diff --git a/src/ErgFile.cpp b/src/ErgFile.cpp
index c3ad61d3b..9ff18c616 100644
--- a/src/ErgFile.cpp
+++ b/src/ErgFile.cpp
@@ -19,11 +19,10 @@
 #include "ErgFile.h"
 
 
-ErgFile::ErgFile(QString filename, int &mode)
+ErgFile::ErgFile(QString filename, int &mode, double Cp)
 {
     QFile ergFile(filename);
     int section = NOMANSLAND;            // section 0=init, 1=header data, 2=course data
-    double Cp=285;                       // default to 285 if zones are not set
     leftPoint=rightPoint=0;
     MaxWatts = Ftp = 0;
     int lapcounter = 0;
@@ -33,11 +32,6 @@ ErgFile::ErgFile(QString filename, int &mode)
     long rdist = 0; // running total for distance
     long ralt = 200; // always start at 200 meters just to prettify the graph
 
-    // Get users CP for relative watts calculations
-    QDate today = QDate::currentDate();
-    int range = mainwindow->zones()->whichRange(today);
-    if (range != -1) Cp = mainwindow->zones()->getCP(range);
-
     // open the file
     if (ergFile.open(QIODevice::ReadOnly | QIODevice::Text) == false) {
         valid = false;
diff --git a/src/ErgFile.h b/src/ErgFile.h
index d8a162a7c..be3ade371 100644
--- a/src/ErgFile.h
+++ b/src/ErgFile.h
@@ -29,7 +29,6 @@
 #include <QTextStream>
 #include <QRegExp>
 #include "Zones.h"      // For zones ... see below vvvv
-#include "MainWindow.h" // gets access to mainwindow to read zones info
 
 // which section of the file are we in?
 #define NOMANSLAND  0
@@ -61,7 +60,7 @@ class ErgFileLap
 class ErgFile
 {
     public:
-        ErgFile(QString, int&);       // constructor uses filename
+        ErgFile(QString, int&, double Cp);       // constructor uses filename
         ~ErgFile();             // delete the contents
 
         bool isValid();         // is the file valid or not?
diff --git a/src/RealtimeWindow.cpp b/src/RealtimeWindow.cpp
index fbbb9f46d..a71642a8a 100644
--- a/src/RealtimeWindow.cpp
+++ b/src/RealtimeWindow.cpp
@@ -716,7 +716,13 @@ RealtimeWindow::SelectWorkout(int index)
             tr("Open Workout File"), home.dirName(), tr("Workout Files (*.erg *.mrc *.crs)"));
 
         if (!filename.isEmpty()) {
-            ergFile = new ErgFile(filename, mode);
+            // Get users CP for relative watts calculations
+            QDate today = QDate::currentDate();
+            double Cp=285;                       // default to 285 if zones are not set
+            int range = main->zones()->whichRange(today);
+            if (range != -1) Cp = main->zones()->getCP(range);
+
+            ergFile = new ErgFile(filename, mode, Cp);
             if (ergFile->isValid()) {
 
                 // success! we have a load file