The aim of this study was to examine the possible association between Yo-Yo intermittent recovery test level 1 performance (distance covered, Yo-Yo IR1) and match activities (direct validity) in young male team handball players. Eighteen young male players (age 14.3 +/- 0.5 years, body mass 64 +/- 28.7 kg, height 174 +/- 6 cm, body fat 11.2 +/- 3.9%) took part in this study. Players' match activities were videotaped during an experimental tournament (6 games/player) and analyzed using a computerized system. Games and Yo-Yo IR1 heart rates (HRs) (short-range telemetry, HR) and blood lactate concentrations ([la]b) were assessed throughout and at selected times of the games, respectively. Peak Yo-Yo IR1 HR was assumed as representative of individual maximal HR (HRmax). Mean and peak game HRs were 174 +/- 3 and 198 +/- 2 b.min, which corresponded to 87 and 99% of HRmax, respectively. Yo-Yo IR1 performance (1,831 +/- 373 m) was significantly related (r = 0.88, p < 0.01) to total game distance (1,921 +/- 325 m). Post-game (9.2 +/- 2.3 mmol.L) and Yo-Yo IR1 (8.8 +/- 1.6 mmol.L) [la]b were significantly related (r = 0.51, p < 0.05). These findings demonstrated the direct validity of Yo-Yo IR1. Consequently, Yo-Yo IR1 test may be considered as a team handball test relevant for the assessment of intermittent high-intensity endurance in young male team handball players.