Sports nutrition: the complete guide

Sports nutrition isn't just for professional athletes. Whether you do 3 strength training sessions a week or are preparing for a triathlon, adapting your diet to your training improves your performance, recovery, and body composition. This guide provides the scientific principles and practical applications.

Steps

1

Calculate your training TDEE

Regular athletes have significantly higher caloric needs than sedentary individuals: 2,800 to 4,500 kcal/day depending on the sport, intensity, and frequency. Underestimating your needs is the most common mistake and leads to RED-S (Relative Energy Deficiency in Sport), a syndrome that impairs performance and health.

2

Periodize your nutrition

Your macronutrient needs vary depending on your training phase. During high-volume periods: more carbs and calories. During tapering: a slight caloric reduction while maintaining carbs. During competition phase: carb loading. During the off-season: maintenance eating.

3

Time your nutrition around workouts

The pre-workout meal (2-3h before) provides energy. Intra-workout nutrition (for sessions over 90 min) maintains performance. The post-workout meal (within 2h) kicks off recovery. This timing isn't magic, but it optimizes long-term results.

4

Hydrate strategically

Start every session well-hydrated (clear urine). During effort, drink 150 to 250 mL every 15 to 20 minutes. For efforts lasting more than 60 minutes, add electrolytes (sodium: 300-700 mg/L). After exercise, drink 1.5 L for every kg lost during the session.

5

Supplement smartly

Only a few supplements have solid evidence: creatine monohydrate (3-5 g/day), caffeine (3-6 mg/kg before effort), beta-alanine (3-6 g/day for efforts lasting 1 to 10 minutes), and beetroot juice (nitrates for endurance). The rest is mostly marketing.

6

Monitor your performance markers

Signs of inadequate nutrition: strength plateaus, chronic fatigue, frequent infections, recurring injuries, sleep disturbances, and loss of motivation. Keep a food and training journal to correlate your diet with your performance.

Nutritional Periodization

Nutritional periodization adapts your diet to your training cycle, just as the training itself is periodized. In the general preparation phase (high volume), carbohydrate needs are at their peak (5 to 8 g/kg) to fuel long sessions and recovery.

In the specific preparation phase (high intensity), protein is kept high (1.6-2.2 g/kg) to support muscle adaptations, and carbs are adjusted based on session intensity. On rest days, carbs can be reduced in favor of quality fats.

During tapering and competition, the goal is to maximize glycogen stores while maintaining weight. Carb loading (3 days of high carbs at 8-10 g/kg) is relevant for events over 90 minutes. This periodized approach is used by Olympic and professional teams.

Pre, Intra, and Post-Workout Nutrition

The ideal pre-workout meal combines complex carbs and protein, with low fat and fiber for fast digestion. Examples: white rice with chicken, oatmeal with protein powder, or toast with scrambled eggs. Consume it 2 to 3 hours before your session.

During effort (intra-workout), nutrition is only necessary for intense sessions lasting more than 60 to 90 minutes. In this case: 30 to 60 g of fast-acting carbs per hour (carb drink, gel, banana) and water with electrolytes. For strength training under 90 minutes, water alone is usually enough.

Post-workout, aim for 20 to 40 g of protein and 0.8 to 1.2 g/kg of carbs within 2 hours. A whey shaker with a banana is classic, but a real meal is just as effective. The anabolic window is wider than supplement marketing wants you to believe.

Guide to Sports Supplements

Creatine monohydrate is the most studied and effective supplement: it increases strength and power performance by 5 to 10%, promotes hypertrophy, and improves recovery. 3 to 5 g per day, with no loading phase required, is safe for the kidneys in healthy individuals.

Caffeine (3 to 6 mg/kg, 30 to 60 minutes before exercise) improves endurance, reduces perceived exertion, and increases power. Beetroot juice (500 mL or 6-8 mmol of nitrates, 2 to 3 hours before) improves endurance by 1 to 3% through nitric oxide production.

BCAAs, glutamine, pre-workout boosters, and "gainers" lack solid evidence of benefits beyond what a proper diet provides. Invest in real food rather than expensive supplements with marginal effects.

FoodCraft Tip

Athlete TDEE with the FoodCraft Calculator

The FoodCraft TDEE calculator offers activity levels tailored for regular and intense athletes. Select your training frequency and type to get an accurate estimate of your caloric needs, which are much higher than recommendations for sedentary people.

Meal Plans for Athletes

The FoodCraft meal planning AI creates menus tailored for athletes: high caloric density, sufficient protein, carbs adjusted to training volume, and optimized timing around sessions. Ideal for no longer having to overthink every meal.

Frequently Asked Questions

Should I eat differently on rest days?
Yes, moderately. On rest days, slightly reduce carbohydrates (as there's no exercise expenditure) but keep protein high for recovery. Total calories can be reduced by 200 to 400 kcal compared to training days. This calorie cycling approach optimizes body composition.
What is RED-S?
RED-S (Relative Energy Deficiency in Sport) is a syndrome caused by a chronic energy deficit relative to training demands. It affects hormones, bones, immunity, mental health, and performance. It affects both men and women, not just weight-category sports. A warning sign: loss of periods in female athletes.
Is protein powder essential for an athlete?
No, it's a convenient supplement. If your whole food diet covers your protein needs (1.6-2.2 g/kg for strength training, 1.2-1.6 g/kg for endurance), powders offer no additional advantage. They are useful when time or appetite is lacking, or just after training for convenience.
Can you perform well on a vegan diet?
Yes, provided you plan carefully. Many high-level athletes are vegan. Key focus areas are protein (quantity and variety of sources), B12 (mandatory supplementation), iron, zinc, creatine (not present in plants), and DHA. Guidance from a sports nutritionist is recommended.
How long before exercise should I eat?
A full meal 2 to 3 hours before, a light snack 30 to 60 minutes before. The larger and higher in fat/fiber the meal, the more time it needs to digest. A banana or a cereal bar 30 minutes before is well tolerated by most people. Find your own tolerance by experimenting during training.

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