Do contracting muscles emit electric fields?

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Discussion Overview

The discussion revolves around the question of whether contracting muscles in the human body emit electric fields, exploring the sources of electric fields in the body, and the sensitivity of EMF meters to these fields. It touches on concepts from electromyography (EMG) and the effects of the human body on electromagnetic fields.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions what in the human body emits electric fields, suggesting muscle activity as a possible source.
  • Another participant discusses the concept of conducting radio energy and how proximity to devices like CRTs can affect electromagnetic emissions.
  • It is noted that detecting muscle noise through EMG is challenging, with references to the historical use of galvanometers in ECG instruments.
  • A participant suggests that the readings from the EMF meter may be influenced by external sources, such as AC mains wiring, rather than originating from the body itself.
  • Concerns are raised about the reliability of EMF hazard assessments and the calibration of measuring devices.
  • One participant expresses frustration with the presence of pseudoscience in the thread, indicating a desire for more rigorous experimentation.

Areas of Agreement / Disagreement

Participants express differing views on the sources of electric fields detected by EMF meters, with some attributing the readings to external factors while others consider the possibility of muscle activity. The discussion remains unresolved, with multiple competing perspectives present.

Contextual Notes

The discussion highlights limitations in understanding the frequencies involved in the measurements and the challenges in accurately assessing electromagnetic fields. There is also mention of the complexities involved in EM hazard assessments.

jaketodd
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I bought an EMF meter that can discriminate to electric fields, and it is highly sensitive to the proximity of my body. What is it in the human body that emits electric fields? Is it muscle activity? Maybe many things in the body? Thanks.
 
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People conduct radio energy. They pick it up from one place and retransmit it.
For example, if you are sitting close to a CRT (old TV or oscilloscope) you will be transmitting lots of EM.
 
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.Scott said:
People conduct radio energy. They pick it up from one place and retransmit it.
For example, if you are sitting close to a CRT (old TV or oscilloscope) you will be transmitting lots of EM.
We don't do anything different compared to any other bag of saltwater our size... :smile:

jaketodd said:
I bought an EMF meter that can discriminate to electric fields, and it is highly sensitive to the proximity of my body.
Go out into the middle of an open field and try it again. Most likely you will not see anything. If in your test you are in your house near AC Mains wiring, the AC voltage (current) from your parasitic capacitance to that wiring is probably what your EM meter is sensing.
 
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Baluncore said:
Detecting muscle noise, EMG, is difficult.
ECG instruments are commonplace and not too high tech. They used to consist of nothing more than sensitive galvanometers, in the past. The electrical activity of the heart is measured by placing electrodes (pads) at a number of places on the torso. They record signals in the order of a few mV but that is very different from a radiated field. Is EMG a different thing, apart from the muscles it looks at?

The OP is referring to an EMF meter which, afaiaa, is for assessing the potential harm from exposure to EM fields. What he's been measuring / detecting will almost certainly be the effect of the presence of his body on the fields that are there anyway. An FM radio can be affected greatly by the presence of a human - either improving or worsening the signal strength, depending, in the same way as wiggling the whip antenna about. The body acts like a piece of metal of similar size and re-radiates signals in the vicinity.

Without knowing about the frequencies involved, it's hard to comment usefully on what he's seeing but there's not much chance of it coming from his body if a simple hand held device can register it.

PS EM Hazard assessment is a bit of a black art and getting relevant and meaningful readings of fields is pretty hard. Not least, the antenna / probe needs to be well calibrated and characterised if the results could be accepted in a court of law when someone claims Industrial Injury!
 
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This thread has become a magnet for pseudoscience nonsense posts (which have been deleted). @jaketodd please do the "outstanding in your field" experiment that I suggested. Thank you. Thread is closed.
 
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