Physical demands in a small-sided soccer game: a comparison between arbitrary and individualized speed and metabolic power thresholds

Background: This study compared the arbitrary and individualized speed and metabolic power (P-met) intensity thresholds in a small-sided game (SSG) regarding: 1) distance covered; 2) variations of the physical parameters during the SSG; and 3) associations with physical fitness.Methods: Twenty-four amateur soccer players (age: 20.0 +/- 1.7 years; height: 176.4 +/- 4.2 cm; body mass: 67.6 +/- 3.2 kg), after being tested for maximal aerobic speed (MAS) and maximal sprinting speed (MSS), participated in a SSG in a separate session and were monitored with global positioning systems (GPS). The distance covered was classified into three intensity zones for each variable (speed and P-met) using arbitrary and individualized zones based on MAS.Results: There were differences in the distance covered between methods in zones 1 and 2 for both speed and P-met(P<0.001), and in zone 3 only for P-met (P<0.001). There were no variations in any variable analyzed during the SSG. MAS was positively correlated with the distance covered in zone 3 in the arbitrary speed (r=0.67; P<0.001) and P-met (r=0.60; P<0.01). MSS was negatively correlated with the distance covered in zone 3 in the individualized speed (r=-0.49; P<0.05) and P-met (r=-0.48; P<0.05).Conclusions: This study showed that arbitrary and individualized provide different information. While the individualized method could be used to monitor physical demands, the arbitrary could be used to assess running physical performance.