Overview
The transcript explains four legal sports supplementsâcreatine, caffeine, bicarbonate, and nitratesâtheir mechanisms, performance benefits, and side effects for A-level nutrition.
Supplements Summary
| Supplement | What It Is | Primary Mechanism | Performance Benefits | Key Side Effects | Best Suited For |
|---|
| Creatine (creatine monohydrate) | Powder/tablet increasing phosphocreatine (PC) stores | Increases muscle PC; extends ATP-PC energy availability | Slightly longer maximal efforts (~+2 s); more reps; increased strength and power | Water retention and weight gain; muscle cramps; long-term effects unknown, possible liver/kidney stress | Maximal, short-duration efforts (sprints, heavy lifts) |
| Caffeine | Common stimulant in coffee/energy drinks | Heightens CNS activity; increases fat metabolism (glycogen sparing) | Faster reactions; better focus; reduced fatigue; improved endurance via glycogen sparing | Diuretic dehydration; insomnia; withdrawal (headaches, shakes); possible palpitations | Endurance performers; sports needing alertness |
| Sodium Bicarbonate (bicarbonate) | Alkali (baking soda) consumed in solution | Raises blood pH; buffers lactic acid accumulation | Work harder/longer with less burn; improved high-intensity duration | Gastrointestinal distress: bloating, nausea, vomiting; unpleasant taste | Events with high lactate (e.g., 400 m, repeated high-intensity) |
| Nitrates (e.g., from beetroot) | Dietary nitrates converted to nitric oxide | Vasodilation increases blood flow and oxygen delivery | More O2 to muscles; higher energy production; quicker recovery; delayed fatigue | Dizziness/light-headedness; long-term unclear; possible carcinogenic risk noted | Endurance and mixed-intensity sports seeking oxygen delivery gains |
Creatine
- Increases intramuscular phosphocreatine stores; supports ATP-PC system.
- Extends maximal, anaerobic work from ~10 s to ~12 s in bouts.
- Cumulative training effect yields more reps and total load over months.
- Leads to gains in maximal strength, power, and explosiveness.
- Side effects: rapid water-weight gain; cramps; unknown long-term, probable liver/kidney strain.
Caffeine
- Central nervous system stimulant; commonly consumed in drinks.
- Improves reaction time, focus, and reduces perceived fatigue.
- Increases fat breakdown; shifts substrate use toward fats.
- Glycogen sparing preserves carbohydrate stores for later exercise phases.
- Enhances endurance performance by delaying carbohydrate depletion.
- Side effects: diuretic-induced dehydration; insomnia; withdrawal symptoms; possible palpitations.
Sodium Bicarbonate (Bicarbonate)
- Alkali ingestion slightly raises blood pH above neutral (~7).
- Buffers/neutralizes lactic acid produced during hard efforts.
- Allows higher intensity and longer duration before severe muscle burn.
- Practical benefits in events with pronounced lactic accumulation.
- Side effects: gastrointestinal upset (bloating, nausea, vomiting); poor palatability.
Nitrates
- Found in root vegetables (notably beetroot); stored as nitric oxide.
- Nitric oxide causes vasodilation, increasing muscle blood flow and oxygen.
- Benefits include higher energy production, faster recovery, delayed fatigue.
- Side effects: dizziness/light-headedness in some; long-term effects unclear.
- Possible carcinogenic risk mentioned in syllabus; caution on excessive intake.
Key Terms & Definitions
- ATP-PC system: Immediate energy system using ATP and phosphocreatine for up to ~10 s.
- Phosphocreatine (PC): High-energy compound in muscle; rapidly regenerates ATP.
- Central nervous system (CNS) stimulation: Increased neural activity improving alertness and reaction.
- Glycogen sparing: Greater fat use early in exercise preserves glycogen for later stages.
- Lactic acid buffering: Neutralizing acidity to reduce muscular burn and fatigue.
- Vasodilation: Widening of blood vessels, increasing blood flow and oxygen delivery.
Action Items / Next Steps
- Match supplement choice to event demands: ATP-PC efforts, endurance, or high-lactate events.
- Weigh benefits versus side effects (hydration, sleep, GI tolerance, weight).
- If trialing, test timing/doses in training, not competition.
- Monitor hydration with caffeine; plan bathroom access with bicarbonate.
- Consider dietary sources (e.g., beetroot) if avoiding commercial nitrate products.