Internal and external load during 8 v 8, 5 v 5 and 3 v 3 in Chinese elite youth male football players

Abstract

Aim to investigate internal and external load in three different game formats (8v8, 5v5, 3v3 with 80 m² per player) of small-sided games (SSG) in Chinese elite youth football players. Twenty-nine elite male football players (age: 18.3 ± 0.5 years (mean ± SD), height: 175 ± 6 cm, weight: 65.5 ± 6.3 kg) participated in randomized order in the three formats. Each session consisted of 20 min: 3v3 on a 24×20-m pitch, 5v5 on a 32×25-m pitch, or 8v8 on a 40×32-m pitch all equalling 80 m² per player. Each player was recorded once in each format. Using GPS-units and heart rate belts and blood lactate measured the two kinds of load. 8–10% higher total distance (P < 0.01) was observed in 8 v8 and 5v5 compared with 3v3 (1627 ± 240 and 1595 ± 243 m vs. 1477 ± 179 m, ES = 0.55–0.71). Higher distance (P < 0.001) was covered with high speed running (HSR: > 14 km/h) in 8v8 and 5v5 than 3v3 (154 ± 94 m and 133 ± 59 m vs. 77 ± 35, ES = 1.09–1.15), whereas very high speed running distance (> 21 km/h) was higher (P < 0.01) in 8v8 than 5 v 5 and 3 v 3 (15.2 ± 19.5 vs. 5.3 ± 6.7 and 1.0 ± 0.4 m, ES = 0.69–1.03) and in 5 v 5 than 3 v 3. No difference was found between game formats in the number of intense accelerations nor intense decelerations. Blood lactate (3.5 ± 2.3 vs. 2.8 ± 1.9 vs. 2.4 ± 1.5 mmol·L ^-1, P = 0.201) and mean heart rate (155 ± 21 vs. 160 ± 11 vs. 157 ± 17 bpm, P = 0.254) was not different between 8v8, 5v5 and 3v3 game formats. Distance covered in total and in highest speed zones was higher in SSG formats with more players, which, however, did not lead to differences in internal load measured by heart rate and blood lactate.