diff --git a/rowers/dataprep.py b/rowers/dataprep.py
index 35e8b645..7b8169b8 100644
--- a/rowers/dataprep.py
+++ b/rowers/dataprep.py
@@ -733,24 +733,24 @@ def save_workout_database(f2, r, dosmooth=True, workouttype='rower',
     ishard = False
     if workouttype == 'water':
         df = getsmallrowdata_db(['power', 'workoutid', 'time'], ids=[w.id])
-        # delta,cpvalues,avgpower = datautils.getsinglecp(row.df)
-        thesecs = totaltime
-        maxt = 1.05 * thesecs
-        if maxt > 0:
-            logarr = datautils.getlogarr(maxt)
-            dfgrouped = df.groupby(['workoutid'])
-            delta, cpvalues, avgpower = datautils.getcp(dfgrouped, logarr)
+        if df['power'].mean():
+            thesecs = totaltime
+            maxt = 1.05 * thesecs
+            if maxt > 0:
+                logarr = datautils.getlogarr(maxt)
+                dfgrouped = df.groupby(['workoutid'])
+                delta, cpvalues, avgpower = datautils.getcp(dfgrouped, logarr)
 
-            res, btvalues, res2 = utils.isbreakthrough(
-                delta, cpvalues, r.p0, r.p1, r.p2, r.p3, r.cpratio)
-        else:
-            res = 0
-            res2 = 0
-        if res:
-            isbreakthrough = True
-            res = datautils.updatecp(delta, cpvalues, r)
-        if res2 and not isbreakthrough:
-            ishard = True
+                res, btvalues, res2 = utils.isbreakthrough(
+                    delta, cpvalues, r.p0, r.p1, r.p2, r.p3, r.cpratio)
+            else:
+                res = 0
+                res2 = 0
+            if res:
+                isbreakthrough = True
+                res = datautils.updatecp(delta, cpvalues, r)
+            if res2 and not isbreakthrough:
+                ishard = True
 
     # submit email task to send email about breakthrough workout
     if isbreakthrough: