Who are some of the fittest people in the U.S.? A recent report found that these six cities have the most physically active people. 6. Urban Honolulu, Hawaii 5. Santa Rosa, California 4. Greeley, Colorado 3. San Luis Obispo-Paso Robles, California 2. Fort Collins, Colorado 1. Boulder, Colorado Colorado takes the cake as the fittest state! As for the laziest city in America? Hickory–Lenoir–Morganton, North Carolina won the prize.