The air resistance is at max. I move forward until my knees are bent almost as far as possible, my arms straight, elbows extended and then pull back until my le

The air resistance is at max. I move forward until my knees are bent almost as far as possible, my arms straight, elbows extended and then pull back until my legs are nearly straight, my hands at my chest, my biceps tight and the chain nearly at the limit. I'll try what you suggest. Maybe all the machines I've used (about 6 of them) at various gyms are mistuned/broken in some way. These machines don't get the best of care in a gym setting. I didn't say it wasn't a good workout or that it doesn't work me out well; in fact I said the contrary. But it doesn't challenge me in any particular way while it does seem to challenge some apparently healthy persons(i.e., trim, muscular shape, young, etc.). I've read the machines' instructions, seen others use the machines, live and on videos, and, while rowing is not difficult for me, it does provide variety. But I was wondering why rowing wasn't more difficult. Contrast with my recent return to swimming: I swam much of my life but left it about 15 years ago for other sports. I'm trying to get back in swim shape and, while my heart has no problems, I badly want more air faster! Rowing is graceful b/c air is readily available. But in swimming you have only a moment each stroke to breathe. And parts of swimming are anaerobic (sprints, first ~10 seconds of a race). So in swimming I see a clear personal limit to extend.