How to decline snow tubing for a first date...?

So I'm going out with this boy on Saturday. I left the planning up to him, obviously. He says he wants to do something fun for our first date rather than just talk which is fine by me. But he suggested snow tubing and I don't want to because...

1. I'll have to wear a million layers, not sexy.

2. It'll be frigid and flurrying Saturday, enough said.

3. I'm not a big fan of playing in the snow.

4. I hate doing anything active besides working out because I'm horribly uncoordinated and would inevitably make an ass out of myself.

So how do I tell him I'd rather not go snow tubing without looking like a high-maintenance, party pooping bitch?
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+1 y
UGH. GAG keeps putting questions in the wrong category. -_-
How to decline snow tubing for a first date...?
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