GETTY IMAGES Better sleep. That's all that could be standing between you and a new PB. Too good to be true? Not according to Mara Yamauchi, who set a new marathon PB (2:25:03) at the International Women's Marathon in Tokyo in November. "Sleep is one
can take days off." And don't try to beat your run-to-work PB. "This will add pressure." Mix it up Running a different route everyday will keep you motivated. Go to sustrans.org.uk to find 12,000 miles of traffic-free routes near you. Come up
and maintain a reasonable pace, you still only have about 2,000 calories worth of glycogen stored in your muscles – enough to get most runners to about mile 18 or 20," he says. "As glycogen reserves are used up and fatty acid metabolism increases, your heart
