Table 1.

List of potential dietary supplements to augment acute and chronic high-intensity interval training.

Dietary Supplement/Strategy	Possible Mechanism(s) of Action	Potential Acute Benefits	Potential Chronic benefits	Recommended Dosing Protocol
Creatine	↑ PCr; ↑ Glycogen; ↑ buffering capacity; ↑ calcium handling; Anti-oxidant (?); ↓muscle protein breakdown; ↓ inflammation	↑ high-intensity capacity; ↑ recovery between bouts	↑ training volume (?); ↑ VT and critical power males. VO2max and time trial performance active females	Loading phase: 20 g/day; Maintenance phase: 5 g/day; relative dose: 0.1 g/kg/day
Caffeine	Adenosine receptor antagonist; ↓ perception of pain and exertion; ↑ calcium handling and muscle relaxation; ↓ muscle damage and inflammation (?); ↑ glycogen re-synthesis	↑ total work; ↑ peak power and force production; ↑ muscular endurance; trained > untrained	performance, ↓ muscle damage	3–6 mg/kg 45–60 min before exercise.
Sodium Bicarbonate	↓ metabolic acidosis	↑repeated sprints; ↑ high-intensity exercise	↑ lactate threshold; ↑ time to exhaustion; ↑ peak power	Acute loading: 0.2–0.3 g/kg 1–3 h before exercise (>5 mmol/L increase in circulating bicarbonate) Serial loading: 0.4–0.5 g/kg/day divided into three–four servings throughout the day
Beta-Alanine	↑ intramuscular carnosine and buffering capacity; ↓ glycogen utilization; ↓ oxidative stress; ↑ threshold for neuromuscular fatigue; ↓ feelings of fatigue	↑ high-intensity exercise (2–4 min in duration)	↑performance (?); on VT or critical power	3.2 to 6.4 g/day for 2–6 weeks
Nitrate	↑ nitric oxide; ↑ blood flow; ↑ muscular contractility; ↓ O2 cost during exercise; muscle fiber type remodeling	↑ high-intensity exercise; ↑ mitochondrial biogenesis	↑ performance (?); ↑ VO2max	8–13 mmol of nitrate/day 2–2.5 h before exercise
Protein and amino acids	↑ recovery; ↑ muscle protein kinetics; supports ↑ mitochondrial biogenesis	high-intensity exercise; ↑ mitochondrial biogenesis (?)	performance or VO2max, may benefit the immune system	1.2–2.2 g/kg/day

Abbreviations: ↑ increase; ↓ decrease; ↔ no effect; VT = ventilatory threshold, PCr = Phosphocreatine, VO₂max maximal oxygen consumption.