v1

mechanistic

Analysis v1

Strong Opposition

Muscle growth mainly happens because the tiny fibers that make your muscles contract get bigger and stronger; the fluid part of the muscle increases too, but only as a side effect and not on its own.

1

Pro

39

Against

Evidence from Studies

Supporting (1)

1

Community contributions welcome

1

Load-induced human skeletal muscle hypertrophy: Mechanisms, myths, and misconceptions

Narrative Review

2025 Nov 21

The study says that muscle growth mainly happens because the parts that make muscles contract get bigger, not because of fluid or other non-contractile stuff increasing on its own.

Contradicting (1)

39

Community contributions welcome

39

Muscle fiber hypertrophy in response to 6 weeks of high-volume resistance training in trained young men is largely attributed to sarcoplasmic hypertrophy

Cohort Study

Human

2019

The study found that muscles grew bigger not because of more contractile proteins like actin and myosin, but because of an increase in fluid and energy-related proteins inside the muscle cells.

Gold Standard Evidence Needed

According to GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this specific claim, ordered from strongest to weakest evidence.

Similar Assertions

When muscles get bigger from working out, it’s not really because they’re storing more water or sugar—those changes don’t last or help much. What really matters is that the actual muscle fibers grow thicker.

1

0

86%

When muscles get bigger over time, it’s not because the non-working parts inside them swell up—it’s because the actual muscle fibers that do the contracting grow more, and that’s what really matters.

1

0

86%

When muscles get bigger over time, it’s not because the non-working parts inside them swell up—it’s because the actual muscle fibers that do the work grow more, and that’s what really matters.

1

0

86%

When muscles get bigger over time, it’s not because the non-working parts inside them swell up—it’s because the actual muscle fibers that do the work grow more, and that’s what really matters for lasting muscle growth.

1

0

86%

When muscles get bigger over time, it’s not because they’re filling up with water or sugar stores—it’s because the actual muscle fibers are adding more contractile proteins.

1

0

85%