The different Twin Stim 2nd Edition modes

The Twin Stim 2nd Edition is a hybrid TENS/EMS pain management unit. As such, it has some modes that are exclusive to EMS, and others that are exclusive to TENS. This device has three EMS modes (Constant, Synchronous, and Alternate), while the TENS modes are five (Burst, Normal, Modulation, Strength Duration 1, and Strength Duration 2). In order to better understand the following specifications, it is important to keep in mind that for the Twin Stim 2nd Edition, the On Time and Off Time are adjustable from 2 to 90 seconds and 0 to 90 seconds respectively, both with a 1 second/step. The Ramp Time is adjustable as well, from 1 to 8 seconds (1 second/step). 
EMS modes
  • Constant (C mode) provides constant stimulation based on setting value; only pulse duration, pulse rate and timer are adjustable in C mode.
  • Synchronous (S mode) offers simultaneous stimulation of both channels. The On Time includes ‘Ramp Up’ and ‘Ramp Down’ time. As a result, the On Time setting should be more than twice the Ramp time in S mode.
  • Alternate (A mode) consists of stimulation of channel 2 taking place after the first contraction of channel 1 is complete.  The On time setting should be more than twice the Ramp Time in A mode, and the Off Time equal or higher than the On Time.

TENS modes
  • Burst (B mode) features adjustable burst rate (0.5 to 5Hz) and pulse width (50 to 300us), and fixed frequency (100Hz).
  • Normal mode in TENS is equal to Constant mode in EMS.
  • Modulation (M mode), also known as Sweeping, is a combination of pulse rate and pulse duration modulation. Rate and duration are cycled through automatically in 50% decreases from their original settings one after the other every 0.5 seconds. In M mode, pulse rate (2 to 150Hz) and pulse duration (50 to 300us) are completely adjustable. 
  • Strength Duration 1 (SD1 mode) combines automatic modulation intensity and pulse duration in a 40% range. The intensity decreases by 40% as the duration increases by 40%, and then the other way around in the following 5 seconds. Pulse rate (2 to 150Hz) and duration (50 to 300us) are adjustable in this mode.
  • Strength Duration 2 (SD2 mode) is basically the same as SD2 mode, except that it works in a 70% range.

Related Read: Twin Stim Plus 2nd Edition Product Review