mg/kg body mass can also increase performance without the side effects that come from the higher doses9.
Caffeine can be used as an ergogenic aid in both endurance and short-term high-intensity sports. The effects of caffeine are best maintained when administered in alternate forms other than capsules/tablets and coffee. Some alternate forms include sports/energy drinks, gels, gum, bars, and dissolvable mouth strips9.
Vitamin D plays a big role in maintaining the health and performance of an athlete. Vitamin D deficiencies are linked to an increased risk of acute illness, inflammatory injury, stress fractures, muscle pain/weakness, and reduced muscle performance10.
The human requirement for vitamin D can be met solely from skin exposure to the sun and it can be found in limited dietary sources10. It can be found in foods such as10:
- fatty fish (salmon, mackerel, sardines, and tuna)
- fortified milk
- soy milk
- fruit juice
- egg yolks
Signs and symptoms of a deficiency include elevated parathyroid concentration, weak bones, bone pain, decreased bone density, increased bone fracture risk, muscle weakness and discomfort, atrophy of type II fibers, high frequency of infectious illness10.
Vitamin D recommendations may be met by 5 (for fair-skinned individuals) to 30 (for darker-skinned individuals) minutes of sun exposure without sunscreen to the arms, legs, and back at close to solar noon several times a week. You can also take a supplement of up to 2,000 IU/day10.
No Vitamin D supplementation should begin without the direction of a doctor because of the risk of toxicity10.
Antioxidants (vitamins C and E)
These are found to help minimize free-radical damage to skeletal muscle which in turn reduces muscle fatigue, inflammation, and soreness11. You should not take more than 2,000 mg/day of vitman C or more than 1,500 IU/day of vitamin E11. Any supplementation should be discussed with your primary care doctor before you begin taking them.
Iron helps to increase the oxygen uptake in the body, reduce heart rate, and decrease lactate concentrations during exercise. Men and postmenopausal women should take 8 mg/day while premenopausal women should take 18 mg/day11.
Any dietary deficiency should be addressed with a physician before trying to correct it with a dietary supplement. Any dietary supplement taken should be taken as instructed by the manufacturer or your physician.