Fitness Testing

Measuring Real Change

Exercise testing in a laboratory is a great way to assess your current fitness level, determine optimal training zones and help determine the best type of training for you to meet your race goals. Nowadays the recreational and keen amateur athlete has greater access to these tests, which were once the preserve of elite and professional athletes. So is one VO2max test much like another? As with many things in life, the devil is in the detail.

If you are serious about using physiological testing to improve your results you need to be confident that the results are real. In other words, they are not a product of errors in the apparatus, procedures or protocols. If a test is not repeatable within acceptable standards of variance you may as well be comparing apples and oranges. So the number one most important factor in laboratory fitness testing is quality control, the ability to reproduce accurate results that allow comparison between tests.

As an athlete looking to improve your performance you don’t want, or need to be an expert in laboratory QC procedures but you do want to be reassured that the lab you use is.


Some of the key areas for QC when conducting performance testing include:

  • The accuracy of the equipment being used. High-end breath-by-breath gas analysers have accuracy in the region of 0.05% volume and the volume measuring device has an accuracy of 3%. This means VO2 and VCO2 values are accurate to within 3%.
  • The precision of the equipment - Quality control measures generate reproducible results to allow an assessment of the true physiological adaption(s) to training; rather than being a change generated from environmental differences or system errors. This highlights the importance to be re-tested using the same device – the accuracy of the system will be the same, the precision will be dependent on those stringent QC’s.
  • How often is the equipment calibrated for volume and gas analysis? Pre-test verifications check the hardware/software as well as correcting for any change in the environment, which minimizes variable errors and increases precision. This means a result from today can be compared to the one in three, six, 12 months time. Linearity checks are performed to ensure the analyzer signal is accurate across the full working range rather than at only two fixed points.
  • How often are biological controls used to check the physiological range of the gas analysers. This involves putting the same person/people through a standard test to ensure their biological data is consistent over time. This might be done weekly.
  • How is data interpretation done? Automatically by the software, or manually by a trained physiologist? 

There is no doubt about the great benefits that can be derived from laboratory fitness testing but ultimately it is down to the lab’s QC procedures as to the ultimate usefulness of the results.

The ION Performance Centre offers a range of physiological tests suitable for athletes of any standard.
Find out about our QC procedures here.  


Tags: VO2max, physiological testing, performance

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