Change of Direction Density: A Novel Consideration of Consecutive Changes of Direction in Elite Youth Soccer.

Morgan, OJ, Drust, B, Ade, JD, and Robinson, MA. Change of direction density: A novel consideration of consecutive changes of direction in elite youth soccer. J Strength Cond Res 39(8): e1010-e1016, 2025-This study aimed to characterize change of directions (CODs) based on density (number of CODs within 10 seconds), locomotor activity (walk, jog, stride, and sprint), and movement direction pre- and post-COD (forwards, sideways, and backwards), relative to playing position. In total, 24 elite male English Premier League academy soccer players (mean ± SD ; age: 19.0 ± 1.9 years, height: 179.9 ± 7.0 cm and body mass: 71.9 ± 6.4 kg) were individually filmed during 10 competitive matches. In total, 7,399 CODs were observed. Level of significance was p ≤ 0.05. An average of 84 ± 23 multiple COD events per player, per game occurred with no significant difference between position. Six CODs within 10 seconds were the average maximum density across positions (1.4 ± 1.2), with 9 CODs within 10 seconds being the maximum observed. Overall, 94% of multiple COD events were 2, 3, and 4 CODs within 10 seconds collectively, and were each performed significantly more than all other density categories (5-9 CODs in 10 seconds) ( p < 0.001). Jogging and striding pre- and post-COD were the most common locomotor activities ( p < 0.05). Change of directions were rarely surrounded by sprinting (1.4 ± 1.4) with <1% of total CODs with a sprint (pre and post) with approximately half of CODs (53%) occurring in a forward movement pre- and post-COD. Change of directions seem to be performed as multiple events, in multiple directions, at mostly submaximal locomotor activities, with some positional differences for movement direction and locomotor activity pre- and post-COD. These data provide valuable guidance for practitioners for testing, conditioning, and rehabilitating soccer players.