EMS devices can be harmful if used with high-intensity exercises. This combination increases the risk of rhabdomyolysis. It’s a condition where pieces of damaged muscles reach the bloodstream and cause kidney failure.
It’s a rare condition, though, and highly preventable. So, to be safe, conduct EMS sessions with trained professionals whenever possible. Drink plenty of water afterwards. Always use your EMS devices in moderation, and avoid using it while doing heavy workouts or training. Finally, follow the instruction manual. Pregnant women and people with defibrillators or pacemakers should steer clear from EMS devices as well.