If you're needing a rowing variation that keeps stress on the lumbar to a minimum, try this.
If you have access to leg-raise straps and haven't used them for back work, you're missing out. Especially if you're one of those lifters who can't feel his lats working due to having strong biceps or a tendency to pull with his arms during back work. To really engage your lats, get your elbows behind you. Focus on the contraction.
Fight perma-slouch by moving your thoracic spine into extension. Hang out in one spot for as long as you feel a stretch. As you feel it fade, shift the roller down your spine.