diff --git a/src/fit2gpx.py b/src/fit2gpx.py
index cf931db..281aa60 100644
--- a/src/fit2gpx.py
+++ b/src/fit2gpx.py
@@ -8,6 +8,7 @@
 import pandas as pd
 import gpxpy.gpx
 import fitdecode
+from math import isnan
 
 
 # MAIN CONVERTER CLASS
@@ -176,12 +177,20 @@ def dataframe_to_gpx(self, df_points, col_lat='latitude', col_long='longitude',
         # Step 3: Add points from dataframe to GPX track:
         for idx in df_points.index:
             # Create trackpoint:
-            track_point = gpxpy.gpx.GPXTrackPoint(
-                latitude=df_points.loc[idx, col_lat],
-                longitude=df_points.loc[idx, col_long],
-                time=pd.Timestamp(df_points.loc[idx, col_time]) if col_time else None,
-                elevation=df_points.loc[idx, col_alt] if col_alt else None
-            )
+            if isnan(df_points.loc[idx, col_alt]):
+                track_point = gpxpy.gpx.GPXTrackPoint(
+                    latitude=df_points.loc[idx, col_lat],
+                    longitude=df_points.loc[idx, col_long],
+                    time=pd.Timestamp(df_points.loc[idx, col_time]) if col_time else None,
+                    # Do not include elevation if nan
+                )
+            else:
+                track_point = gpxpy.gpx.GPXTrackPoint(
+                    latitude=df_points.loc[idx, col_lat],
+                    longitude=df_points.loc[idx, col_long],
+                    time=pd.Timestamp(df_points.loc[idx, col_time]) if col_time else None,
+                    elevation=df_points.loc[idx, col_alt] if col_alt else None,
+                )
 
             # Append GPX_TrackPoint to segment:
             gpx_segment.points.append(track_point)