Sitting becomes a problem when it translates into a pattern of (sedentary) behavior that often results in a lack of regular exercise. More to the point, most of the studies define sitting as a prolonged behavior with little to no movement (eg. Watching tv, working at a desk, etc.). And, to confuse things more, a relatively new study suggests that sitting for long periods is no worse for your health than standing. The study states:
"Our study overturns current thinking on the health risks of sitting
and indicates that the problem lies in the absence of movement rather
than the time spent sitting itself," said one of the researchers,
Melvyn Hillsdon from the University of Exeter. "Any stationary posture
where energy expenditure is low may be detrimental to health, be it
sitting or standing."
Associations of sitting behaviours with all-cause mortality over a 16-year follow-up: the Whitehall II study
While there seems to be confusion and a lack of consensus, I would suggest, from my own experience, that using a rower for an extended piece certainly does not qualify as a lack of movement, or, energy expenditure. And, while other studies suggest that sitting is harmful even with exercise, in my opinion, given the lack of consensus, there needs to be a more complete study that examines exercise and its potential to counteract any harmful effects of sitting as it applies to a pattern of sedentary behavior.
