diff --git a/checkstyle.xml b/checkstyle.xml
index 9c23689..8399307 100644
--- a/checkstyle.xml
+++ b/checkstyle.xml
@@ -190,7 +190,7 @@
              value="Member name ''{0}'' must match pattern ''{1}''."/>
     </module>
     <module name="ParameterName">
-      <property name="format" value="^[_]*[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
+      <property name="format" value="^[_]*[a-z][a-zA-Z0-9]*$"/>
       <message key="name.invalidPattern"
              value="Parameter name ''{0}'' must match pattern ''{1}''."/>
     </module>
@@ -205,7 +205,7 @@
              value="Catch parameter name ''{0}'' must match pattern ''{1}''."/>
     </module>
     <module name="LocalVariableName">
-      <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
+      <property name="format" value="^[_]*[a-z][a-zA-Z0-9]*$"/>
       <message key="name.invalidPattern"
              value="Local variable name ''{0}'' must match pattern ''{1}''."/>
     </module>