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During overground wheelchair propulsion, upper-body (UB) movement causes intracycle velocity variations that are neglected by current wheelchair simulators. This could affect the external validity of wheelchair propulsion on simulators. In this study, we investigated ways to incorporate these dynamics into the dynamic model (DM) reproduced by wheelchair simulators. We aimed to maximize the DM accuracy and minimize the number of required inputs. First, two DMs were presented: Model RL represented propulsion on a typical roller-based wheelchair simulator and model UB represented overground propulsion, modeling the UB as five rigid bodies. Then, three new DMs were presented: Model trunk (TR), model upper arm (UA), and model forearm (FA); these models simplified model UB by estimating the UB kinematics based on the acceleration of only one segment. For all DMs, wheelchair velocity prediction was tested overground at a self-selected velocity among 19 experienced manual wheelchair users with a spinal cord injury. UB kinematics was reconstructed based on personalized kinematic patterns recorded on a wheelchair simulator. Models UB and UA were the most accurate: they reduced the root-mean-square intracycle velocity prediction error from 0.044 m/s (RL) to 0.026 m/s (UB) and 0.024 m/s (UA), and reduced the velocity peak time prediction error from $-$27.7% (RL) to 1.7% (UB) and $-$7.3% (UA). Implementing model UA instead of model RL on a wheelchair simulator may improve the external validity of wheelchair propulsion on a simulator. [ABSTRACT FROM PUBLISHER]