... quietly 2.Physical therapy for arms and legs 3. Useful training for paralysis muscle 4. Aerobic exercise Mini Auto Exercise Bike1 ... ,60rp/m,70rp/m,can be adjusted accordingly2. Time:5 different choices for time-setting ,3 min,6min,9min,12min ,15min3 ... released in one minute,the motor will stop automatiocally. Useful training for paralysis muscle mini bike