Kettlebells - interfere with weight training "recovery?"

nyspotlight

Hi!

I'm doing Chalean extreme - with heavy weights. I do m, w, f lifting. Cardio on t, th, sat.

I miss my kettlebells. But are they more a strength or cardio exercise? Or a definite hybrid.

If I do kettlebells on my "cardio" days, would it interfere with muscle recovery, or do they not really build muscle?

Thanks!