Yes, it's like a treadmill stair stepper! Almost like a mini escalator, and that thing is the fucking devil! LMAO. If you want a good workout that thing will have you sweating hard in just a few mins.

Stationary jogging will definitely put quite a bit of strain on your Achilles Tendon so be very cautious with that and don't overdo it. If you are looking for a way to break a sweat without really pounding on that tendon maybe try an elliptical machine (if you have a gym membership). Otherwise a great at home workout is yoga, that is not only easy on joints and tendons but will also strengthen them. Plus you can youtube that or download a yoga app for free.

My fiance is a yoga teacher and she breaks me off when I come to her power yoga classes, that shit is no joke ;)