New Delhi, May 30 -- After work, Aditi Singh carves out 20 minutes to lie on a mat that emits a faint, steady pulse. "I started using it because I wasn't sleeping well," says the 33-year-old entrepreneur in Delhi. "Now it's just part of my routine." The device is a PEMF mat-a full- or partial-length pad threaded with coils that deliver low-frequency electromagnetic pulses through the body. Sessions are brief, typically 10 to 30 minutes. Most mats operate at modest intensities, with frequencies hovering between 1 and 30 hertz-ranges often marketed as mirroring the body's natural rhythms, though specifications vary by brand. Many layer in extras: infrared heat, red light, even embedded crystals designed as much for comfort as for effect.

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