$db = JFactory::getDBO(); 
$query = $db->getQuery(true);

$sessions = $_POST['form']['Sessions']; // get the list of sessions that are selected

for($i=0;$i<count($sessions); $i++)
{
	$thankYouMessage = $thankYouMessage .  '<style>p {margin: 0}</style>' . '<h2>'.$sessions[$i] . '</h2>';
	$sql = "SELECT `{$sessions[$i]}` FROM `#__rsform_skater_sessions` WHERE `{$sessions[$i]}` !='NULL' AND `{$sessions[$i]}` !='' ORDER BY `{$sessions[$i]}`";
	$db->setQuery($sql);
	$db->query();
	$skaters= $db->loadAssocList();
	for($j=0;$j<count($skaters);$j++)
	{
		$thankYouMessage = $thankYouMessage . '<p>' . $skaters[$j][$sessions[$i]] . '</p>';
	}
}
echo $thankYouMessage;