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Runner's performance evaluation - Part 3: Energy expenditure during running.

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This is the third part (the first was about VO2max, while the second was about the energy expenditure during rest) of a journey into the evaluation of the runner's performance, made possible with the big support of Mark Henninger (himaxx Centre for Altitude Training - Berlin, Germany), that provided the ergospirometer, the treadmill, the hypoxic chamber and his knowledge for the tests. Thanks Mark!
In terms of total energy expenditure is it more expensive running a 10 km race at 10 km/h or at 20 km/h? If we don't consider the air friction component and if the race is run without any pace variation (steady state), the answer is: the total energy requirement is approximately the same!

The reason lies in the linear relationship between oxygen consumption and running speed. As a rule of thumb, during horizontal running the energy cost is about 1 kCal/kg/km. Thus, the energy cost of running 10 km for a 70 kg individual averages 700 kCal, regardless of running speed.

Having an ergos…

Runner's performance evaluation - Part 2: Carbs, Fats and Proteins as Energy for living.

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This is the second part (the first was about VO2max) of a journey into the evaluation of the runner's performance, made possible with the big support of Mark Henninger (himaxx Centre for Altitude Training - Berlin, Germany), that provided the ergospirometer, the treadmill, the hypoxic chamber and his knowledge for the tests. Thanks Mark!
During exercise the whole-body energy requirement increases 20 to 30 times above resting levels, but what are the relative contribution of Carbohydrates, Lipids and Proteins in the different energy transfer systems?
First of all, we need to define the above-mentioned "resting levels": the BMR (Basal Metabolic Rate) is the amount of energy expended daily by humans and other animals to sustain vital functions in the waking state. Under controlled laboratory conditions, after at least 3 hours from the last light meal and without prior physical activity, the RMR (Resting Metabolic Rate) can be measured. The TDEE (Total Daily Energy Expenditu…