English premier league referees covered less total distance during the
2
nd half of the match (5790±416 vs. 5832±389m, p=0.04). In the study of D’Ottavio
and Castagna (2001b), average match distance covered by Italian serie A and B
referees was 11376 1600 m (7818-13063) and no overall differences were observed
between halves (p > 0.05). Nevertheless less distances were covered running backward
and side-wards during the 2nd half compared to the 1st half (p < 0.05). In their
study, referees, on average, covered 41.7% of the whole match distance at speeds
faster than 13.1 km x h(-1). Heart rates attained 89.1% of the estimated maximal
over the duration of a full game and no difference was observed between halves (p
= 0.72).