The document discusses the importance of assessing fitness levels through collecting both quantitative and qualitative data. It notes that fitness assessment allows individuals to identify strengths and weaknesses, providing a baseline and allowing monitoring of development. There are two main ways to assess fitness: directly within an activity, and outwith using standardized tests. Data should be accurate, relevant, valid, reliable and objective to be useful for informed decision making and performance improvement. The document outlines various data collection methods that can be used both within and outside of activities.