When I use rings or Trx etc for body rows, i rotate my hands so that I'm using a double overhand grip at the top of the movement when my arms are most bent, and move to a parallel neutral grip at the bottom of the movement when my arms are fully straight.
Reason being it just feels more comfortable and natural, my clients say the same.
There is nothing wrong with using a strictly parallel grip or strictly overhand grip though.
Like the pull up variations, double overhand grip body rows will be just a little bit more challenging than neutral grip body rows.
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