Sports Nutrition Basics Buying Guide
Sports nutrition has been complicated by supplement marketing to the point where many athletes overthink timing windows while getting the basics wrong. The research hierarchy is clear: total daily calories and protein intake drive 80% of performance and body composition outcomes. Nutrient timing (pre/post workout meals) accounts for maybe 10%. Supplements — even the good ones — account for 5–10% on top of solid fundamentals.
How We Compiled This Guide
We reviewed systematic reviews and position papers from the International Society of Sports Nutrition (ISSN), American College of Sports Medicine (ACSM), and Journal of the International Society of Sports Nutrition. Cross-referenced with evidence-based nutrition guidance from sports dietitians. Supplement recommendations reflect only interventions with multiple replicated randomized controlled trials — not single studies or industry-funded research.
The Foundation: Daily Protein and Calorie Targets
Nothing in sports nutrition matters if daily totals aren't right. Evidence-based targets:
Protein: 1.6–2.2g per kg bodyweight per day for active individuals. For a 170 lb (77 kg) person: 123–170g protein daily. This is the most important nutrition number for muscle building and maintenance. Spread across 4–5 meals (30–40g per meal) for optimal muscle protein synthesis. Sources: chicken breast (31g/4oz), Greek yogurt (17g/6oz), eggs (6g/egg), salmon (34g/4oz), whole milk (8g/8oz).
Carbohydrates: 3–7g per kg bodyweight depending on training volume. Endurance athletes need the high end; strength athletes doing 4 sessions/week need 4–5g/kg. Carbs are the primary fuel for moderate-to-high intensity training — cutting carbs below 3g/kg impairs training performance measurably.
Fat: 20–35% of total calories. Fat is essential for hormone production (including testosterone). Don't go below 20% — low-fat diets reduce testosterone by 10–15% in active men (JAMA study, 1996, replicated multiple times).
Total calories: Body composition changes require calorie surplus (muscle gain) or deficit (fat loss). No supplement or timing protocol overrides caloric balance — this is physics, not nutrition science debate.
Pre-Workout Nutrition: What to Eat and When
2–3 hours before training: Full mixed meal: 60–80g carbohydrates + 30–40g protein + moderate fat. Example: chicken breast + rice + vegetables. This is the optimal timing for digestion — the meal is processed, nutrients are available, and the stomach is settled.
30–60 minutes before training: Small, easily digested carb + protein snack: banana (27g carbs) + protein shake or Greek yogurt. Avoid high-fat, high-fiber foods this close to training — they slow gastric emptying and cause GI discomfort during exercise.
Fasted training (early morning): If training within 30 minutes of waking: 20–30g fast-digesting carbs (sports drink, banana, white bread) + 10–20g protein is sufficient. Performance won't be maximized but is adequate for most non-competitive training. For serious performance: a full pre-workout meal is worth waking up 2 hours earlier to eat.
Post-Workout Nutrition: The Anabolic Window (Wider Than You Think)
The "30-minute anabolic window" is real but overstated. Current research shows muscle protein synthesis is elevated for 3–5 hours post-training, and the window is most relevant when you haven't eaten for 3+ hours before training. Practical protocol:
Within 2 hours post-training: 25–40g protein + 40–80g carbohydrates. Whey protein is digested fastest (peak MPS at 60 minutes) — relevant for athletes who train multiple sessions per day. Casein protein (slower digesting) is better for before bed. For most athletes training once daily: protein source matters less than hitting total daily protein target.
Carbohydrates post-workout: necessary for glycogen replenishment, especially critical for endurance athletes and those training 5+ days per week. Strength athletes with more than 24 hours before next session: carb timing matters less.
Supplements: What the Evidence Actually Supports
Creatine monohydrate (Tier 1 evidence, 1,000+ studies): 3–5g daily (no loading phase needed). Increases phosphocreatine stores for short-burst, high-intensity efforts (lifting, sprinting). Improves strength gains by 5–10% in resistance training and reduces recovery time. CreaPure brand ($25–$35/500g) is the quality benchmark — many generic brands use lower-purity creatine.
Caffeine (Tier 1 evidence): 3–6mg/kg bodyweight, 30–60 minutes before training. 200–400mg for most adults. Improves endurance performance by 3–5%, reduces RPE (perceived exertion), and sharpens focus. Coffee works equally well as supplement caffeine ($0.50/cup vs. $1–$2/serving for pre-workout formulas). Tolerance builds with daily use — cycling off 1–2 weeks per month maintains effectiveness.
Protein powder (practical tool, not essential supplement): Whey protein is the most convenient way to hit protein targets when whole food isn't accessible. Optimum Nutrition Gold Standard Whey ($55/5 lbs, 24g protein/serving) is the benchmark. Plant-based: Momentous Essential Pea Protein ($50/lb) or Orgain Organic Protein ($30/2 lbs). Not magic — equivalent to food protein at the same gram quantity.
Beta-alanine (Tier 2 evidence): 3.2–6.4g/day. Buffers lactic acid, improving endurance at 1–4 minute intensities (400m runners, cyclists, MMA athletes). Causes harmless skin tingling (paresthesia). Less relevant for strength training or long-endurance work.
Supplements without meaningful evidence: BCAAs (redundant if protein intake is adequate), glutamine (absorbed from gut before reaching muscle), testosterone boosters (virtually none work in healthy adults), most "proprietary blends" in pre-workout products.
Common Mistakes to Avoid
Mistake 1: Optimizing timing while ignoring total intake. Pre-workout meal timing is irrelevant if you're 50g protein below your daily target. Fix daily totals first, then optimize timing.
Mistake 2: Expensive supplement stacks before basics are covered. A $3/serving pre-workout stack providing 5% performance improvement is worse value than the same money spent on whole food protein providing 25g protein per serving.
Mistake 3: Cutting carbs for an endurance goal. Low-carb training impairs performance at intensities above 70% VO2 max — i.e., any training that's actually challenging. Some fat adaptation strategies exist for ultra-endurance events; they're inappropriate for general fitness training.
Mistake 4: Ignoring hydration. A 2% drop in body weight from sweat reduces aerobic performance by 10–20% (well-replicated finding). Drink 400–600ml 2 hours before training; replace sweat losses during training at ~200–300ml every 15 minutes of intense exercise.
What We Recommend
Supplement stack with evidence: Creatine monohydrate 5g/day (CreaPure brand, $25–$35), whey protein if needed for protein targets (Optimum Nutrition, $55), caffeine via coffee. Everything else is optional at best. For nutrition tracking: MyFitnessPal (free tier) or Cronometer (free) to verify you're hitting protein and calorie targets. See our strength training equipment guide, post-workout recovery guide, and best fitness trackers for complete training support.