>>2775228japs are hardcore like that
>>>/jp/15990324And girls make sure to sit on their skirt, not their bare ass. Then there is the option of fleece or cotton panties.
Plus heat loss of the legs themselves is not that high compared to the groin region or the feet.
Ever looked at a jogger in winter? They don't do much to keep their lower arms and legs warm. Torso, head, shoulders, feet and hands are more important.
That said, I'm flouting my armchair expertise here.