Which evidence‑based dietary supplements are recommended for a healthy adult preparing for a bodybuilding competition?

Evidence-Based Supplements for Bodybuilding Competition Preparation

For a healthy adult preparing for a bodybuilding competition, prioritize creatine monohydrate (3-5 g/day), caffeine (3-6 mg/kg body weight), and beta-alanine (2-6 g/day in divided doses), as these are the only supplements with robust evidence for enhancing performance outcomes relevant to contest preparation. 1, 2

Primary Recommended Supplements

Creatine Monohydrate

• Take 3-5 g daily throughout all training phases, including contest preparation 2
• Increases phosphocreatine stores in skeletal muscle, improving ATP production during high-intensity resistance training 2
• Enhances skeletal muscle mass, strength/power, and muscular endurance with strong safety profile for long-term use 2
• Commonly used by bodybuilding coaches during bulking phases, though evidence supports year-round use 3

Caffeine

• Consume 3-6 mg/kg body weight approximately 1 hour before training 2
• Reduces perceived pain while enhancing focus and alertness during training sessions 2
• Widely used by competitive bodybuilders with documented ergogenic benefits 1, 3

Beta-Alanine

• Take 2-6 g daily in divided doses to minimize paresthesia (tingling sensation) 2
• Elevates intramuscular carnosine, which buffers hydrogen ions and delays fatigue during high-intensity exercise 2
• Most effective for activities lasting 1-4 minutes, relevant to typical bodybuilding training sets 2

Protein Supplementation Strategy

Protein Intake Targets

• Consume 2.3-3.1 g/kg of lean body mass per day during contest preparation 1
• This translates to approximately 3 g/kg total body weight during the cutting phase based on competitive bodybuilder practices 3
• Distribute protein across 3-6 meals daily, with 0.4-0.5 g/kg body weight consumed before and after resistance training 1

Protein Quality Considerations

• Prioritize whole-protein foods over isolated amino acid supplements because mixed-macronutrient meals suppress protein breakdown through insulin secretion while supporting protein synthesis 4
• Whey protein supplements are acceptable and commonly used, but should be consumed with carbohydrates and fats to maximize anabolic response 4
• Isolated essential amino acids lack co-nutrients needed to stimulate insulin and suppress protein breakdown, making them inferior to whole-protein sources 4

Leucine Enhancement

• Consider adding 2.5 g crystalline leucine to meals containing ~20 g protein to further enhance muscle protein synthesis 5, 4
• However, leucine alone does not replicate the insulin-mediated benefits of whole-protein foods 4

Supplements Lacking Strong Evidence

Not Recommended as Primary Ergogenic Aids

• Branched-chain amino acids (BCAAs) in isolation are inferior to whole proteins 4
• Chromium picolinate, glutamine, and omega-3 fatty acids lack robust evidence for contest preparation benefits 1, 3
• Poly-vitamins may lead to excessive micronutrient intake (>1000% RDA) above tolerable upper limits when combined with fortified foods 6

Macronutrient Distribution Framework

During Contest Preparation (Cutting Phase)

• Set caloric intake to achieve 0.5-1% body weight loss per week to maximize muscle retention 1
• Protein: 2.3-3.1 g/kg lean body mass (highest priority) 1
• Fat: 15-30% of total calories 1
• Carbohydrate: remainder of calories after protein and fat targets are met 1

Meal Frequency and Timing

• Consume 3-6 meals per day with protein distributed evenly 1, 7
• Nutrient timing and frequency have minimal effect on fat loss or lean mass retention beyond total daily intake 1
• Fasted cardiovascular exercise is commonly practiced but lacks strong evidence for superiority 7

Critical Pitfalls to Avoid

Dangerous Practices

• Never engage in severe dehydration or electrolyte manipulation in the final days before competition—this is dangerous and may not improve appearance 1
• Avoid combining multiple stimulants, as this increases cardiovascular risk 3
• Do not rely on isolated amino acid supplements as primary protein sources 4

Carbohydrate Loading

• Increasing carbohydrate intake at the end of preparation has theoretical rationale but is understudied 1
• If pursued, practice carbohydrate loading before competition and assess individual response 1

Mental Health Considerations

• Be aware of increased risk for eating and body image disorders in aesthetic sports 1
• Access to mental health professionals is important for competitors 1

Evidence Quality Note

The bodybuilding supplement literature is generally dated (most from 1980-1990s) and of poor methodological quality 6. The recommendations above prioritize the most recent systematic reviews 1 and evidence-based supplement analyses 2 over older observational studies of bodybuilder practices. The three supplements with the strongest evidence—creatine, caffeine, and beta-alanine—should form the foundation of any supplementation strategy, with protein optimization achieved primarily through whole foods rather than isolated supplements. 4, 1, 2