Planning a Session 1) Hi in this section, we are looking at planning a training session. It may seem that planning a training session is a bit complicated but we want to show you it's not rocket science. In previous lessons we have learned that stimulation intensity depends upon three things - frequency, current and pulse width. We also learned that the energy is delivered to the muscles as a series of bipolar pulses of electricity. It is the width, height and frequency of these pulses that count. 2) We've learned that the frequency of the stimulation can have a number of effects depending on its value. For example, higher frequencies, tend to build strength in the muscles being stimulated and lower frequencies can build endurance, help muscles to relax or assist with wound healing. If we want a strong, smooth, muscle contraction for FES Cycling we typically will need a frequency of 20 Hz or more to enable this. 3) The frequency of stimulation being used, selectively activates certain muscle fibre types. Hopefully you've downloaded these related sheets for future reference. 4) OK that’s the effects of Frequency. With respect to current and pulse width, from experience you can gain a good idea of the stimulation parameters that are going to be needed in a particular case. For example, for a person with complete spinal cord injury, we can expect to be using current values in the range 40 to 90 mA, and pulse width values in the range 250 to 500 µs. For Stroke, Brain injury and incomplete spinal-cord injuries, sensation may limit strengths of contractions. We might then expect to use a lower intensity of stimulation because the user may well be able to contribute active cycling also. Whilst we've been able to give general guidelines based on the effect you want to achieve, an individual approach is required. 5) However much we try, we can't give a set of stimulation values that will work in all situations for all clients. There are some general rules that will apply across the board but for best results some individual adjustments are essential 6) We are all familiar with the concept of recycling - something that has been used once can be re-purposed and used again. The RehaMove system has something called a Template. This goes as far as possible to balance some of the general rules about FES we
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have learned about with the need for individuality. We can give each user a rational starting point by using templates. A template represents a reusable starting point for a user - they embody some of the knowledge we have learned so far. 7) This slide provides an overview of six templates that are provided for use by spinalcord injury clients. If you scan this list, you'll notice that each template suggests session times, frequency settings and pulse width ranges. Notice how the templates that aim for muscle power generation are short in time and tend to use higher frequencies. Meanwhile those templates aimed at endurance building are longer in duration and use lower frequencies. A template does not take away all the need to personalise the stimulation settings. It is still necessary to select suitable current values and choose a level of cycling resistance. We will see how to do all of this in detail in later lessons. Notice there is an item called Ramp which is shown in the table. Each time a muscle is activated by FES it is being subjected to a train of pulses. Up until now we have described the pulses as having a fixed pulse width. Well I told a little lie, because each time a muscle is activated we have the opportunity to vary the pulse width a little bit. If the Ramp number is 0, then the pulse widths are generated at the default level right away. If the Ramp number is 3, for example, then the pulse widths start with a small pulse width and gradually increase to their default value. This can help in cases of spams to damp down the strength of contraction a little and produce a smoother cycling action. 8) Here are the Template details for Stroke and 9) .. General purpose training. I should say again that the RehaMove unit does not force you to use any of the templates but many people find them a useful starting point. You can download these sheets for reference. 10) Where do we find the templates? Well they are available every time you create a new training profile.
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From the User Screen press “New Profile” , then select “RehaMove Arm” or “RehaMove Leg” depending on the body part you are wanting to train. Then choose “Adaptive” or “Constant” training mode. 11) The next screen asks for you to choose “Bilateral” (meaning both left and right limbs) or “unilateral” (one limb only). Here we assume that Bilateral has been chosen. Now when we press the Next button we have an opportunity to select from our parameter templates. We then select which template group we want - SCI, Stroke or Other 12) Within each group are a number of templates - the ones we showed in the tables a moment ago. By rotating the control knob we can select from the available templates and use one. Here the selected program template is “Endurance Motor Incomplete” We can either accept the general parameters as outlined in the tables earlier or we can press the “Individual” button and adjust any of the parameters as necessary for a particular situation. Once we progress beyond this screen we must set the current values for the muscles we are stimulating. 13) When we introduced the FITT concept of exercise in an earlier Chapter, we pointed out that planning a sessions boils down to thinking about how often to exercise, how hard to exercise and for how long. 14) Our baseline of advice for FES Cycling has been to use sustainable active cycling three times per week against resistance. Typically for 20 to 40 minutes per session. 15) Imagine you are on the RehaMove bike and a session has started. During a short warm up, the bike moves the legs passively at a manually set cycling speed. Once the FES starts the user can adjust the Gear resistance and the target cycling speed to achieve during the exercise. Whether a template or an individual programme has been created the Frequency and the Current values for each muscle have already been set to generate a strong muscle contraction. They may be adjusted if desired during a session. With almost every client we have used Adaptive Mode where the pulse width is automatically varied to try and get the user to cycle at a target cycling speed against the chosen level of resistance. This target cycling speed is always higher that the passive Page 3 of 4
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cycling speed. The software automatically tries to keep the user at the target cycling speed but it will only increase the pulse width up to the maximum value set by the programme. 16) Most new users will find that the muscles fatigue quickly and despite being in a low gear active cycling may only be possible for a few minutes. This active cycling time will increase gradually and eventually it is likely that the gearing resistance can be increased. 17) The RehaMove software has a Period feature that can automatically pause the stimulation allowing the muscles to recover a little. 18) By using the Period breaks it is sometimes possible for the user to do more active exercise in the sessions time despite muscle fatigue. 19) As we have seen, session management can follow some general guidelines but ultimately needs to be fine tuned to the individual. For example, when leg spasms are a problem one strategy could be to lengthen the warm up period and add as small amount of FES during the warm up period. We have learned how the Period feature can really help when muscle fatigue is an issue. Finally, remember that we don’t need to exercise intensively to get health benefits. Volume and persistence is what counts. 20) As with other lessons, you might want to download the provided sheets for later reference. That’s all for this lesson.
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