Under normal circumstances, I would never advise anyone to eat pasta in Paris (unless it is part of beef bourguignon). But today is no ordinary day. At 8:45 a.m. 40,000 runners will depart from the Arc de Triomphe for the 26 miles and 385 yards (42.195 km) race. I’m going to need every last carb from that kilo of pasta I ate last night.