public function patch($userId, $dataSourceId, Fitness_DataSource $postBody, $optParams = array())
  {
    $params = array('userId' => $userId, 'dataSourceId' => $dataSourceId, 'postBody' => $postBody);
    $params = array_merge($params, $optParams);
    return $this->call('patch', array($params), "Fitness_DataSource");
  }