Futsal Intermittent Endurance Test (FIET)

The FIET consisted of shuttle-run bouts of 45 m (i.e., 3 × 15 m) performed at progressive speeds until voluntary exhaustion (Castagna and Barbero Álvarez, 2010). Every 45 m, players were allowed to actively rest for 10 s. After each 8 × 45 m bout, players passively rested for 30 s. The starting velocity was set at 9.0 km/h with speed increments of 0.33 km/h during the first 9 × 45 m bouts. After 9 × 45 m bouts, the increment changed to 0.20 km/h every 45 m until exhaustion. The speed was controlled by prerecorded audio cues (Speaker, Satellite, Taiwan). The test was finished when participants did not reach the front line in time with the beeps for 2 consecutive repetitions. The peak speed (i.e., PS_FIET) reached at the end of the test by the athletes was reported as the performance criterion for the FIET.