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"Practice makes perfect" except when you practice imperfectly

Improved muscular efficiency displayed as Tour de France champion matures

Edward F. Coyle


This case describes the physiological maturation from ages 21 to 28 yr of the bicyclist who has now become the six-time consecutive Grand Champion of the Tour de France, at ages 27–32 yr. Maximal oxygen uptake (O2 max) in the trained state remained at ~6 l/min, lean body weight remained at ~70 kg, and maximal heart rate declined from 207 to 200 beats/min. Blood lactate threshold was typical of competitive cyclists in that it occurred at 76–85% O2 max, yet maximal blood lactate concentration was remarkably low in the trained state. It appears that an 8% improvement in muscular efficiency and thus power production when cycling at a given oxygen uptake (O2) is the characteristic that improved most as this athlete matured from ages 21 to 28 yr. It is noteworthy that at age 25 yr, this champion developed advanced cancer, requiring surgeries and chemotherapy. During the months leading up to each of his Tour de France victories, he reduced body weight and body fat by 4–7 kg (i.e., ~7%). Therefore, over the 7-yr period, an improvement in muscular efficiency and reduced body fat contributed equally to a remarkable 18% improvement in his steady-state power per kilogram body weight when cycling at a given O2 (e.g., 5 l/min). It is hypothesized that the improved muscular efficiency probably reflects changes in muscle myosin type stimulated from years of training intensely for 3–6 h on most days.

The entire manuscript can be viewed and dowloaded here: J Appl Physiol 98: 2191-2196, 2005. First published March 17, 2005; doi:10.1152/japplphysiol.00216.2005

COMMENT: This study looks at Tour de France Lance Armstong and physiolgic changes that occurred over the years leading to his first TDF win. This is a most interesting article looking at some of the physiologic changes that occurred to Lance Armstrong over a seven year period, to the point of becoming the dominant cyclist in the world. The most interesting finding is the only substantial change is he improved his cycling efficiency of just under 10%. When combined with his reduced body weight this resulted in an 18% improvement in steady state power per kilogram body weight. We believe that change alone, when applied to someone who is already at world class level, can explain his dominance in the Tour de France that occurred at the end of this period without the need to invoke any performance enhancing drug use (drugs cannot cause such changes). Unfortunately, despite Coyle recognizing this huge finding Coyle only has a mediocre analysis as to how one might improved pedaling efficiency so substantially. Coyle simply assumes this improvement came about because Lance somehow changed his muscle fibre type to more slow twitch muscles without any discussion as to other potential methods (see the Luttrell study above). Regardless of how Lance managed to improve his efficiency, it is important to understand that improving cycling efficiency can improve performance IN EVERYONE! As clearly demonstrated in the Luttrell study above, PowerCranks can improve cycling efficiency in trained cyclists.