Oscar Pistorius rocking his Cheetahs during the 2008 Beijing Paralympic Games (Image courtesy Duif du Toit/Gallo Images/Getty Images)

Energy is ubiquitous, which makes it a beautiful blog topic. Once you start thinking about energy as more than just oil or solar power, but rather as the input that powers all systems, a world of topics opens up for you. If you’re like me, you also start thinking about all the ways in which energy is lost. You just lost some reading this. I just lost some writing this.

For an amputee, all that lost energy can add up. Consider that people without prosthetic limbs dissipate a significant amount of energy while walking, mainly between strides, according to Steven Collins and Arthur Kuo, the developers of a micro-processor-controlled artificial foot they described in a February 2010 PLoS ONE paper. Your ankle, however, saves the day, and makes up for that lost energy during push-off, write Collins and Kuo.

You can probably guess what happens if you’re walking with a conventional prosthesis. You’re not going to benefit from that handy ankle push-off, and you’re going to expend more energy, 23 percent more, report Collins and Kuo. With that in mind, the duo from Delft University and the University of Michigan created an artificial foot that snags some of that dissipated energy and turns it into positive ankle work. Their device (not commercially available yet) trims that energy expenditure down to 14 percent, from 23 percent.

Those findings are interesting, but are there assistive devices out there that improve on the human energy equation and/or bodily performance? Like, say, the Cheetah blades that South African runner Oscar Pistorius uses to blow past the competition (but ultimately didn’t quite qualify him for the 2008 Beijing Olympics)?

After all, we’ve gotten pretty good at legally and illegally turning the energy odds in our favor, whether it be with performance-enhancing drugs, career-changing surgeries or serious training. Why shouldn’t that be the case in the world of prosthetic limbs, too?

Stay tuned for our upcoming podcast on prosthetic limbs and continue the conversation below or on Facebook or Twitter.