setupExternalLoads.xml

<?xml version="1.0" encoding="utf-8"?>
<OpenSimDocument Version="30000">
   <ExternalLoads name="generic">
      <objects>
         <ExternalForce name="forceRight">
            <isDisabled>false</isDisabled>
            <applied_to_body>calcn_r</applied_to_body>
            <force_expressed_in_body>ground</force_expressed_in_body>
            <point_expressed_in_body>ground</point_expressed_in_body>
            <force_identifier>forceRight</force_identifier>
            <point_identifier>pointRight</point_identifier>
         </ExternalForce>
         <ExternalForce name="forceLeft">
            <isDisabled>false</isDisabled>
            <applied_to_body>calcn_l</applied_to_body>
            <force_expressed_in_body>ground</force_expressed_in_body>
            <point_expressed_in_body>ground</point_expressed_in_body>
            <force_identifier>forceLeft</force_identifier>
            <point_identifier>pointLeft</point_identifier>
         </ExternalForce>
      </objects>
      <lowpass_cutoff_frequency_for_load_kinematics>-1</lowpass_cutoff_frequency_for_load_kinematics>
   </ExternalLoads>
</OpenSimDocument>