Physiologically Speaking Is Zone 2 Training Optimal for Mitochondrial Health? My Interview with Kristi Storoschuk
Jul 24, 2025
In this engaging discussion, Kristi Storoschuk, a PhD candidate in muscle physiology at Queen’s University, shares her insights on mitochondrial health and exercise. She critically assesses the popular claims surrounding Zone 2 training, revealing limited evidence for its benefits over high-intensity interval training. Kristi explores the 80-20 training principle, challenging misconceptions about workout sustainability and its implications for overall fitness. Tune in for a fresh take on optimizing exercise strategies tailored to individual needs!
AI Snips
Chapters
Transcript
Episode notes
Zone 2 Lacks Strong Direct Evidence
- There are very few controlled studies that actually prescribe 'zone 2' as defined in popular media.
- Kristi found limited and mixed evidence that zone 2 uniquely drives mitochondrial adaptations compared with higher intensities.
80/20 Is An Observational Artifact
- The popular 80/20 pattern in elite athletes is observational, not prescriptive, and stems from huge training volumes.
- Extrapolating that ratio to the general population is likely inappropriate because elites still do substantial high-intensity work.
Prioritize Volume Above Zone 2
- Prioritize accumulating recoverable exercise volume above zone 2 before adding low-intensity zone-2 sessions.
- Aim for higher intensities (heavy domain, zone 3–4) where tolerable to maximize adaptation and health gains.