The aim of this research was to determine the levels and structure of cardiac load via heart rate dynamic (HR) and movement activities of football referees during matches of the Premier League of Bosnia and Herzegovina and fitness testing. Additionally, the study aimed to investigate whether there are differences in the physical preparedness levels of Premier League referees and whether there are differences in running structures between referees in the Premier League of Bosnia and Herzegovina and those in the top European
leagues. Heart rate data during the SDS test suggested higher time spent in Zone 4 (81-90% HR max) compared to other zones. Heart rate data during matches mainly was in third and fourth intensity zones (p<0.001). Significantly higher heart rate load (HR load) was present during the SDS test compared to matches. High intensity runs war significantly lower compared to moderate and low intensity (p<0.05) and distances covered during matches were marginally lower compared to the observed in elite level league. Physical demands placed on football referees, particularly in the Premier League of Bosnia and Herzegovina, necessitate top-notch physical conditioning and overall health, and the research indicates that these referees exhibit physical characteristics similar to elite-level referees, with notable differences in intensity zones during matches and the SDS test, highlighting the suitability of the SDS test for evaluating their situational performance, while also highlighting the need for further improvement in their aerobic capacity.
Key words: high intensity, speed, matches, heart rate load