Mountain Climb push back physics mechanics

Hello people,

So I am trying to simulate a mountain climb sequence in Unity. I am using the character controller to move the player in the upward direction. I am able to move the player up and down, sideway with a little bob effect using the sin and cosine funtions. But what I am really trying to do here is implement a push up physics thing when the player moves up with the latches. Something similar to the MW2 ice climbing sequence.

http://www.youtube.com/watch?v=5aMQ9eG8hOI

I obviously dont want the exact same physics as shown in MW2 but something close. Does anyone have any idea how we can achieve that? I have all the upward and lateral moments on the mountain going smooth but I want a realistic physics mechanism in place!

Please share your opinions

 

Anyone can please help?

Thanks!