The fabric I was planning to use, and used, is a wicking, highly elastic 180g/sqm bike-jersey with a maximum stretch of 40% lengthwise and 70% crosswise.
As the pattern comes with two different patterns, I asked Birgit which of the patterns I should use; the pattern for a more stretchy crosswise fabric, 40-50% crosswise & 15% lengthwise, or the pattern for a less crosswise fabric, 20% crosswise & 15% lengthwise.
Birgit suggested to me to use the pattern for the single jersey (less stretchy) pattern. I followed her suggestion. I guess you can always make it tighter but not looser.
Anyways, it is perfect for all my high activity sports.
Hiking Pants with Design seams