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Image by Brian Erickson



Lactate testing

‘Assessing your aerobic and anaerobic thresholds is important for every mountain athlete because that is how you will correctly define your training intensities for different workouts’

-Kilian Jornet, Scott Johnston & Steve House

The Uphill Athlete 


The benefits of lactate testing:

-Determine appropriate training intensities, by establishing intensity zones

-Determine whether or not an athlete has aerobic deficiency syndrome

-Allow for future checks on progress in aerobic capacity development

-Assess relative composition of muscle fibre types


Step test

-This allows us to identify an athlete’s lactate threshold pace & heart rate, and to establish training zones


Aerobic threshold test

-This allows us to identify the aerobic threshold pace & heart rate, and to determine whether an athlete is aerobically deficient


Relative muscle fibre composition test

-This test allows us to determine whether an athlete's muscle fibre type is predominantly fast twitch, slow twitch, and inform training decisions on the basis of this result.

How we do it: the athlete runs at a maximal effort for 1-2 minutes, and we measure blood lactate levels upon completion of the effort and intermittently for the next 20 minutes, to identify the peak blood lactate concentration.  A high peak value indicates that the athlete is relatively fast-twitch dominant, and a low lactate peak value suggests dominance of slow-twitch muscle fibres.

What it means for your training:  Muscle fibre composition can have huge implications for training design.  To name just a few examples, slow-twitch runners can maintain peak fitness for longer, can burn fat more effectively, and are good at using lactate as a fuel.  In contrast, fast-twitch runners must keep easy runs very easy, burn a relatively greater amount of carbohydrate when training, have a better turn of speed (e.g. kick at the end of a race) and can benefit more from active (jog) recovery during interval sessions.

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