Table 6. Key outcomes of included studies.
Author (Year) Compared groups Key Outcomes for BB Intervention Tactical performance
Physiological performance Psychological performance Technical performance
Abbott et al. (2019) Chronological age None Early developers:
↑ RPE		 Early developers:
↑ Short pass, ↓ Dribbles
On-time developers:
↑ Short pass, ↑ Dribbles
↓ Long pass,
Late developers:
↑ Tackles, ↓ Long pass		 None
Arede et al. (2024) Chronological age ↓ Distance covered
↓ Decelerations
↓ Average speed
↓ Body impacts
↓ Peak heart rate		 None None None
Lüdin et al. (2022) Chronological age U13 MO Low:
↓ High Accelerations
U13 MO High:
↑ High accelerations
U14 MO Low:
↓ High accelerations		 None U13 MO Low:
↑ Conquered balls
U13 MO High:
↓ Conquered balls
U14 MO Low:
↑ Conquered balls,
↑ Attacked balls		 None
Romann et al. (2020) Chronological age ↓ Jogging distance,
↓ Running distance
↓ High speed running		 None ↑ Duels
↑ Unsuccessful passes		 ↑ Set Pieces
↓ Mean
possession time
Towlson et al. (2021a) Mixed-maturity None None No consistent differences Early developers:
↓ Degree centrality
Towlson et al. (2021b) Mixed-maturity No consistent differences Pre-PHV vs Post-PHV:
↑ Positive attitude, ↑ Confidence
↑ Competitiveness
↑ Total psychological score
↑ sRPE-TL		 None None
Towlson et al. (2022) Mixed-maturity None None No consistent differences No consistent
differences
Salter et al. (2023) Chronological age Attenuated pre-post changes:
↓ Absolute stiffness
↓ Stride length, ↓ Cadence		 Post-PHV:
↓ RPE-T		 None None
Salter et al. (2025) Chronological age Post-PHV:
↑ High-intensity distance		 None ↓ One-touch actions
Post-PHV:
↓ Total touches,
↓ Total possessions		 ↑ Time per
possession
Robinson et al. (2025) Chronological age None ↑ Competitiveness, ↑ Confidence
↑ Decision making
↑ Composure, ↑ X-factor		 None None
de Macedo et al. (2025) Chronological age Pre-PHV:
↑ ETL
PHV:
↓ ETL		 ↔ ITL None None
Barrett et al. (2022) Mixed-maturity None ↓dRPE None None
Abbreviations: PHV, peak height velocity; RPE-T, technical/cognitive exertion; ETL, external load; ITL, internal load.