The Life Fitness X8 Elliptical Cross-Trainer Electronic Adjustable Stride Cross-Trainer offers you the ultimate in customization and comfort with features such as on-the-fly electronic stride adjustments and an even lower-impact ellipse motion. Using Life Fitness' revolutionary SelectStride™ technology, the Life Fitness X5 Ellitpical Cross-Trainer allows you to adjust the stride length for different-sized users in the household or to target different muscle groups.