Increase muscle mass

What this outcome means

Muscle mass is how much skeletal muscle your body carries — the tissue that powers movement, lifts loads, and shapes your strength and metabolism. On DoseRank it maps to a defined health outcome built from human studies on lean body mass, muscle cross-sectional area, and grip and strength measures – data sourced from open sources and specialized resources. DoseRank is not medical advice.

Who it's for

Building strengthLifters and athletes working to add lean size and power.

Age-related declineOlder adults losing muscle as the years add up.

Rebuilding after layoffComing back from injury, illness, or long time off training.

Stack buildersAlready taking supplements such as L-Leucine and want the dose right.

Evidence level

92Strong

L-Leucine – has strong public evidence. DoseRank looks at both evidence quality and formula fit. A DoseFit Score of 90 means this product's ingredient forms and doses are close to what was used in the studies behind this ranking - DoseRank weights each product ingredient.

Best ingredients

L-Leucine is the best supported ingredient signal for this outcome.

Dose matchedDoseFit 90

Scores reward products dosed inside or above the studied range, not just the right ingredient. Examples: Below range: L-Leucine 5 g vs 2000-5000 g.

Processed

5.1k

Available

5.1k

Ingredients

Brands

493

Coverage

100%

How to read the scores

What every metric means

Each score is 0–100. Higher is better for every metric below.

CompositeThe overall DoseRank score — a weighted blend of clinical strength, evidence, dose fit, trust and value.Higher is better

ClinicalHow strongly the formula's ingredients and doses match what clinical studies used for this outcome.Higher is better

EvidenceHow much published human research backs the formula's key ingredients for this outcome — both how many studies exist and how strong they are.Higher is better

ValueHow the price per serving compares with similar products for this outcome — 50 is the typical price, higher means better value for your money.Higher is better

TrustHow well customers rate this product, with extra weight given to ratings backed by a large number of reviews.Higher is better

PopularityHow strongly this product sells compared with the other ranked products for this outcome.Higher is better

This legend covers the scores on this page — for data sources, scoring weights, and limits, read the full methodology →

Not sure which is right for you?

Answer a few questions about your goals, habits, stack, and budget. Then, DoseRank will find the products that best match your needs based on your answers. It's free and only takes 60 seconds! No account is required.

Take 60-sec quiz

Get a personal report

A saved, shareable breakdown: your matched products, dose math, interaction flags to discuss with a clinician, and a price-tracked stack you can revisit.

Questions

Frequently asked

Each product gets a composite score blending clinical strength, evidence, dose fit, trust and value. The #1 on the DoseRank tab has the highest composite; the other tabs re-rank the same products by Value, Trust, or Popularity. Placement is never paid.

Increase muscle mass

What this outcome means

Who it's for

Building strengthLifters and athletes working to add lean size and power.

Age-related declineOlder adults losing muscle as the years add up.

Rebuilding after layoffComing back from injury, illness, or long time off training.

Stack buildersAlready taking supplements such as L-Leucine and want the dose right.

Evidence level

92Strong

Best ingredients

L-Leucine is the best supported ingredient signal for this outcome.

Dose matchedDoseFit 90

Scores reward products dosed inside or above the studied range, not just the right ingredient. Examples: Below range: L-Leucine 5 g vs 2000-5000 g.

Processed

5.1k

Available

5.1k

Ingredients

Brands

493

Coverage

100%

Relevant ingredients

Which ingredient types matter for muscle massOpen to see which ingredient types matter for muscle mass

4.4k products across 1 ingredient types — open to filter the ranking.

Use types to filter ranked products

Amino Acids & Derivatives

4.4k products

The building blocks of protein, taken singly for targeted effects – leucine for muscle, theanine for calm. Free-form versions absorb fast on an empty stomach.

Typical: ,

Top decision cards

Best products for muscle mass

Ranking by · Composite outcome score

Best overall — the composite outcome score.

Top pick · DoseRank

Why this ranks #1 for muscle mass

Nutricost, L-Leucine, Unflavored, 17.9 oz (500 g)

Nutricost$0.20 / serving4.7 · 363Available now

Why this ranks here

Evidence fitL-Leucine is the strongest evidence signal for this outcome.
Dose fitL-Leucine at 5 g sits below the studied 2000-5000 mg window.
Price / serving$0.20 per serving — low price tier for this outcome.
AvailabilityIn stock across major retailers; 99% availability confidence.
TrustMixed trust signals — ratings are positive but the base is limited.

Trade-offs

Trust signals sit below the other picks

The numbers

5 gBelow rangebelow the studied 2000-5000 mg window

Compare top 3 Product data Open at retailer

The rest of the ranking · DoseRank

Top 10 ranked products