Here's a pre-recorded version of my talk from the STORK Summit 2022 (as I was on holiday during the first day when it was scheduled). The original abstract is also below: **Abstract** What to expect from interventions in sport and exercise is very rarely a precise affair. Often the best we can do is make potential directional predictions due to some vague verbal theory regarding the proposed mechanism of action for the intervention. Rarely are we able to a priori deduce what to expect as a point or even interval prediction. This hampers our ability to design and conduct informative trials of interventions, for not knowing what effects we should be planning to expect from them impacts our knowledge of the power/precision to detect them. However, the development of more precise formal theories/models might aid us in this endeavour. A formal theory or model provides what Paul Meehl dubbed the Spielraum (German word for “action play,” “play/game space,” “field,” “range,” “scope,” “elbow room”); that is to say, an expectation of effects assuming the model were a true description of the data generating process. While some areas of sport and exercise science do have a history of formal theories/models, to the best of our knowledge, formal dose-response models are rarely if ever employed in sport and exercise science to deduce the expected effects that might be used to inform typical randomised trial designs for the evaluation of interventions. Yet, in the field of clinical drug development this is far more common where phase II trials explore mathematical representation of the underlying dose-response relationships. These models can then be used to simulate populations of patients undergoing comparative phase III trials i.e., confirmatory studies comparing different doses under randomised conditions. This session will discuss processes for generating formal models for intervention effects, and demonstrate how they can aid in study planning for intervention evaluation. In light of this, using some real-world examples we will discuss some of the possible repercussions of this approach and how we might as a field take steps forward in their light… or indeed, whether we should even bother.