We invite testers from iWorx , Adinstruments, g.tec medical, Biopac, Quinton standard 3-leads Q-tel RMS and other manufacturers of high quality HRM devices to find out which is the most accurate optical sports watch, and to compete with Rob ter Horst in this competition to be the first to know it

If someone can publish a scientific paper which shows us that one of these sports watches is highly accurate and can be used for clinical and research applications, we will go back to sports watches to choose those as our research equipment.