public function requestAuthToken($username, $password) {
        $response = parent::requestAuthToken($username, $password);
        $data = $this->decodeResponse($response);

        if (count($data) === 0) {
            throw new EndomondoApiOldException('Wrong username or password.');
        }

        $this->setAccessToken($data['authToken']);
        $this->setUserId($data['userId']);

        return $data;
    }