The XS1 has a safety feature known as Bar Tilt that will unload the tension immediately during barbell exercises when the system detects a struggle by an abnormal tilt of the barbell. Another safety feature is called Stall Detection. If you stop for more than five seconds at the bottom of your range of motion or stop for 15 seconds at any portion of the lift, the system will unload and end the set immediately. 

The XS1 also has an advanced training feature known as Virtual Spotter. When engaged, like a real spotter, Virtual Spotter will assist you when you are unable to continue to move the cables. There are two modes for Virtual Spotter: Gradual and Instant. When gradual mode is selected, the XS1 will progressively reduce the tension by up to 20 pounds when a struggle is detected until your lift is moving again. Conversely, if instant mode is selected, the XS1 will instantly unload all tension and end your set if it detects a struggle.