Swimming Pre-Race Nutrition: Carbohydrate Loading Strategy for the Three Days Before Competition

Introduction

Three days before a race, many swimmers significantly reduce their training volume (the tapering period), but their diet often does not adjust accordingly. In fact, the tapering period is the golden window for carbohydrate loading: with reduced training volume and lower muscle glycogen depletion, increasing carbohydrate intake simultaneously can bring muscle glycogen stores up to 1.5–2 times the normal level. This extra stored glycogen can provide a sustained and steady energy supply during the race, with particularly notable benefits for middle- and long-distance events of 200 m and above.

The Science Behind Carbohydrate Loading

Muscle glycogen is the primary fuel for aerobic swimming. Under a normal diet, muscle glycogen stores are approximately 300–400 mmol/kg. Through pre-race carbohydrate loading, stores can be elevated to 500–600 mmol/kg or even higher.

The effects of loading are most pronounced under the following conditions:

• Race duration exceeds 60–90 minutes (e.g., 1,500 m freestyle, marathon swimming)
• The athlete has completed adequate taper training before the race
• Carbohydrate loading is paired with sufficient fluid intake (glycogen storage requires water—approximately 3 g of water per 1 g of glycogen)

Three-Day Pre-Race Meal Plan

Three Days Before (D-3): Transition Period

Two Days Before (D-2): High-Carbohydrate Period

• Consume 8–10 g of carbohydrates per kilogram of body weight
• For a 65 kg athlete, the target is 520–650 g of carbohydrates
• Maintain normal protein intake (1.5–1.7 g/kg)
• Reduce fat to “make room” for carbohydrates
• Choose low-fiber carbohydrates: white rice, white noodles, white toast, sweet potato, banana, honey (to avoid digestive issues)

One Day Before (D-1): Conservative Maintenance

• Maintain carbohydrate intake at D-2 levels or slightly reduce
• Avoid trying any new foods
• Drink plenty of water and pay attention to electrolyte replenishment
• Avoid high-fat, high-fiber, and spicy foods
• Eat dinner early (18:00–20:00 the night before the race) to allow ample time for digestion

Race-Day Nutrition

2–3 Hours Before the Race:

• Light breakfast: 2–3 slices of white toast + jam + low-fat milk
• Carbohydrate target: 50–70 g
• Protein: 10–15 g
• Avoid high-fat and high-fiber foods

30–60 Minutes Before the Race (if needed):

• Half a banana or 1 packet of sports gel
• Hydrate with 200–300 ml of water

Between Multiple Events (1–3 hours between races):

• Quick carbohydrates: banana, congee, energy bar
• Small amount of protein
• Avoid large amounts of solid food

Common Myths About Carbohydrate Loading

• Myth 1: Loading will cause weight gain that affects performance
  Muscles will indeed gain slight weight from stored glycogen and water (500 g–1 kg), but this represents ample energy, not a burden. For swimming, the extra water may actually help with heat dissipation.

• Myth 2: Short-distance events don’t need loading
  Ultra-short distances like 50 m and 100 m rely primarily on phosphocreatine for energy, so the benefits of carbohydrate loading are more limited. However, for athletes competing in multiple events (several races in one day), glycogen stores still matter.

Practical Recommendations

• Before non-major races, practice carbohydrate loading during a taper week following regular training to learn how your body responds
• Stick to familiar foods during the loading period; don’t try new foods or new restaurants
• Athletes with sensitive stomachs can take a more conservative approach to carbohydrate loading (7–8 g/kg)—peace of mind comes first
• When competing away from home (e.g., national or international competitions), plan carbohydrate sources from local foods in advance
• Proper mental relaxation is also part of race preparation—avoid adding anxiety by over-focusing on diet

Conclusion

Pre-race carbohydrate loading is a well-supported scientific strategy, but the execution needs to be individualized. Starting from D-3, progressively increase carbohydrate intake, choose low-fiber foods, pair with adequate hydration, and maintain blood sugar stability on race day with light meals. Ample glycogen reserves are your energy guarantee for maintaining speed to the finish line.

Related Reading

• Carbohydrate Stacking Before a Swim Race: A Three-Day Pre-Race Meal Plan
• Carb-Loading Three Days Before a Race: Complete Plan and Practical Template
• Carbohydrate Loading in the Swim Taper Week: Energy Storage Strategies for Distance Athletes
• The Science of Glycogen Supercompensation: How to Properly Carbohydrate Load Before a Race