In soccer, the assessment of the load imposed by training and a match is recognized as a fundamental task at any competitive level. The objective of this study is to carry out a systematic review on internal and external load monitoring during training and/or a match, identifying the measures used. In addition, we wish to make recommendations that make it possible to standardize the classification and use of the different measures. The systematic review was carried out according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The search was conducted through the electronic database Web of Science, using the keywords “soccer” and “football”, each one with the terms “internal load”, “external load”, and “workload”. Of the 1223 studies initially identified, 82 were thoroughly analyzed and are part of this systematic review. Of these, 25 articles only report internal load data, 20 report only external load data, and 37 studies report both internal and external load measures. There is a huge number of load measures, which requires that soccer coaches select and focus their attention on the most useful and specific measures. Standardizing the classification of the different measures is vital in the organization of this task, as well as when it is intended to compare the results obtained in different investigations.

The present study evaluated how the combination of ego-and task-involving climate perceptions related to youth soccer athletes' perceptions of team cohesion. We hypothesized that athletes would perceive their group to be less cohesive as ego climate perceptions increased in salience relative to task climate perceptions. In addition, the factor structure and longitudinal measurement invariance of Youth Sport Environment Questionnaire (YSEQ)-Portuguese version was also analyzed. A total of 956 national level youth male soccer athletes' belonging to 49 different teams participated in the study. Using a prospective design with two time points, the polynomial regression with a response surface analysis indicated that the effect of an ego-involving climate on task cohesion varied as a function of task-involving climate perceptions. Specifically, athletes reported lower levels of task cohesion as ego-involving climate perceptions began to predominate over task-involving climate perceptions. Furthermore, a strong taskinvolving climate buffered against the negative effects of ego-involving climate perceptions on task cohesion. Regarding social cohesion, we only observed a positive linear association between task-involving climate perceptions and social cohesion. Our findings support the validity and reliability of two factors underlying the YSEQ and its longitudinal invariance across time in an elite youth sample. Future studies should strive to replicate these results in other sports and with female athletes. Our results provide insight into how task-involving and ego-involving climate perceptions combine to shape how elite youth athletes view their group environment.

Assessment of the physical dimension implicit in the soccer match is crucial for the improvement and individualization of training load management. This study aims to: (a) describe the external match load at the amateur level, (b) analyze the differences between playing positions, (c) verify whether the home/away matches and if (d) the phase (first or second) of the championship influence the external load. Twenty amateur soccer players (21.5 ± 1.9 years) were monitored using the global positioning system. The external load was assessed in 23 matches, where 13 were part of the first phase of the competition (seven home and six away matches) and the other 10 matches belonged to the second (and final) phase of the championship (five home and five away matches). A total of 173 individual match observations were analyzed. The results showed significant differences between playing positions for all the external load measures (p < 0.001). There were higher values observed in the total distance covered for central defenders (p = 0.037; ES = 0.70) and in high-intensity decelerations for forwards (p = 0.022; ES = 1.77) in home matches than in away matches. There were higher values observed in the total distance (p = 0.026; ES = 0.76), relative distance (p = 0.016; ES = 0.85), and moderate-intensity accelerations (p = 0.008; ES = 0.93) for central defenders, in very high-speed running distance for forwards (p = 0.011; ES = 1.97), and in high-intensity accelerations (p = 0.036; ES = 0.89) and moderate-intensity decelerations (p = 0.006; ES = 1.11) for wide midfielders in the first phase than in the second phase of the championship. Match location and championship phase do not appear to be major contributing factors to influence the external load while the playing position should be used as the major reference for planning the external training load.