Abstract
The goal of this open-label, placebo-controlled, dosage escalation study is to learn about the safety of a Cannabis/Hemp Isolate Extract in normal healthy adults engaged in elite contact sport competition. The main question it aims to answer is: • Are cannabis/hemp-based products with high CBD safe, well-tolerated and without adverse physiological and psychological dysfunction, when administered on a daily basis? Participants will: * be given CBD and a placebo. The placebo will be taken for 2 weeks prior to starting the CBD. Participants will start on a low dose of CBD, beginning at 5 mg CBD/kg body mass, which will be increased by 5 mg/kg every 2-weeks until 30 mg CBD/kg body mass is taken; * have blood samples taken to analyse how much CBD is used in the body and for how long it lasts in the body (pharmacokinetics and pharmacodynamics); * have saliva samples collected for genetic analysis; * undergo testing sessions, which will include psychological and health questionnaires, equipment to record signals from the brain and heart, and safety laboratory tests.