More new evidence exercise can ward off Alzheimer's was announced this week, as a result of a study of more than 1,700 people that generated statistically significant results to what seems, on the face of it, to be common sense. So, now is the time to get moving. On our hikes and walks we often see people who are taking this to heart by enjoying 5-7 mile walks. Where are the hiking trails? many of our urban areas have relatively pristine experiences nearby: the Santa Cruz Mtns has numerous walking trails almost from the start of the hills to the Ocean; the Santa Monica Mtns have a number of excellent trails as well in a slightly more arid environment. What's your favorite?