Treadmills were originally designed to punish prisoners

Treadmills

If you are one of the 51.8 million people in the US who use a treadmill for exercise, you know there’s much pain for your muscle-and-fitness gain. On your next 30-minute jog, as you count down the final seconds, ponder whether the hard work made you a better person. Consider whether the workout would feel different if you had powered something, even a fan to cool yourself off.

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