SDN Members don't see this ad. (About Ads) THought I'd be done with this forum forever, but a friend of mine studying for the mcat asked me a bio question and I couldn't provide the answer, and the more I think about it the more its driving me crazy. Arteriosclerosis is the arteries becoming less flexible. This leads to a rise in systolic pressure and a lowering of diastolic pressure. Why? Conceptually I'm not getting this. Wouldn't an inflexible artery lead to a lesser contraction, therefore lower BP?