Influence of Relative Pitch Area (RPA) on the Physical Demands Across Late-Stage Age Categories in Elite Academy Soccer

Abstract

Introduction & Purpose: Small-sided games (SSGs) are widely used in soccer training to recreate the physical, technical and tactical demands of official matches within controlled environments (Morgans et al., 2014). Manipulating pitch size, player numbers, and rules, allows SSGs to develop these demands, especially physical performance (Bujalance-Moreno et al., 2019). The interaction of pitch size and player numbers can be quantified through the relative pitch area (RPA; m²*player^-1) (Hill-Haas et al., 2011; Olthof et al., 2019). A larger RPA elicits greater total distance, high-speed running, and sprinting demands (Riboli et al., 2020). However, limited evidence exists on age-related differences in physical demands among late-stage academy players. Therefore, this study investigated age-related differences in physical performance between U18 and U21 elite academy players across SSG formats defined by RPA.

Methods: Thirty-seven male elite academy players (U18: n=17; U21: n=20) from one club performed SSGs over 9 weeks. Formats were classified by RPA as small (>125 m²*player^-1), medium (125-225 m²*player^-1), and large (>225 m²*player^-1). Physical performance was measured via 10 Hz GPS with embedded inertial sensors. Outcome measures (per minute) were total distance (TD), high-speed running distance (HSRD; >20 km*h^-2), sprinting distance (SD; >25km*h^-1), accelerations (>2 m*s^-2), and decelerations (>2m*s^-2). Two-level mixed-effects models (measurements nested within players) tested effects of age category and SSG format (p<0.05).

Results: Multilevel analysis showed significant effects of both age category and SSG format on all physical variables (p<0.05). U21 players covered greater high-speed running (HSRD: 2.2 m*min^-1, p=0.003) and sprinting distances (SD: 1.0 m*min^-1, p=0.005) compared to U18 players. Whereas U18 players performed more accelerations (0.44*min^-1, p=0.014) and decelerations (0.44*min^-1, p=0.017). No significant difference was observed in total distance (TD: p=0.326). Across formats, large-sided games elicited the highest TD (129 m*min^-1), HSRD (10.0 m*min^-1), and SD (2.3 m*min^-1), followed by medium (122, 6,0, and 1.0 m*min^-1) and small formats (105, 1.9 and 0.1 m*min^-1). In contrast, small-sided games induced the most accelerations (3.6*min^-1) and decelerations (3.4*min^-1). All pairwise comparisons between formats were significant (p<0.05).

Discussion: The findings highlight age-related disparities in the physical demands of SSGs among late-stage academy players. Older players (U21) covered more distances at higher speeds, reflecting greater physical performance in larger available spaces. In contrast, younger players (U18) executed higher accelerations and decelerations, indicating a more intermittent movement profile. These findings align with previous work showing that older players show a greater physical performance, possibly influenced by differences in biological maturation and tactical behaviour (Buchheit et al., 2010; Radnor et al., 2021; Olthof et al., 2015). Furthermore, the progressive increase in external load across SSG formats confirms that RPA is a key determinant of physical demands, supporting the use of larger RPAs to replicate match demands (Riboli et al., 2022).

Conclusion: This study gives a better understanding of physical performance differences in elite late-stage academy soccer, highlighting the influence of age category and game format. Manipulating RPA provides a practical strategy for coaches to optimise training design and support the physical transition from late-stage academy levels.

References

Buchheit, M., Méndez-Villanueva, A., Simpson, B.M., & Bourdon, P.C. (2010). Match running performance and fitness in young soccer players. International journal of      sports medicine, 31(11), 818-825. https://doi.org/10.1055/s-0030-1262838

Bujalance-Moreno, P., Latorre-Roman, P.A., & Garcia-Pinillos, F. (2019). A systematic review on small-sided games in football players: Acute and chronic adaptations. Journal of Sports Sciences, 37(8), 921-949. https://doi.org/10.1080/02640414.2018.1535821

Hill-Haas, S.V., Coutts, A.J., Rowsell, G., et al. (2009). Generic versus small-sided game training in soccer. Int J Sports Med., 30(9), 636-42. https://doi.org/10.1055/s-0029-1220730

Morgans, R., Orme, P., Anderson, L., & Drust, B. (2014). Principles and practices of training for soccer. J Sport Health Sci., 3(4), 251-257. https://doi.org/10.1016/j.jshs.2014.07.002

Olthof, S.B.H., Frencken, W.G.P., & Lemmink, K. (2015). The older, the wider: On-field tactical behavior of elite-standard youth soccer players in small-sided games. Human Movement Science, 41, 92-102. https://doi.org/10.1016/j.humov.2015.02.004

Olthof, S.B.H., Frencken, W.G.P., & Lemmink, K. (2019). A Match-Derived Relative Pitch Area Facilitates the Tactical Representativeness of Small-Sided Games for the Official Match. J Strength Cond Res., 33(2), 523-530. https://doi.org/10.1519/JSC.0000000000002978

Radnor, J.M., Staines, J., Bevan, J., Cumming, S.P., Kelly, A.L., Lloyd, R.S., & Oliver, J.L. (2021). Maturity Has a Greater Association than Relative Age with Physical Performance in English Male Academy Soccer Players. Sports (Basel), 9(12), 171. https://doi.org/10.3390/sports9120171

Riboli, A., Coratella, G., Rampichini, S. et al. (2020). Area per player in small-sided games to replicate the external load and estimated physiological match demands in elite soccer players. PLoS One, 15(9), e0229194. https://doi.org/10.1371/journal.pone.0229194

Riboli, A., B.H. Olthof, S., Esposito, F., & Coratella, G. (2022). Training elite youth soccer players: area per player in small-sided games to replicate the match demands. Biology of Sport, 39(3), 579–598. https://doi.org/10.5114/biolsport.2022.106388