She was a pioneer in the early period of international women's walking and broke several European records.

Her 10 kilometres race walk time of 47:58.2 minutes in 1981 was the first ever ratified by the European Athletics Association and she improved this to 47:49.3 the following year, and twice more to 46:14.3 in 1985 and 46:13.2 in 1986.

[2] In international competition, her greatest achievement was a silver medal in the 10 km walk at the 1986 European Athletics Championships, finishing behind Spain's Mari Cruz Díaz in the first ever women's European Championships event in walking.

[3] The following year she took part in the first World Championships event and was eleventh in the women's 10 km walk.

[7] Jansson was twice winner at the prestigious annual Coppa Città di Sesto San Giovanni meet.