  We explore the behavior in time of the energy exchange between a system of
interest and its environment, together with its relationship to the
non-Markovianity of the system dynamics. In order to evaluate the energy
exchange we rely on the full counting statistics formalism, which we use to
evaluate the first moment of its probability distribution. We focus in
particular on the energy backflow from environment to system, to which we
associate a suitable condition and quantifier, which enables us to draw a
connection with a recently introduced notion of non-Markovianity based on
information backflow. This quantifier is then studied in detail in the case of
the spin-boson model, described within a second order time-convolutionless
approximation, observing that non-Markovianity allows for the observation of
energy backflow. This analysis allows us to identify the parameters region in
which energy backflow is higher.
