In 1935 there were nearly 7 million farms. At that time, nearly all would have been "family" farms. Even though we were "industrialized" back in 1935, much of the labor required on a farm, or elsewhere for that matter, would have been done manually. Really, unless you were extremely well off, you had no need for exercise. Sport perhaps, but people weren't going to the gym for Spin classes three times a week.
Since that time, the number of farmers has decreased, (In 1997 there were 1.7 million) as our obesity levels have gone up. Our parents and grandparents didn't have to think so much about adding physical activity in to their lives because it just was part of their lives.
I grew up on a farm. It was a tiny organic vegetable farm commune. (before the days of CSA's and organic Target's) I never really thought about a need to exercise, because it was part of the daily life on a farm. Especially when you add in that we had to pump our own water, haul wood for heat, and a variety of other fun things that go with no electricity, no running water, and living in the middle of nowhere. Everyone around me lived on farms too. There was cow milking, throwing around hay bales, and chasing pigs. It just wasn't part of our lives.
I don't live on a farm any more, my job involves sitting at a desk. I'm struggling with making time to be physically active in my life. It doesn't seem like something that should take so much work. Yet when you look at the statistics, both obesity and societal change wise, it makes perfect sense. We got here over generations of changing to the way we live our lives.
I worry about my daughter's health, and how she may struggle with weight and body image the way I have. (I'm not the only one) I realize that the best thing I can do for her is to make the time, to make that something that she sees me doing all the time. Not just for my own health, but her future health. This cycle of inactivity started long before me, but I do my best to make sure it stops with me.