Development and evaluation of the “Anstrengungsskala Sport” (Effort Scale Sport)

Due to its simplicity and user-friendliness, the Category Ratio Scale (CR10 scale) or a single-item scale is preferred for recording subjective perception of internal load in training and competition. The CR10 scale represents a non-linear, slightly positively accelerated function related to internal load, which is translated as “Anstrengungsempfinden” (effort) in the authorized German version. However, it should be noted that the existing scales do not include complete level descriptions and/or the level description allow overlap with related constructs, e.g., fatigue. In contrast, the “Anstrengungsskala Sport“ (Effort Scale Sport) is characterized by complete level descriptions and conceptual clarity with the comparative declension of the adjective strenuous. Based on a rational construction strategy as well as a systematic item analysis, it can be shown that the prerequisites for the use of the ASS as a ratio scale are given, which allows reliable and conceptually unambiguous measurement of effort.