Shipping protection

After 40 minutes grounded, the high-frequency band of heart rate variability, a standard marker of the body's rest-and-digest system, rose 63%, compared with 33% during sham sessions. Overall heart rate variability rose 50% versus 20%.

Ten healthy adults were grounded for two hours. Blood samples showed their red blood cells carrying, on average, 2.7 times more negative surface charge (zeta potential), and clumping together significantly less.

22 people did an intense downhill treadmill run, then slept on real or fake grounding equipment for 10 nights. Neither they, the testers nor the analysts knew who was grounded. The grounded group lost less jump height and leg strength and had a smaller rise in creatine kinase, a blood marker of muscle damage.

In a separate study, 32 men grounded for 4 hours a day after 200 knee bends kept that muscle-damage marker flatter, though soreness was similar in both groups.

In a randomized, double-blind trial, 60 adults slept on either a grounding mat or an identical non-grounding mat for 31 days. The grounded group's sleep-quality and insomnia scores improved, and their total sleep time, tracked on a wrist device, increased compared with the control group.

In another trial, 16 massage therapists grounded for 4 weeks reported less fatigue, anxiety and sleep disturbance.

12 people with sleep complaints slept grounded for 8 weeks. Their night-time levels of cortisol, a stress hormone, fell, and their 24-hour cortisol rhythm moved toward a typical daily pattern. Nearly all reported sleeping better and feeling less stressed and in less pain.