You can use Administration theme or hook_admin_paths_alter() in your custom module.

/**
 * Implements hook_admin_paths_alter().
 */
function my_module_admin_paths_alter(&$paths) {
  $paths['user/*/edit'] = FALSE;
}

For Drupal 7 you can use Administration theme or hook_admin_paths_alter() in your custom module.

/**
 * Implements hook_admin_paths_alter().
 */
function my_module_admin_paths_alter(&$paths) {
  $paths['user/*/edit'] = FALSE;
}

For Drupal 8, see https://www.drupal.org/node/2224207.