What sports supplements can improve endurance?

Evidence-Based Sports Supplements for Improving Endurance

Caffeine, creatine, beta-alanine, and nitrates are the most effective supplements for improving endurance performance, with caffeine showing the strongest immediate effects and creatine providing the most comprehensive benefits for both training capacity and performance.

Caffeine: First-Line for Immediate Endurance Enhancement

• Mechanism: Acts as a central nervous system stimulant and adenosine receptor antagonist 1
• Benefits: Reduces perception of fatigue, enhances endurance, improves repeated sprint performance, skill execution, and cognitive function 1
• Dosage Protocol:
  • 3-6 mg/kg body mass in anhydrous form (pill/powder) consumed ~60 minutes before exercise
  • Alternative: Lower doses (<3 mg/kg, ~200 mg) provided both before and at half-time with a carbohydrate source
  • Can be delivered through sports foods or coffee 1
• Caution: Individual response varies significantly; start with lower doses to assess response. Side effects at higher doses include anxiety, nausea, insomnia, tremors, and reduced sleep quality. More serious side effects include tachycardia and arrhythmias 1, 2

Creatine: Best for Long-Term Endurance Development

• Mechanism: Increases muscle creatine stores, enhancing phosphocreatine resynthesis 1
• Benefits:
  • Improves high-intensity repeated sprint performance
  • Enhances training capacity and chronic adaptations (muscle strength, power, lean body mass)
  • May support brain function 1, 2
  • Particularly beneficial for endurance sports requiring multiple intensity surges or end spurts 3
• Dosage Protocol:
  • Loading phase: ~20 g/day divided into four equal doses (5g four times daily) for 5-7 days
  • Maintenance phase: 3-5 g/day as a single dose 1, 2
  • Tip: Concurrent consumption with protein/carbohydrate (~50g each) enhances muscle creatine uptake 1
• Caution: May cause 1-2 kg body mass increase after loading phase; lower dose approaches (2-5 g/day for 28 days) may avoid this 1

Beta-Alanine: For High-Intensity Endurance Components

• Mechanism: Increases muscle carnosine, an important intracellular buffer 1
• Benefits: May improve high-intensity exercise, repeated sprint performance, and enhance training capacity 1, 4
• Dosage Protocol: Daily consumption of ~65 mg/kg body mass via split-dose regimen (0.8-1.6g every 3-4 hours) up to 6.4 g/day over 4-12 weeks 1
• Caution: Possible skin rashes and/or transient paraesthesia (skin tingling) 1

Nitrates: For Aerobic Efficiency

• Mechanism: Increases tissue nitrite and nitric oxide, reducing oxygen cost of exercise via enhanced function of type II muscle fibers and reduced ATP cost of force production 1
• Benefits: Improves economy and endurance exercise performance; some evidence for football-specific intermittent exercise performance 1
• Dosage Protocol: Acute benefits seen within 2-3 hours following a nitrate bolus of 5-9 mmol (310-560 mg); prolonged intake (>3 days) may also benefit performance 1
• Food Sources: High nitrate-containing foods include leafy green and root vegetables (spinach, rocket salad, celery, beetroot) 1
• Caution: Individual response to supplementation varies; possibility of minor gastrointestinal upset; beetroot juice may discolor urine 1

Safety and Quality Considerations

• Choose supplements tested by reputable third-party testing programs (e.g., 'Informed Sport', 'HASTA') to reduce risk of contamination 1
• Be aware that 15-25% of nutritional supplements contain substances not declared on the label 2
• The principle of strict liability means ignorance of prohibited substances in a product is not an acceptable excuse for athletes subject to drug testing 1

Sports Drinks: Limited Evidence

• Designed to replace water, electrolytes, and energy before/after exercise
• Scientific evidence supporting improved water absorption and endurance maintenance has limitations
• Most studies have methodological issues (lack of blinding) and focus on young male endurance athletes, limiting translation to other populations 1

Remember that while these supplements can enhance performance, they should complement rather than replace proper training methods, adequate nutrition, and appropriate recovery strategies.