On one trip, we stayed nearly a month in a small town named Fiuggi south of Rome, and I never saw a runner until one day I visited an untravelled side road and spotted half a dozen. Italians know the best areas to run, but you'll find them only by luck, or by knowing an Italian runner. Best advice is to relax, content that all the walking done from church to museum will keep you in shape until you can find the occasional convenient running area like Rome's Villa Borghesi. Surround that with antipasto, salad and fruit, and a meal can last several hours. Usually, I skip around the menu, ordering a first plate at one meal, a second plate the next.
Italian wines are light.
Continental breakfasts consist of little more than coffee and rolls, although major hotels sometimes offer more impressive spreads. One of the great pleasures of visiting Italy is sitting at a sidewalk cafe, sipping a drink and watching everybody prance by. Nobody can prance like an Italian. They call it displaying la bella figura. It's the siren's song that keeps luring me back to Italy.