{"compared":[{"id":"creatine","name":"Creatine","category":"amino_acid","evidence_quality":"strong","dosing":"The standard protocol involves a loading phase of 20g/day (divided into 4x5g doses) for 5-7 days to rapidly saturate muscle stores, followed by a maintenance dose of 3-5g/day (or 0.1g/kg of body mass). Alternatively, a consistent dose of 3-5g/day without loading will achieve full saturation within 28 days. For older adults or those with higher muscle mass, the upper end of maintenance (5-10g/day) may be more effective. Creatine monohydrate remains the gold standard form due to superior bioavailability and cost-effectiveness.","key_findings":[{"finding":"Creatine increases lean mass by approximately 0.36% per week and strength by 1.09% per week when combined with resistance training.","direction":"positive","study_type":"meta-analysis","pmid":"12433852"},{"finding":"Upper-body exercise shows a significantly larger effect size (ES 0.42) compared to lower-body exercise (ES 0.21) for performance gains.","direction":"positive","study_type":"meta-analysis","pmid":"12945830"},{"finding":"In older adults (65+), creatine significantly increases fat-free mass and improves functional performance in tasks like the chair stand test.","direction":"positive","study_type":"meta-analysis","pmid":"24576864"}],"safety_summary":"Creatine is remarkably safe for long-term use in healthy individuals. The most common side effect is initial weight gain (1-2kg) due to water retention. High doses (150mg/kg) are contraindicated in McArdle disease as they increase myalgia. There is no evidence of kidney damage in individuals with h…","study_count":555},{"id":"beta-alanine","name":"Beta-alanine","category":"amino_acid","evidence_quality":"strong","dosing":"The standard protocol involves a loading phase of 4.8 to 6.4 g/day for 4 to 10 weeks to maximize muscle carnosine stores. This is typically divided into doses of 0.8 to 1.6 g every 3-4 hours to minimize paraesthesia. Following the loading phase, a maintenance dose of 1.2 g/day is recommended to keep carnosine levels elevated. Studies frequently utilize powder or sustained-release tablet forms.","key_findings":[{"finding":"Median 2.85% improvement in exercise measures, specifically in efforts lasting 60-240 seconds.","direction":"positive","study_type":"meta-analysis","pmid":"22270875"},{"finding":"Significant overall effect size of 0.18 for exercise capacity, with greater efficacy (ES = 0.49) for bouts of 0.5-10 minutes.","direction":"positive","study_type":"meta-analysis","pmid":"27797728"},{"finding":"Co-supplementation with sodium bicarbonate yields the largest performance effect (ES = 0.43).","direction":"positive","study_type":"meta-analysis","pmid":"27797728"}],"safety_summary":"The primary side effect is paraesthesia (tingling/itching sensation), which is harmless but can be uncomfortable; it is dose-dependent and typically subsides within 60-90 minutes. No significant adverse effects on blood chemistry, liver enzymes, or kidney function have been reported at standard dos…","study_count":337}]}