There are a lot of things we read in health or fitness magazines, or see in the general media which may not apply to everyday life, or functional capacity.
Functional capacity is defined as your ability to do work. For the purposes of this post, we're considering work in the mathematical/mechanical sense of moving some load (mass) over a distance. That could be your stapler from the left side of your desk to the right side, carrying the groceries from the car, or putting 95 lbs on the bar and going overhead. These all demonstrate a certain measurable amount of work. Your ability to complete these task gives you a certain measurable work capacity.
My mother could never understand why someone would walk on a treadmill when you could step outside and actually get somewhere in the process. I feel similarly. It's better than nothing (though just) to spend 45 minutes on the elliptical, but have you trained your body to do anything productive? Will you use that motion, or anything similar, in the rest of your day? I suspect not. I suspect you would more likely, on a daily basis, to squat (ever get up from a chair?), lift something overhead (put a book on a high shelf?) or deadlift (pick up anything from the ground?).
Don't get me wrong, the elliptical machine is great for elliptical-ing, and perhaps for rehabilitation, but for most of us, it will not enable an easier time with any physical task in our day.
Most exercise media is just made for to fill up said media, and lacks true functional application. Which is fine if you just want to "sit like this" more effectively. But wouldn't our valuable time be better spent performing exercise that just might relate to the motions we're already doing on a daily basis?
Tomorrows post will address the benefits of lifting a wee bit heavy. I'm sure you already know it's functional :)