grouding down

I'm having a little pickle in that; when my player is moving downhill he becomes ungrounded every step. now Aesthetically this is no issue as it doesn't look like he's hopping down step by step, however I have a code to count time when your ungrounded(so falling and jumping) but I dont want it to count the time when your just walking downhill... I can't have it start counting OnButtonDown "jump" because that would mean falling from a cliff wouldnt count. can someone help me please?