"Mud, mud, glorious mud," I hum beneath my breath as my left leg disappears to the knee in the thick primordial ooze of the Kashima Mudflats in Saga Prefecture.
Part of the tidal zone of the Ariake Sea, at low tide the mudflats stretch unbroken from the town's concrete flood defenses 300 meters or more to the water beyond. The muted gray expanse varies only in the presence of the not-yet-evaporated pools of sea water that reflect the sky above.
On this sunny afternoon, 40 of us are trudging through the mud to the start line of Kashima's annual "Gatalympic" event, an assault course that stretches across the flats. The rules are simple: the first to reach the flag at the end wins.