The Claim
Total myocardial blood flow, calculated as myocardial blood flow multiplied by left ventricular mass, is higher in endurance-trained men compared to untrained men, with the difference attributed to increased cardiac size rather than enhanced tissue-level perfusion.
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.
Endurance-trained men have higher total blood flow to the heart due to larger heart size, not because more blood flows through each unit of heart tissue.
See the scientific wording
Total myocardial blood flow (MBF multiplied by left ventricular mass) tends to be higher in endurance-trained men (1398 ± 585 mL/min) than in untrained men (972 ± 327 mL/min, p = 0.12), suggesting that increased cardiac size, not tissue-level perfusion, supports greater cardiac output.
The heart muscle grows larger in endurance-trained individuals, so even though blood flow per gram of tissue stays the same, the total amount of blood flowing through the entire heart increases because there is more tissue to supply.
What the research says
1 studyStudy: Estimated exercise‐induced maximal myocardial blood flow in untrained and endurance‐trained men
Athletes' hearts are bigger, so even though each part of the heart gets the same amount of blood as in non-athletes, the whole heart gets more blood because it's larger. This lets athletes pump more blood overall.
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.