Summary
Both high-intensity interval training (HIIT) and moderate continuous training improve HRV, but through different pathways. HIIT may produce faster initial gains; moderate training builds more sustainable improvements.
Methods
Randomized trials comparing HIIT vs moderate intensity continuous training (MICT)
Key Findings
- Both modalities improved resting HRV after 8-12 weeks
- HIIT showed faster initial HRV improvements
- MICT produced more stable, sustained HRV gains
- Combination training may be optimal
Limitations
Individual response varies; recovery capacity matters
What This Means for You
Don't assume you need HIIT to improve HRV. Moderate, consistent cardio training is highly effective. If you do HIIT, ensure adequate recovery— overreaching will suppress HRV despite the training benefits.
Source
Read the original paper in Sports Medicine ↗
Added to HRV Zone: 2025-01-09