The core waist-exercising function remains fully functional; you can use a phone stopwatch for timing needs.
FlexiHome Spine Twist and Stretch Trainer, Detachable Back Stretcher Machine, Adjustable Exercise Equipment for Lower Back Pain Relief, Spine Decompression, Leg Stretching & Core Activation
Spine Twist and Stretch Trainer, Detachable Back Stretcher Machine, Adjustable E
3 in 1 Spine Twist Stretcher& Stair Stepper & Waist Trainer Crawling Training Machine Noiseless Spine Twist Stretch Trainer with Adjustable Hand Grips LED Display Steel Frame Full Body
Crawling Machine Spine Twist & Stretch Trainer Effective Waist & Spine Workout, 3 Adjustable Height LED Counter 100kg Capacity, Detachable, for Full-Body Workout(Black)
