Abstract
This study aimed to investigate training-induced fitness changes and their
relationship with training-competition load during half a soccer season (18
wks). Training load [heart rate (HR) and ratings of perceived exertion (RPE)]
and match time were monitored, including 108 training (3 223
individuals) and 23 match sessions, in 38 youth elite male soccer players.
Fitness variables were assessed before and after the study. Yo-Yo intermittent
recovery test 1 (Yo-Yo IRT1) improved (P<0.001; 90%CI:
418–632 m; ES: 2.14). Anthropometrical, jump, sprint, and
change-of-direction measures remained unchanged. Jump test correlated with
sprint (r=0.74; P<0.001;
SEE=3.38 m·s−1) and Yo-Yo IRT1
(r=−0.58; P=0.005; SEE=4.11 m) tests.
Initial sum of 6 skinfolds was associated with changes in this same measure
(r=−0.51; P<0.001; SEE=21%). Initial
Yo-Yo IRT1 results were related to changes in Yo-Yo IRT1
(r=−0.84; P<0.001; SEE=10%) and match
time played (r=0.44; P=0.033; SEE=445 m). Mean
RPE records were related to training spent within 75–90% maximal
HR (r=0.54; P<0.001; SEE=4%). The half-season
was beneficial for endurance running performance but not for lower-limb
strength-velocity production capacity. The more aerobically deconditioned
players played fewer minutes of match, although they showed the greatest
improvements in endurance performance. Non-soccer-specific, scientifically
based, and individualized fitness programs in addition to soccer-specific
training are recommended.
Key words
European football - internal load - soccer match - preseason - small-sided games - countermovement jump
