The Claim

Endurance athletes have a 30% longer diastolic filling period and 15% longer left ventricular ejection time at rest compared to sedentary controls, resulting in greater ventricular filling volume and higher stroke volume, which supports increased cardiac output during exercise.

Source: A race against time: timing constraints of cardiac filling and athletic performance.

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
76score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

How it works
1 study reviewed
In plain English

Endurance athletes have longer heart filling and pumping phases at rest than sedentary people, leading to more blood pumped per heartbeat and higher overall heart output during physical activity.

See the scientific wording

Endurance athletes exhibit a 30% longer diastolic filling period and 15% longer left ventricular ejection time at rest compared to sedentary controls, enabling greater ventricular filling volume and higher stroke volume, which supports superior cardiac output during exercise.

Why this might work

Endurance training makes the heart's main pumping chamber larger and more flexible, allowing it to fill with more blood between beats. The heart muscle also relaxes faster, so blood rushes in quickly during the early part of the filling phase. This lets the heart hold more blood before each pump, and it takes longer to eject that larger volume, so more blood leaves the heart with each beat. The result is a bigger amount of blood pumped per heartbeat, which supports higher blood flow during physical activity.

Verified mechanismbased on 1 study

What the research says

1 study

  1. Study: A race against time: timing constraints of cardiac filling and athletic performance.

    Endurance athletes' hearts take longer to relax and fill with blood between beats, even when they're resting. This lets their hearts pump more blood with each beat, which helps them perform better during intense exercise.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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