What helps muscle and exercise performance?

This page is educational. It cannot provide a personal training, nutrition or anti-doping plan.

You might be interested in strength, power, endurance, recovery, muscle size or everyday function. These are different outcomes. Protein and creatine have different evidence; training and adequate food also matter. A change in lean mass does not automatically mean better strength or function.12

On this page
  1. Define performance
  2. Food and training are part of the comparison
  3. Health and sport rules differ
  4. Compare protein products
  5. Creatine
  6. BCAAs
  7. Peptides and sport
  8. Weight loss and lean mass
  9. Growth-hormone peptides
  10. Sources
Follow this question
Muscle & exercise Choose a step to explore this subject in more detail.
  1. 1Define performance
  2. 2Food and training are part of the comparison
  3. 3Health and sport rules differ
  4. 4Compare protein products

Define performance

Strength, repeated intense efforts, endurance, recovery and body composition are different things to measure. Check which one a study looked at and what it compared.12

Food and training are part of the comparison

A powder or bar is one way to consume food, not a guarantee of better results. Compare it with ordinary food, the training programme and what participants in a study actually ate.12

Health and sport rules differ

A product can be legal to sell but restricted in sport. Its contents or purity may also be uncertain. Check current anti-doping rules separately from health evidence.56

Compare protein products

Serving size, ingredients, allergens and storage all matter. Read how to compare protein products.

Creatine

Creatine is well studied for some exercise outcomes, with separate safety questions. Read the creatine profile.

BCAAs

Compare claims about branched-chain amino acids with adequate dietary protein and what studies actually measured. Read the BCAA guide.

Peptides and sport

Sport rules and health evidence are separate questions. Peptides and sport. MOTS-c is sometimes described as an exercise peptide: see what the human and mouse studies measured. Research on SS-31 asks another muscle question: compare walking, fatigue and strength outcomes.

Weight loss and lean mass

Body scans can estimate lean mass, but they do not directly measure strength. Read what the tirzepatide scan study found.3

Growth-hormone peptides

A change in a hormone measurement is not a direct measure of muscle or strength. Read the guide to growth-hormone peptide claims.4

Sources, kept close.

Selected supporting sources; this is not a complete literature review.

  1. Health Benefits of Physical Activity for AdultsCenters for Disease Control and Prevention · public-health guidanceAccess checked 2026-11-05 · Source date: 2026-03-10 · General population guidance; it does not establish the effect of a particular supplement or provide individual medical advice.
  2. Healthy dietWorld Health Organization · public-health guidanceAccess checked 2026-11-05 · Source date: 2026-01-26 · Population guidance; it does not test individual supplements or establish a personal diet.
  3. Body composition changes during weight reduction with tirzepatide in the SURMOUNT-1 studyDiabetes, Obesity and Metabolism / PubMed · Randomised trial DXA substudy; manufacturer-supportedAccessed 2026-11-05 · Source date: 2025
  4. Prolonged stimulation of growth hormone and insulin-like growth factor I secretion by CJC-1295 in healthy adultsJournal of Clinical Endocrinology & Metabolism / PubMed · Two randomised double-blind placebo-controlled human hormone studies; 2006Accessed 2026-11-04
  5. 2026 Prohibited ListWorld Anti-Doping Agency · International sport rule list, effective 2026Accessed 2026-11-04
  6. Reducing Supplement RiskU.S. Anti-Doping Agency · US anti-doping supplement guidanceAccessed 2026-11-04

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