Earth & Performance Series - DOMS and Recovery, Continued

We now return to the oh-so-dreaded DOMS.. In 2019, Müller and colleagues published a study that extended earlier research on grounding and recovery. They wanted to see if sleeping grounded could improve recovery after intense eccentric muscle loading.

Participants were assigned to either a grounded sleeping group or a sham-grounded group over a 10-day recovery period. Each had completed a single bout of intense downhill treadmill running. To track recovery, tests were done before the intervention and again on days 1, 2, 3, 5, 7, and 10. These included muscle soreness measured by a visual analog scale (VAS), blood levels of creatine kinase (CK), strength via maximum voluntary isometric contraction (MVIC), and lower limb performance through counter movement jumps (CMJ) and drop jumps (DJ).

MVIC involves pushing against an immovable surface to measure raw muscle force. CMJ and DJ are used to test explosive leg power. CMJ starts from a static squat, while DJ involves dropping from a platform and jumping on impact.

Before the main study, two pilot tests were also conducted. One tested the effect of conductive sheets on body voltage. The other collected blood samples to measure inflammation markers in four main study participants.

The main study included 22 participants. Twelve slept grounded using a conductive sheet connected to a grounded wall outlet. Ten slept on a sham-grounded sheet. After the intervention, both groups showed performance declines and elevated soreness and CK levels. But the grounded group showed less of a drop in MVIC and CMJ and a smaller rise in CK. This suggests grounding helped preserve muscle function.

Further blood analysis revealed something interesting. In the sham-grounded group, erythrocytes, hemoglobin, and hematocrit increased, while red blood cell volume (MCV) dropped. This didn’t happen in the grounded group. These changes suggest that exercise-induced blood trauma—like squeezing red blood cells through tight vessels—was worse in the ungrounded group.

Why does that matter? Because intense exercise causes inflammation and mechanical stress on red blood cells. The ungrounded group seemed to experience more of that stress. Grounded sleep appeared to protect red blood cells and stabilize key oxygen-carrying metrics.

That difference could also explain the higher CK levels in the ungrounded group. Blood becomes more viscous under stress. Grounding may counter that by improving blood flow and reducing inflammation. That idea matches previous findings in the Earth & Heart series.

The researchers also looked at markers tied to immune activation. In four participants, they tracked changes in molecules like sP-selectin, IP-10, MIP-1α, and MIP-1β. These are involved in white blood cell signaling and inflammation. The grounded group showed a consistent drop in sP-selectin—around 20% lower than baseline. IP-10 and the MIPs were also reduced in grounded sleepers.

This matters because these markers rise during immune activity following muscle damage. TNF-α and IFN-γ drive up IP-10, which recruits killer cells to clean up dead muscle tissue. Reducing this signal may calm excessive immune activity and promote faster, cleaner regeneration.

Chemokines like MIP-1α and MIP-1β come from macrophages, which flood damaged muscle to clear debris. These were also lower in the grounded group, suggesting less inflammation overall.

The consistent reduction in sP-selectin supports the idea that grounded sleep reduces clotting signals and inflammatory burden. It also may support better angiogenesis, or blood vessel repair and formation.

Taken together, these data suggest that grounded sleeping helps the body manage the early inflammatory phase of recovery more efficiently. Less damage, more control, better repair. That’s now two studies showing similar effects.

One pilot study also confirmed that grounded sheets reduced body voltage dramatically. Body potential dropped to around –0.2 V when grounded, compared to –81.9 V with the sham setup. This supports earlier work by Applewhite showing that grounding equalizes body voltage with Earth when a conductive connection is used.

Across these three studies, we now see a clear trend. Grounding, whether through direct Earth contact or through conductive sheets, can support recovery by reducing soreness, stabilizing muscle performance, and lowering inflammation. It may also protect red blood cells and reduce immune overactivation.

The body appears to dampen the catabolic impact of exercise when grounded. And one way to track this is through blood urea nitrogen, a marker we’ll touch on next. Because recovery is only half the story. The next study asked what happens if you ground yourself not after training, but during it.

As always, if you’re interested in learning more about grounding, check out Earth & Water.

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