One common practice in talent development environments during the investment years (age 16+) and elite sport, in general, is the use of physiological testing of the athletes’ physical determinants of performance. In this article, the regime of controlling and monitoring athletes’ bodies for elite sport production through physiological testing will be examined. To this end, we explored athletes’ experiences of what has been done and why physiological tests are carried out the way they are to understand the practice of physiological testing in relation to athlete development. The material in this study is based on interviews with adult elite sport athletes (four group interviews with eight individual athletes in three different sports, four male and four female, and individual interviews with twelve female and five male football players). Schatzki's and Reckwitz's theorizing on social practices, together with Dewey's theorizing on learning from experience, are used to explore and illuminate the practice of physiological testing and what learning is enabled and constrained within that practice. The findings show that the meaning and significance of physiological testing for athletic development relates to how the tests are followed up and talked through with the athletes. The analysis shows that there exists a form of sport-wide commonality where the same understandings, rules or ends—irrespective of which sport is concerned—govern coaches’ and athletes’ behavior regarding physiological tests. The physiological testing practice articulates action intelligibility through rules and structures which emphasizes tests as isolated quantified indicators of physical status. The use of physiological tests as a part of learning or as a means for athlete development can therefore be questioned.