the short answer
A personal trainer liability waiver covers risk and liability, a PAR-Q health screen checks whether it is safe to start exercising, and informed consent explains what the coaching involves and its limits. Online coaches collect all three at intake, route any red flag to a doctor for clearance first, and store the dated, signed forms per client. In Coachway you build these as required drag-and-drop intake forms, so no client can be marked active before they are screened.
This article is general information for coaches, not legal or medical advice. Waiver wording, health screening duties, and consent requirements vary by country and state, and they do not replace talking to a qualified attorney, your insurer, or a medical professional about your own situation.