#2 Error when selecting XML workout

[ergo34]

When trying to load xml training programm the following error is thrown:

---- Debugging information ----
message : Cannot construct org.jergo.controller.PowerControllerItem as it does not have a no-args constructor
line number : 3
path : /Controller/items/WattControllerItem
cause-message : Cannot construct org.jergo.controller.PowerControllerItem as it does not have a no-args constructor
class : org.jergo.controller.Controller
cause-exception : com.thoughtworks.xstream.converters.reflection.ObjectAccessException
required-type : org.jergo.controller.PowerControllerItem
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