diff --git a/backend/routers/goals.py b/backend/routers/goals.py
index ed4df73..d2edb4e 100644
--- a/backend/routers/goals.py
+++ b/backend/routers/goals.py
@@ -438,6 +438,14 @@ def update_goal(goal_id: str, data: GoalUpdate, session: dict = Depends(require_
     """Update existing goal"""
     pid = session['profile_id']
 
+    # Debug logging
+    print(f"[DEBUG] update_goal called with:")
+    print(f"  goal_id: {goal_id}")
+    print(f"  start_date: {data.start_date} (type: {type(data.start_date)})")
+    print(f"  start_value: {data.start_value}")
+    print(f"  target_date: {data.target_date}")
+    print(f"  target_value: {data.target_value}")
+
     with get_db() as conn:
         cur = get_cursor(conn)