extreme leg-stretching exercise; crotch flexibility exercise
A sumo training exercise where the wrestler sits in a wide straddle and leans forward to stretch the inner thighs and groin. Used to improve flexibility and prevent injury.
Sumo wrestlers loosen up their bodies with the matawari exercise every morning.
Compound of 股 (mata, 'crotch, groin') and 割り (wari, 'split, divide'), literally 'crotch splitting'.