A kangaroo jumped onto a woman cycling in South Australia, rupturing her breast implants and using her as a "little airbag", she told local media this morning.

Sharon Heinrich, 45, was on the Riesling Trail in the Clare Valley with her friend when the "cute" kangaroo she nicknamed "Skip" jumped from an embankment and landed on her, she told local newspaper the Northern Argus.

"I saw him and thought 'oh isn't he cute' - then he was on top of me.

"I'm 5'4" [1.63m] and he was taller than me, and so heavy. Once he landed on me, he used me to launch off again, which caused more damage."

Ms Heinrich said the kangaroo then bounded on her friend.

"He ... took our cycles out and used myself as a little airbag and then [has] taken Helen out and hopped away into the wilderness," she told the Australian Broadcasting Corporation.

Ms Heinrich said she suffered ruptured breast implants, three cracked ribs, grazes and a numb leg, while friend Helen Salter had concussion and whiplash.

"[The implants] are silicon and saline, and the saline will just go through your body, but the silicon now congeals so it stays within the area but it's very painful, it's up there with cracked ribs," she told the national broadcaster.

Ms Heinrich said she would undergo surgery in the city of Adelaide on Thursday but urged other cyclists to keep using the trail despite the encounter.

"Please don't let anybody be scared of that Riesling Trail, because it was a beautiful, beautiful ride before 'Skip' played," she said.