Riding the RT300 FES Bike

Tuesday (10/14/08) was an exciting day in PT. It was my first time using the FES bike with my legs.  I was only able to last about 20 minutes; the muscles in my legs have atrophied after such a long period of disuse that, even with the e-stim, they don't have enough strength to continue working long before fatigue sets in.  Cara, master of informative analogy, likens it to a marathon – without training, a runner's muscles might be able to last short distances, but can't maintain a running pace through the entirety of a marathon.  Our goal, for now, is to build up the amount of time I can sustain viable muscle contractions while using the bike. 

Using the RT300 Bike is one of the central elements of the ICSCI therapy program.  The repetitive motion of the legs pushing the pedals helps to re-establish neural pathways in the spinal cord so the electric pulse of messages can travel between the brain and the body, facilitating communication and allowing the brain to control parts of the body.

The bike is a sophisticated, multi-faceted piece of equipment created by Dr. John McDonald, PhD., M.D., based on Patrick Rummerfeild's work.   It has a built-in computer system, running Windows Mobile on what appears to be some flavor of Compaq hardware, with a Bluetooth Internet connection.   Therapists are able to program patient-specific session parameters remotely, via Web browser, or through the touch-screen interface on the bike.  

One of the really great features of this exceptional piece of equipment is that it monitors and records therapy session data such as amount of stim used, amount of energy expended, session time, distance traveled, and several other variables.  It uploads the information to a database to track user progress.  Therapists and users can log into the Web interface and generate reports that list statistics and create graphs to illustrate progress over time. 

Cara attached electrodes to my quadriceps, hamstrings, and glutes, and took the leg rests off of my chair.  I pulled up to the bike, and she and Keena set my feet on the foot plates and strapped my legs in.  They attached the electrodes on my legs to the blue wires that plug into the onboard computer. The bike itself controls the e-stim, rather than a separate Empi unit.

Cara (who is always amazingly well-prepared for everything) had already programmed in all my settings, so she just logged me in to the system and pressed the big green “Go” button on the touch screen.  

The bike started up in “passive therapy” mode, which is used as a warm-up period.  In passive mode, no stim is sent to the muscles; the mechanical device inside the bike turns the pedals, usually for a period of three to five minutes.  As the pedals began to turn and my legs began to move, I just watched.  It was almost surreal, watching my own legs pedal away, moving in a manner I hadn’t seen for half a lifetime.  

It was almost a sensory overload for me.  I’m not accustomed to that much input, and it was almost overwhelming.  For the first few minutes, it consumed my brain power – in fact, I had to excuse myself from a conversation with Cara because the sheer strangeness of the experience usurped my attention and seemed to short-circuit my thought processes and I was having difficulty following what she was saying.

I can hardly describe the sensation.  The closest I could get, at the time, was “floaty”.   Perhaps not the best word choice – words like “floaty” are often used to describe the lightheaded sensation that occurs during a rapid drop in blood pressure that often precedes loss of consciousness.  Cara, who was particularly wary of adverse effects during my initial biking session, was alarmed by my description, until I assured her I meant my legs, not my head, felt floaty.

After five minutes, “active therapy” mode started; the e-stim kicked in, causing the muscles in my legs to contract and push the pedals.  I could discern between the active and passive modes, but I’m not sure how.  How each mode felt to me, of course, is much different than it would feel to someone with unimpaired sensation, so there was not as drastic a difference between them for me, thus making it difficult to pinpoint what had changed.  I will work on isolating the difference and describing it to myself during my next biking session, so I can more accurately convey the experience in future posts.

Though I was able to last only 20 minutes during my Tuesday session, Cara tweaked some parameters and I went for 30 minutes on Wednesday.  We’re working up to doing an hour at a time.  Cara said that an hour using the bike is equivalent to 5,000 steps, which is about half the number walked daily by the average person.