  In this article we identify the key elements that govern the propagation of
muons from the production in extensive air showers to ground. We describe a
model based on simple assumptions that propagates the muons starting from the
few relevant distributions at production. We compare the results to the ground
distributions given by a full air shower Monte Carlo. This study is motivated
by the need of modeling the muon component in extensive air showers with the
goal of experimentally reconstructing their distributions at production, which
act as a footprint of the hadronic cascade.
