Written by One of the cool aspects of the MyoWave device that measures muscle activity by converting vibration to absolute effort is the ability to determine the optimal locations on the muscle body from which to take measurements.
To find out the answer for two very commonly scrutinized muscles in the thigh we performed a semi-scientific test one recent afternoon.
We attached three vibromyography (VMG) sensors to the belly of the vastus medialis (VM) on Sara, our willing Sonostics subject, using elastic straps with a “quiet” hook-and-eye system. With much experience we had determined that Velcro straps simply make too much noise as the loops and hooks get stretched. Admittedly, we have not yet devoted any time to determining whether the frquency of that noise could be readily filtered out – a job for another afternoon.
The first sensor was affixed using an elastic strap about 3 inches above her knee. A second sensor was attached about 2 ½ inches above the first and yet a third was attached a similar distance above the first two.
Sara then performed ten squats and we monitored the effort generated by the VM during each event.
We repeated the experiment, switching the sensors to her vastus lateralis (VL) and added a fourth sensor even higher than the first three. To ascertain the level of repeatability we had her re-do the VL test, squatting an additional ten times.
The results were consistent and quite interesting and provided insight as to how we ought to advise users of this technology. We found that the lower the position of the sensor on either the vastus medialis and vastus lateralis, the greater the effort recorded.
Given all the caveats about the lack of scientific method we used in this afternoon activity, there was no doubt that – in this test with this subject at least – total amplitude of muscle effort was reduced with each successively higher placed sensor. The table below and the accompanying graph describe the correlation between distance from the knee and percentage of signal recorded:
| 3″ Above Knee | 5.5″ Above | 8″ Above | 10.5″ Above | |
| VL Test 1 | 100% | 87% | 82% | 75% |
| VL Test 2 | 100% | 85% | 75% | 73% |
| VM Test 1 | 100% | 81% | 63% |
We also compared the absolute total effort calculated by the lowest sensor on each of the VL tests (the one 3″ above the knee) and determined that the difference between the two sets of squats for that sensor was less than 4%. Obviously, we need to expand this experiment to include other subjects as well as to repeat this with Sara but we decided to share the information nonetheless.
Written by 
extremity pain such as patellofemoral syndrome (runner’s knee), a hotly debated subject in recent years has been the proficiency of the athletic shoe. Marketed to prevent and treat such injuries are a wide array of choices such as motion control, stability, gel cushioning and arch support, however in recent years both kinesiologists and orthopaedic doctors have debated whether they actually prevent or cause injuries in the lower legs. A 
Single VMG sensors were attached to my vastus lateralis, biceps femoris and the sartorius muscles using an elastic strap. I then performed 6 one-legged squats with inward rotation of the knee while wearing inexpensive running shoes. The graph displays the averaged level of effort expended during the 6 repetitions. The red line represents the Sartorius; the blue the Vastus Lateralis.
Two weeks ago Sonostics added two new software architects (Adam Smallcomb and Tim Cortesi) who are taking the 
Just after we moved, Senator Kirsten Gillibrand dropped in to hold a news conference, 
he vastus lateralis and the biceps femoris using an elastic strap. The subject was then asked to perform 10 squats. Upon completion, the amplitude of effort generated simultaneously during the exercise by these two muscles was compared through the squatting and rising portions. The exercise was then repeated for the uninvolved leg.
1. it seemed that even at rest, between squats, the subject was clearly favoring his reconstructed leg, as evidenced by the amplitude of his uninvolved quad to support the standing position; and
We chose to deploy the accelerometer in “differential mode”, meaning that we could take advantage of the most sensitive setting the sensor offered which necessitated doubling some of the components and the wires. It was a tradeoff we were happy to make but it did impact the size of the end product.
The end result is the BPS-IIm mini-transducer, which deploys the accelerometer in its own, much smaller, enclosure, tethered via four very thin wires (so that we can maintain our differential mode) to a secondary enclosure that now houses the necessary filters and amplifiers.
At the heart of Inbound Marketing is an understanding of what our potential audience was looking for and providing them with web content worth reading. We analyzed the top search terms that visitors to our website used to find us over a period of months and found that 4 out of the top 10 included some reference to the “length tension relationship” of muscles.
We’ve got a long way to go but since we changed our website from a static tombstone to one with new content several times a week we can see the results. Our new pastime is watching the New Prospects list grow, analyzing how often a given visitor hits us and to what pages they gravitate. That enables us to further tailor what appeals to the folks we are trying to reach. Make the top of the funnel large enough and make that funnel an interesting place to visit and you can be assured that customers will emerge out the bottom.
Keep In Touch