The Ergodicity Problem in Sports: Group Results of Load and Recovery Are Not Applicable to Individual Athletes

    Activity: Talk and presentationAcademic presentationAcademic


    Gimme 5 oral presentation:
    The process of load and recovery is a key concept to optimize sports performance and well-being. To date, studies are typically conducted at the group level, which can pose limits on applying research findings to individual athletes (Davids et al., 2003; Glazier & Mehdizadeh, 2019; Hill et al., 2020). Indeed, group-level statistics in psychology are often not generalizable to processes at the individual level, which is called the “ergodicity problem” (Fisher et al., 2018; Molenaar & Campbell, 2009). The aim of the present research was to investigate this ergodicity problem in the study of load and recovery in football. We collected internal training load (RPE*training duration) and recovery (TQR) data on a daily basis across two seasons among 82 youth male players of a professional football club. Next, we calculated the univariate distributions and bivariate correlations on both the group and the individual level. Group- and individual-level analysis resulted in different statistical outcomes, particularly with regard to load. Standard deviations of individuals were up to 7.63 times larger than standard deviations of the group. In addition, at either level, we observed different correlations between the two variables. The results suggest that the process of load and recovery in athletes is nonergodic. Recommendations for training programs of individual athletes may be suboptimal, or even erroneous, when guided by group-level outcomes. Researchers should therefore consider shifting their focus to the analysis of processes on the individual level.
    Event titleFEPSAC 2022: Sport, exercise and performance psychology: challenges and opportunities in a changing world
    Event typeConference
    LocationPadua, ItalyShow on map
    Degree of RecognitionInternational


    • FEPSAC2022
    • Sportpsychology
    • Ergodicity
    • Personalized approach
    • Load and recovery
    • Gimme 5
    • Conference
    • Time series
    • Sports
    • Football