The Claim
Twelve weeks of resistance training increases the number of capillaries per muscle fiber in both type I and type II muscle fibers of the biceps brachii in college-aged men, with measured increases from 4.9 ± 0.6 to 5.5 ± 0.7 in type I fibers and from 5.1 ± 0.8 to 6.2 ± 0.7 in type II fibers, while capillaries per unit area remain unchanged, suggesting that capillary growth is proportional to muscle fiber hypertrophy.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
Lifting weights for three months increases the number of tiny blood vessels in arm muscles of young men, and the growth keeps up with how much the muscle fibers get bigger.
See the scientific wording
Twelve weeks of resistance training increases capillaries per muscle fiber in both type I and type II fibers of the biceps brachii in college men, with type I increasing from 4.9 ± 0.6 to 5.5 ± 0.7 and type II from 5.1 ± 0.8 to 6.2 ± 0.7, while capillaries per unit area remain unchanged, indicating capillary growth is proportional to fiber hypertrophy.
What the research says
1 studyThe study looked at college men doing 12 weeks of weight training and found their muscle fibers got bigger and had more capillaries around them, just like the claim says. The number of capillaries per area didn’t change, meaning the blood supply grew along with the muscle.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.