#294 ‒ Peak athletic performance: How to measure it and how to train for it from the coach of the most elite athletes on earth | Olav Aleksander Bu

Episode Summary

Executive Summary: Peter Atiyah interviews endurance coach and exercise scientist Olav Alexander Bu about VO2 max, lactate, and performance physiology. They argue that velocity is the true race outcome, VO2 max is the best broad health marker but not always the best performance predictor, and that training should maximize specific work and accumulated oxygen demand while balancing sustainability, fueling, and efficiency.

Main Topics: Olav Bu’s background and performance philosophy (Priority: 4/5): Bu describes growing up on a farm in Norway, his engineering/technology mindset, and how he merged exercise physiology with real-world athlete monitoring to coach elite triathletes and other endurance athletes. ATP, oxygen, and the body as an engine (Priority: 5/5): The discussion frames human movement as energy conversion: substrates plus oxygen become ATP, with performance determined by how efficiently energy is converted into propulsion and how much is lost as heat. VO2 max as health marker vs performance metric (Priority: 5/5): Atiay and Bu agree VO2 max is a powerful integrative marker of health and longevity, but Bu emphasizes that in elite sport it is only one piece of the puzzle and can be outweighed by specificity, economy, and sustainable energy expenditure. Absolute vs relative VO2 max and body mass (Priority: 5/5): Bu argues that absolute VO2 max often matters more than relative VO2 max for flat or non-hilly racing, and that reducing body weight can sometimes lower both absolute and relative VO2 max rather than improve performance. Testing technology: lab carts vs portable VO2 systems (Priority: 4/5): They compare gold-standard lab metabolic carts with portable devices like the VO2 Master, discussing accuracy, practicality, and the value of frequent field testing in real training conditions. Lactate, LT1/LT2, and intensity control (Priority: 5/5): The conversation clarifies lactate as a concentration marker, distinguishes LT1, LT2, and MLSS, and explains why fixed lactate cutoffs are crude compared with individualized curves and context-specific thresholds. Training design, intervals, and specificity (Priority: 5/5): Bu argues that the best VO2-max session is not a single universal workout; instead, athletes should maximize accumulated high-quality work, use intervals that fit the event, and preserve consistency and recovery.

Key Arguments: Velocity is the ultimate performance metric; power, VO2, and lactate are only useful insofar as they help explain or improve speed. VO2 max is an exceptional integrator of health and work capacity, making it one of the best predictors of longevity, but it is not always the best predictor of race performance. Absolute VO2 max can be more relevant than relative VO2 max in many endurance events, especially flatter races where raw propulsion matters more than body-mass-normalized values. Reducing body weight does not automatically improve performance; in Bu’s athletes, weight loss sometimes reduced absolute VO2 max and even relative VO2 max. Low-intensity training is not “junk” if it is done mindfully; it can improve body awareness, efficiency, and technical execution. Portable metabolic devices can be accurate enough for practical athlete monitoring, especially when the goal is repeated field measurement rather than perfect lab precision. Lactate is useful but should be treated as a concentration marker influenced by hydration, fatigue, and protocol, not as a standalone truth about performance. For elite endurance athletes, the key training question is how much high-quality work and oxygen demand can be accumulated sustainably, not simply how high a single interval’s power is. Different race durations require different physiological priorities: Olympic-distance racing can support much higher VO2-max emphasis than Ironman racing. Microintervals, longer intervals, cadence, and torque all change the physiological stimulus; there is no single “golden” VO2-max workout.

Data Points: Christian Blumenfeldt / Gustav Iden VO2 max: ~90 mL/kg/min (relative) - Bu says his athletes typically test around this level when preparing for Olympic-distance racing. Christian Blumenfeldt / Gustav Iden VO2 max for Ironman specialization: below 80 mL/kg/min (relative) - Bu says VO2 max was intentionally reduced when they specialized for Ironman success. Christian Blumenfeldt absolute VO2 max: ~7.0 L/min - Bu cites this as an elite absolute oxygen consumption level. Olympic triathlon duration: ~1:40 to 1:45 - Atiay and Bu use this as the approximate race duration for world-class Olympic-distance triathlon. Ironman winning time: ~7:21 for Christian Blumenfeldt - Used to illustrate the extreme performance level and different energy demands of Ironman racing. Portable device vs lab VO2 difference: ~50 mL O2 - Bu says back-to-back testing between VO2 Master and lab systems typically differs by about this amount for elite athletes. Swimming flume example: ~25% less oxygen - An Olympic bronze medalist swam at the same speed as Christian while using nearly 1 liter less oxygen. RER threshold often cited in textbooks: >1.1 - Bu notes that some protocols require this for a VO2-max test to be considered valid, but he questions rigid use of the cutoff. Zone 2 lactate target: <2 mmol/L - Atiay describes his own endurance training zone as the highest sustainable power output below 2 mmol lactate. LT2 / MLSS example: ~80% of VO2 max - Bu estimates Ironman athletes may sit near this level at LT1/threshold-related intensities, depending on context. Energy conversion estimate: ~20 joules per mL O2 - Bu uses this simplification to explain how oxygen consumption maps to energy expenditure. Efficiency estimate: ~20% propulsive / 80% heat - Used to explain why most metabolic energy becomes heat rather than forward motion. Workouts discussed: 4-5 minute hill repeats; 5-minute intervals; 30-80 minute accumulated work blocks - Examples of interval structures used to target VO2 max and accumulated oxygen demand. Cadence example: ~95-100 rpm vs ~65-70 rpm - Atiay references classic cycling differences in cadence strategy and their physiological implications.

Pivotal Quotes: "“Velocity is king.”" — Peter Atiyah: Atiay summarizes the central performance principle: speed, not power or VO2 alone, determines race outcomes. "“Low intensity, medium intensity and high intensity should all be high quality.”" — Olav Alexander Bu: Bu argues against dismissing easy work as junk mileage when it is done with attention and purpose. "“The most important thing is exactly that you have a language and it does work for you.”" — Olav Alexander Bu: Bu closes by emphasizing that terminology matters less than shared understanding between coach and athlete.

Implications: Listeners should think of endurance training as a systems problem: improve VO2 max, but also economy, specificity, fueling, and sustainability. For athletes and coaches, frequent real-world measurement may outperform rigid textbook thresholds.