Fig. 2.

Correlogram reporting the relationship between the variables. Positive relationship is in color blue and negative relationship in red color. Absence of relation is in white. Non-significant correlations are crossed (p > .05). In the upper part, an ellipse represents the orientation and the strength of the relation, the narrower the ellipse is, the higher the strength is. In the lower part, the rounded Spearman rho is indicated. Order of the variables is determined by hierarchical clustering with the “complete” agglomeration method. “sc.” is an abbreviation for scaled (centered and scaled). ULC ultrasound lung comet, SCUBA self-contained underwater breathing apparatus, Gas gas during decompression stop, O ₂ oxygen, VAS visual analog scale, RPE rating of perceived exertion, Temp. temperature