/**
  * Passes data from a Cardio object to the
  * database handler to update in storage
  *
  * @param Cardio $cardio
  */
 public function update_cardio($cardio)
 {
     $mh = $this->create_MySQLHandler();
     $mh->update_cardio($cardio->get_cardio_id(), $cardio->get_name(), $cardio->get_time(), $cardio->get_distance(), $cardio->get_level(), $cardio->get_date());
 }