Research

Mixed

Increases in lean mass (hypertrophy) are not significantly associated with improvements in muscle strength, endurance, or power in resistance-trained young males, indicating that functional adaptations occur independently of muscle size gains.

If you are a trained individual, do not assume that your strength gains are limited by your muscle size. You can improve your strength, power, and endurance significantly without necessarily gaining large amounts of lean mass. Focus on technical proficiency and neural adaptation (e.g., heavy loads, specific power drills) rather than just volume for hypertrophy, as these functional improvements can occur independently of muscle growth.

GoodRefutesHIGH confidence
Changes in muscle strength, endurance and power adaptation responses following 16 weeks of either CT or RT with different high protein intakes were not associated with changes in lean mass in resistance-trained young males. These findings indicate that muscle hypertrophy has a small, or negligible, contributory role in promoting functional adaptations with RT or CT, at least over a 16-week period.
Reza Bagheri et al. · Frontiers in Nutrition · 2024

Why this rating

Randomized controlled trial with 48 participants, rigorous DXA measurements, and statistical controls, though limited to young, resistance-trained males.

Source

Association between changes in lean mass, muscle strength, endurance, and power following resistance or concurrent training with differing high protein diets in resistance-trained young males

Reza Bagheri et al. · Frontiers in Nutrition · 2024

DOI 10.3389/fnut.2024.1439037

rct · n=48Cited 4×
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DOI resolved against Crossref · corpus check 2026-06-10

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