Validity and Reliability in Exercise Testing
When using an exercise test to measure some aspect of physical capacity, it is important to consider whether the test is both valid and reliable. To be valid, a test needs to measure what you are actually trying to measure. For example, to measure aerobic fitness an accepted outcome to record is VO2 peak (maximal oxygen consumption). When choosing a test to measure aerobic fitness, it would be best practice to select a test that measures VO2 peak such as a graded exercise test which records actual oxygen consumption or calculates it based off exercise heart rate rather than for example, how far one can walk in six minutes (6 minute walk distance - derived from a 6 minute walk test). To be reliable, a test must be repeatable - you need to be able to control the variables that can affect results as best you can. For example, if you perform an aerobic test in an extremely hot environment on one occasion, and in a cooler environment on a separate occasion, the results may not be...