An elliptical trainer or cross‎-trainer ‎(‎also called an X‎-trainer‎)‎ is a stationary exercise machine used to simulate stair climbing‎,‎ walking‎,‎ or running without causing excessive pressure to the joints‎,‎ hence decreasing the risk of impact injuries‎.‎ For this reason‎,‎ people with some injuries can use an elliptical to stay fit‎,‎ as the low impact affects them little‎.‎ Elliptical trainers offer a non‎-impact cardiovascular workout that can vary from light to high intensity based on the speed of the exercise and the resistance preference set by the user‎.‎user‎'‎s upper and lower body‎.‎ Though elliptical trainers are considered to be minimal‎-impact‎,‎ they are an example of a weight‎-bearing form of exercise‎.‎ They can be self‎-powered by user‎-generated motion or need to be plugged in for adjustment of motion and/or for supplying their electronic consoles and resistance systems‎.‎