<form action="<?php echo $_SERVER['PHP_SELF'];?>" method="post">

<?php $sports = array("Basketball", "Football", "Handball");?>

<form action="<?php echo $_SERVER['PHP_SELF'];?>" method="post">
    <input type="hidden" name="serializedData" value="<?php echo serialize($sports);?>">
    <input type="submit" name="okButton" value="OK"><br>
</form>

if(isset($_POST['okButton'])) {
   $sports_new = unserialize($_POST['serializedData']);

   // Show array
   for($i = 0; $i < count($sports_new); $i++) {
                    print $sports_new[$i]."<br/>";
   }