diff --git a/liquidprompt b/liquidprompt
index 58b7285..2253d38 100755
--- a/liquidprompt
+++ b/liquidprompt
@@ -1351,18 +1351,20 @@ fi
 
 _lp_reset_runtime()
 {
-    if $_LP_SHELL_bash; then
-        # Compute number of seconds since program was started
-        _LP_RUNTIME_SECONDS=$((SECONDS - _LP_RUNTIME_LAST_SECONDS))
-
-        # If no proper command was executed (i.e., someone pressed enter without entering a command),
-        # reset the runtime counter
-        [ "$_LP_RUNTIME_COMMAND_EXECUTED" != 1 ] && _LP_RUNTIME_LAST_SECONDS=$SECONDS && _LP_RUNTIME_SECONDS=0
-
-        # A proper command has been executed if the last command was not related to Liquid Prompt
-        [ "$BASH_COMMAND" = _lp_set_prompt ]
-        _LP_RUNTIME_COMMAND_EXECUTED=$?
+    if $_LP_SHELL_zsh; then
+        return
     fi
+
+    # Compute number of seconds since program was started
+    _LP_RUNTIME_SECONDS=$((SECONDS - _LP_RUNTIME_LAST_SECONDS))
+
+    # If no proper command was executed (i.e., someone pressed enter without entering a command),
+    # reset the runtime counter
+    [ "$_LP_RUNTIME_COMMAND_EXECUTED" != 1 ] && _LP_RUNTIME_LAST_SECONDS=$SECONDS && _LP_RUNTIME_SECONDS=0
+
+    # A proper command has been executed if the last command was not related to Liquid Prompt
+    [ "$BASH_COMMAND" = _lp_set_prompt ]
+    _LP_RUNTIME_COMMAND_EXECUTED=$?
 }
 
 if [ "$LP_ENABLE_RUNTIME" = 1 ]