Keiser Functional Trainer

The Keizer Functional Trainer of the Infinity Series is a pneumatically driven strength machine for full-body functional training, covering applications ranging from targeted rehabilitation to professional elite sports. The pneumatic resistance system generates smooth, shock-free resistance—regardless of movement speed, direction, and angle—thus differing fundamentally from conventional weight-based cable pulley systems.

Shock-free pneumatic resistance for joint-friendly, multi-planar strength training in a compact footprint

Since compressed air as a resistance medium has no inertial mass, the abrupt load peaks at the reversal point that act on joints, tendons, and connective tissue with conventional weight stacks are eliminated. This biomechanical advantage makes the Infinity Series equally suitable for gentle load building in aftercare and for high-intensity athletic strength training. The resistance can be precisely adjusted in increments starting at 0.1 kg, enabling continuous, stepless progression without large weight jumps—a decisive advantage in both rehabilitation and performance-oriented conditioning. The symmetrical dual-arm arrangement allows both sides of the body to be loaded independently or in combination, so that sport-specific, multiplanar movement patterns can be performed in a single, space-saving system without the need for multiple specialized stations.