ABSTRACT
In the past many researchers have addressed the metabolic demands imposed on soccer players during competitive and friendly matches (Reilly and Thomas, 1976; Van Gool et al., 1988; Bangsbo et al., 1991; Pirnay et al., 1991). Less interest have been devoted to the soccer referee’s performance (Asami et al., 1988; Catterall et al., 1993) and the reports available in the international literature have been carried out employing indirect measurements (Catterall et al., 1993).
