Marg also won thirteen medals at the ICF Canoe Sprint World Championships with six golds (K-4 500 m: 1978, 1979, 1983; K-4 1000 m: 1978, 1979, 1981), five silvers (K-2 500 m:
1975, K-4 500 m: 1982, K-4 1000 m: 1975, 1982, 1983), and two bronzes (K-4 500 m: 1981, K-4 1000 m: 1973).