Making Sense of the Data with Dr. Marco Altini

About this episode

Steve House interviews Dr. Marco Altini about heart rate variability and its implications for endurance athletes.

Steve House sits down with Dr. Marco Altini — data scientist, physiologist, and founder of HRV4Training — for a deep-dive into one of the most misunderstood tools in endurance athletics: heart rate variability. With over 50 peer-reviewed papers to his name, Dr. Altini brings rare scientific rigor to a space crowded with oversimplified wearable metrics. The conversation opens by challenging the industry's obsession with single-number readiness scores, which Dr. Altini argues dilute nuanced physiological signals into deterministic assumptions that don't reflect the complexity of the human body. The episode unpacks the fundamentals of HRV — what it actually measures, why morning is the optimal measurement window for endurance athletes, and how to interpret it as a marker of stress response rather than performance capacity. Steve and Marco also cover hardware accuracy across chest straps, optical sensors, and phone cameras; HRV research at altitude; and the broader question of how biometric data should support — not replace — the athlete's own sense of feel. Special Offer to Listeners: Receive free four week samples of our most popular training plans, visit uphillathlete.com/letsgo…

People in this episode

Host: Steve House

Guest: Dr. Marco Altini

Topics covered

• heart rate variability
• endurance athletics
• physiological signals
• biometric data
• training metrics

Keywords

• heart rate variability
• HRV
• endurance training
• physiology
• biometric data
• wearable metrics
• stress response

Sponsors

Uphill Athlete

Mentioned in this episode

Organizations: HRV4Training

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