Is it doable to assign custom field values to php array? Something like
{exp:channel:entries channel="challenges" require_entry="yes" limit="1" cache="yes" refresh="60"}
{reverse_related_entries id="week_stats"}
<?php
$i = 1;
$stats[$i]['fat'] = "{body_fat}";
$stats[$i]['weight'] = "{weight}";
$stats[$i]['biceps'] = "{bicep_left}";
$stats[$i]['chest'] = "{chest}";
$stats[$i]['thigh'] = "{thigh_left}"
$i++
?>
{/reverse_related_entries}
<?php print_r($stats);?>
...
...
...
{/exp:channel:entries}