These muscles are located in the front of your thighs and consist of the rectus femoris, vastus lateralis, vastus medialis, and vastus intermedius. Quads also help with knee extensions ...

The rectus femoris is the middle head ... a role in hip flexion in addition to knee extension.” The vastus lateralis is the lateral head, furthest from the body’s midline, says Nguyen.

On this blog, we have discussed all sorts of so-called alternative medicine (SCAM) but only rarely we scrutinize any of the many gadets and devices that are being promoted under the SCAM umbrella.