Adding this to the functions.php of your wordpress theme will change the default mysite.com/author/name to mysite.com/profile/name, however you can change this to user or anything that you would like.

change_author_base.php

<?php

add_action('init', 'change_author_base');
function change_author_base() {
    global $wp_rewrite;
    $author_slug = 'profile'; // change slug name
    $wp_rewrite->author_base = $author_slug;
}

?>