Effects of Chronological Age, Relative Age, and Maturation Status on Accumulated Training Load and Perceived Exertion in Young Sub-Elite Football Players
The aims of this study were 1) to analyze the influence of chronological age, relative age, and
biological maturation on accumulated training load and perceived exertion in young sub-elite
football players and 2) to understand the interaction effects amongst age grouping,maturation
status, and birth quartiles on accumulated training load and perceived exertion in this target
population. A 6-week period (18 training sessions and 324 observation cases) concerning 60
young male sub-elite football players grouped into relative age (Q1 to Q4), age group (U15,
U17, and U19), and maturation status (Pre-peak height velocity (PHV), Mid-PHV, and Post-
PHV) was established. External training load data were collected using 18 Hz global positioning
system technology (GPS), heart-rate measures by a 1 Hz short-range telemetry system, and
perceived exertion with total quality recovery (TQR) and rating of perceived exertion (RPE). U17
players and U15 players were 2.35 (95% CI: 1.25–4.51) and 1.60 (95% CI: 0.19–4.33) times
more likely to pertain to Q1 and Q3, respectively. A negative magnitude for odds ratio was
found in all four quartile comparisons within maturation status (95% CI: 6.72–0.64), except for
Mid-PHV on Q2 (95% CI: 0.19–4.33). Between- and within-subject analysis reported
significant differences in all variables on age group comparison measures (F = 0.439 to
26.636, p = 0.000 to 0.019, η2 = 0.003–0.037), except for dynamic stress load (DSL).
Between-subject analysis onmaturity status comparison demonstrated significant differences
for all training load measures (F = 6.593 to 14.424, p = 0.000 to 0.037, η2 = 0.020–0.092).
Interaction effects were found for age group xmaturity band x relative age (Λ Pillai’s = 0.391, Λ
Wilk’s = 0.609, F = 11.385, p = 0.000, η2 = 0.391) and maturity band x relative age (Λ Pillai’s =
0.252, Λ Wilk’s = 0.769,F=0.955, p = 0.004, η2 = 0.112). Current research has confirmed the
effects of chronological age, relative age, and biological maturation on accumulated training
load. Perceived exertion does not seem to show any differences concerning age group or
maturity status. Evidence should be helpful for professionals to optimize the training process
and young football players’ performance.
This work is supported by national funds (FCT—Portuguese Foundation for Science and Technology) under the project UIBD/DTP/04045/2020
