Abstract
This study aims to investigate the relationship between subjective and external measures
of load in professional youth football players whilst accounting for the effect of
training theme or competition. Data from ratings of perceived exertion and global
positioning system-derived measures of external training load were collected from
20 professional youth players (age=17.4±1.3 yrs) across a 46-week season. General
characteristics of training sessions were categorised based on their proximity to
match day. The underlying structure of the data was investigated with principal component
analysis. An extraction criterion comprising eigenvalues >1 was used to identify which
components to retain. Three components were retained for training performed three
days prior to match day (80.2% of variance), with two components (72.9–89.7% of variance)
retained for all other modes. Generally, the first component was represented by measures
of volume (Total Distance, PlayerLoad and low intensity running) whilst the second
and third components were characterised by measures of intensity. Identification of
multiple components indicates that load monitoring should comprise multiple variables.
Additionally, differences in the underlying structure across training days that reflected
different goals suggest that effective monitoring should be specific to the demands
of different session types.
Key words
training load - monitoring - session-rpe - team sports - football - workload
