add_action('rss2_item', 'f3isotope_rss2_item');
function f3isotope_rss2_item() {
if (get_post_type()=='backblast') {
$fields = array( 'q', 'workout' );
$post_id = get_the_ID();
foreach($fields as $field)
if ($value = get_post_meta($post_id,$field,true))
echo "<{$field}>{$value}\n";
}
}
