  The electromagnetic and the muonic longitudinal profile at production
enclosure important information about the primary particle and the hadronic
interactions that rule the shower development. In fact, these two profiles
provide two different insights of the shower: the electromagnetic component
gives a measurement of the energy and the strength of the neutral pion channel;
while the muonic profile, being intimately related with the charged mesons
decays, can be used as a direct probe for the high energy hadronic
interactions.
  In this work we explore the interplay between the electromagnetic and muonic
profiles, by analysing their phenomenologic behaviour for different primary
masses and energies, zenith angles, and also different high energy hadronic
interaction models. We have found that the muonic longitudinal profile at
production displays universal features similar to what is known for the
electromagnetic one. Moreover, we show that both profiles have new primary mass
composition variables which are fairly independent of the high energy hadronic
interaction model.
  Finally we discuss how the information in the electromagnetic and the muonic
longitudinal profile can be combined to break the degeneracy between the
primary mass composition and the high energy hadronic physics.
