PMID 37309084

Research
All papers

Attenuated pulsatile transition to the cerebral vasculature during high-intensity interval exercise in young healthy men

Sugawara J, Hashimoto T, Tsukamoto H, Secher NH, Ogoh S

Question

Does the arterial system attenuate pulsatile pressure and flow transmission to the cerebral vasculature during high-intensity interval exercise?

Summary

Fourteen healthy young men completed semi-recumbent cycling intervals while researchers measured invasive arterial pressure and middle cerebral artery blood velocity. Cerebral pulsatile transmission was attenuated during exercise, suggesting a protective hemodynamic response, but the study was acute, male-only, and mechanistic.

Methodology

  • Healthy young men.
  • 14 participants.
  • Cycle ergometer.
  • Work intervals: 4 min at 80-90% Wmax.
  • Recovery: 3 min active rest at 50-60% Wmax.
  • Intensity: 80-90% maximal workload.
  • 25 min for four bouts plus active rests.
  • Single session.
  • Acute.
  • Acute mechanistic laboratory study
  • Pulsatile transition, Transfer gain, Hemodynamics, and Safety were tracked.

Outcomes

Pulsatile transition

Aortic-to-cerebral pulsatile transition decreased during HIIE.

Reduced throughout bouts, p<0.05 vs baseline.

Improved

Transfer gain

Transfer function gain decreased and phase increased during HIIE.

Both p<0.0001.

Improved

CVCi

Cerebrovascular conductance index did not significantly change.

p=0.296.

No clear change

Tolerability

All completed, but four participants reduced workload in later bouts.

10 maintained workload; 4 requested reduction.

Mixed

Insights

  • Mechanistic data suggest healthy young men attenuate cerebral pulsatile transmission during HIIE.
  • Repeated 4-min high-intensity bouts may require down-adjustment for some users.

Limitations

  • Healthy young men only.
  • Acute mechanistic study.
  • Aortic pressure estimated rather than directly catheterized at the heart outlet.
  • TCD measures velocity, not direct cerebral blood flow.
  • Modelflow hemodynamics were indirect estimates.

Safety

  • No adverse events were reported.
  • Four healthy participants requested workload reduction during later high-intensity bouts; invasive arterial and cerebral blood-flow monitoring was used.