Cycling Biomechanics

Power, Endurance, and Peak Performance

Professional cycling—and particularly the Tour de France—represents one of the pinnacles of human physical performance. To understand how riders like Tadej Pogačar, Lance Armstrong, or Chris Froome were able to dominate this race, we need to delve into the biomechanics of cycling and analyze the power the human body can produce—and for how long.

1. Human Power Output on a Bicycle: Physiological Limits

Power in cycling is measured in watts (W) and more specifically in watts per kilogram of body weight (W/kg) to assess relative performance.

• Maximum instantaneous power: An elite sprinter can generate over 1,500 to 2,000 watts for a few seconds (5 to 15 seconds), which is an extreme demand on fast-twitch muscle fibers.

• Anaerobic threshold / FTP (Functional Threshold Power): This is the maximum power an athlete can sustain for about 60 minutes. Trained amateurs may reach 3 to 4 W/kg. Top Tour de France climbers can exceed 6 to 6.5 W/kg, especially for efforts lasting 20 to 40 minutes.

• Climbing power (20 to 40 minutes): This is where mountain stages are won. The best-documented performances are around 6.2 to 6.4 W/kg, which is close to what’s considered a natural human limit.

2. Estimated Power Outputs of Tour de France Winners

Here’s a comparative table of estimated power outputs for some Tour winners:

⚠️ Armstrong’s numbers must be viewed with caution. He admitted to using performance-enhancing drugs. At his peak, his W/kg may have exceeded 6.5 or even 6.7, which goes beyond what is generally accepted as naturally sustainable.

3. Where Do the Differences Come From? Biomechanical and Physiological Analysis

Key performance factors:

• VO₂max (maximal oxygen consumption): Pogačar and Froome both exceed 85 ml/min/kg, which is extraordinary. Armstrong reportedly reached similar levels.

• Biomechanical efficiency: This is the ratio between chemical energy expended (ATP) and mechanical energy produced. For top athletes, it ranges between 22 to 25%.

• Body weight and aerodynamics: Lighter climbers like Pogačar have an advantage on steep ascents. Froome, with his unique riding position, optimized aerodynamics even while climbing.

• Mental endurance and recovery: Over 21 stages, sustaining top performance daily also depends on hormonal, nutritional, and psychological regulation.

4. The Doping Debate and the "Limits of Nature"

Some past performances—particularly in the 1990s and early 2000s—raised serious suspicions due to power outputs seen as incompatible with human physiology. Generally, maintaining >6.2 W/kg for more than 40 minutes without pharmacological aid is viewed as highly unlikely.

Today, with the widespread use of power meters, frequent blood tests, and tighter oversight, performances appear more credible—even though skepticism occasionally remains.

Focus: The Unique Case of Miguel Indurain

Miguel Indurain, five-time winner of the Tour de France (1991–1995), is both a biomechanical anomaly and a model of efficiency. Unlike lighter climbers like Pogačar or Froome, Indurain stood 1.88 meters tall and weighed around 80 kg, which is unusually heavy for a Grand Tour rider, especially in the mountains.

Exceptional Physiological Capacities

Tests conducted on Indurain during his prime revealed remarkable figures:

• VO₂max: estimated at 88 to 92 ml/min/kg, a world record at the time.

• Lung capacity: over 7.5 liters (compared to 5–6 L for a trained adult).

• Resting heart rate: about 28 bpm, which is extraordinarily low.

• Absolute power output: over 500 watts during flat time trials, thanks to his size and aerodynamic position.

A Time-Trial Based Racing Style

Unlike other champions, Indurain didn’t win the Tour by attacking in the mountains. He would manage his effort on climbs and gain decisive advantages in the individual time trials, where he was nearly unbeatable.

His strategy was to:

• Limit losses in the high mountains with exceptional power management.

• Dominate flat stages with perfect aerodynamics and raw power that few could match.

Why This Profile No Longer Prevails

Today’s Tour routes are more mountainous and explosive, and the modern cycling culture favors attacking and maximizing watts per kilogram (W/kg). As such, a profile like Indurain’s would be at a disadvantage:

• His higher weight would be penalizing on steep climbs.

• Advances in equipment, data tracking, and race strategies now favor lighter, more versatile riders.

Miguel Indurain represents an older model of biomechanical excellence—built on absolute power, pacing, and energy conservation. His dominance was made possible by extraordinary physiology, a well-organized team, and an era where time trials carried more weight in the general classification. In today’s cycling landscape, his profile would be more suited to classics or time trials, but likely less dominant in a Tour de France that is now much more mountainous and aggressive.

Conclusion

Elite cycling performance is a finely tuned combination of genetics, training, biomechanics, and strategy. Riders like Tadej Pogačar and Chris Froome have approached the natural limits of human power output. While Lance Armstrong exceeded them artificially, modern performances appear to reflect a healthier balance—though the mark of 6 W/kg in mountain stages remains the signature of rare talent, discipline, and total body optimization.e du corps humain.