Technology guide
Tesla and power in muscle stimulation
The tesla is the unit expressing the strength of the magnetic field of an EMT device. What does this figure mean and how should you read it on a technical data sheet?
What is a tesla?
The tesla (T) is the International System unit that measures the strength of a magnetic field. On an EMT device, it indicates the strength of the field produced by the applicator.
Why it matters
By varying very quickly, the magnetic field induces an electrical current in the muscle. The stronger and faster the field, the stronger this current and the more muscle fibres are recruited. This is what makes it possible to achieve supramaximal contractions.
More is not always better
According to the source, the effect increases with strength up to a plateau, after which the gains become small: once almost all fibres are recruited, increasing the field further brings little and increases heating. The BodyShape III works at 1.9 Tesla.
Reading a technical data sheet
Strength alone is not enough: also look at the pulse duration (260 microseconds on the BodyShape III) and the frequency (150 Hz). Ask for the manufacturer's documentation and a demonstration to judge the intensity of the contractions.