Acute effect of individual interaction space on physical and physiological demand in young soccer players

The aim was to analyze the effect of age on the physical and physiological demands of small games with different individual interaction spaces. Thirty players under-12 (U12: n=10; age, 11.2 +/-0.8 years; height, 145.4 +/-6.4 cm; body mass, 37.5 +/-3.9 kg), under-14 (U14: n=10; age, 13.5 +/-0.6 years; height, 163.7 v 5.9 cm; body mass, 51.5 +/-6.2 kg) and under-16 (U16: n=10; age, 15.8 +/-0.4 years; height, 172.8 +/-7.3 cm; body mass, 61.2 +/-9.3 kg) participated in the study. Sided games (SG) of 5 vs 5 with individual interaction space (IIS) small = 50 m2 (SGs), medium = 100 m2 (SGm) and large = 150 m2 (SGl) were performed. The physical demand was obtained with GPS recording the total distance, the neuromuscular load and the distance in speed ranges. The physiological load was obtained with 3 intensity zones from the maximum heart rate (HRmax): Z1 < 80% HRmax, Z2 = 80-90% HRmax and Z3 > 90% HRmax. The U12 covered significantly less distance than U14 (p < 0.05) and the U16 (p < 0.05) in all formats. In SGm the distance at high speed was significantly greater in U16 than in U14 (p = 0.000) and U12 (p = 0.000). In U12, a higher IIS corresponds to a significant increase in Z3 (SGs vs SGm: p = 0.001; SGs vs SGl: p = 0.001; SGm vs SGl: p = 0.000). The IIS causes a different stimulus in soccer players according to age.