Hmmm...never thought about it... when it gets cold, I wear layers...wear leggings under the pants so the pants are still usable year round. Like the stuff under armour sells....

Thanks for the response, Annie. These I wear exclusively during the cold season (they're not for gym use, e.g.), which in MN runs from October through early May. I'd just like to have them warmer in general, like a favorite pair that I wore into the ground.

Gary

For pratical purposes I suppose it has to be some kind of light cotton jersey or synthetic jersey. That will add a warming layer with out too much bulk, and easy to throw in the washer. Its' easy to get carried away with merino jersey or silk, which might add extra comfort and warmth, but will make cleaning not so easy. The jogging pants in themselves are most likely something that needs a more heavy duty washing powder to turn out clean.

There might be an option in viscose, both jersey and woven fabrics, but might take more search to find the correct fabric. I'm afraid I don't have a very specific recommendation.