Alternating vs. Direct Current: Comparing TENS/STIM/EMS Units and Neuromuscular Re-education Units
M. Montoya BA BSc
The present article aims to provide a detailed comparison between Transcutaneous Electrical Nerve Stimulation (TENS), Electrical Muscle Stimulation (EMS), and Neuromuscular Re-education units. While TENS and EMS devices use alternating current to stimulate muscles, Neuromuscular Re-education units employ direct current to induce a net biochemical reaction in the body's nerves and muscles. The article outlines the advantages of using direct current-based Neuromuscular Re-education units over alternating current-based TENS/STIM/EMS units.
Transcutaneous Electrical Nerve Stimulation (TENS) and Electrical Muscle Stimulation (EMS) devices are popular therapeutic options for pain management, rehabilitation, and muscle training (Johnson & Martinson, 2007). These units use alternating current to stimulate the muscles and nerves of the body. Neuromuscular Re-education units, on the other hand, utilize direct current to create a net biochemical reaction within the nerves and muscles. This article discusses the differences between alternating current-based TENS/STIM/EMS units and direct current-based Neuromuscular Re-education units and highlights the advantages of the latter.
Differences between Alternating and Direct Current Stimulation
Mechanism of Action
TENS/STIM/EMS units use alternating current to stimulate the muscles and nerves of the body (Melzack & Wall, 1965). This type of current repeatedly changes direction, stimulating the nerves and muscles in a non-specific manner. The primary goal of TENS/STIM/EMS units is to provide temporary pain relief or muscle contractions (Watson, 2008).
Neuromuscular Re-education units use direct current, which flows in a single, constant direction. This type of current generates a net biochemical reaction in the nerves and muscles, causing them to contract and relax in a more controlled and specific manner (Bhadra & Kilgore, 2005). This targeted approach allows for more effective muscle retraining and rehabilitation.
While TENS/STIM/EMS units may provide temporary pain relief or muscle stimulation, the benefits are generally short-lived and inconsistent (Vance et al., 2014). In contrast, Neuromuscular Re-education units have demonstrated greater effectiveness in muscle retraining and rehabilitation due to the direct current's ability to elicit a more controlled and targeted muscle response (Daly et al., 2011).
TENS/STIM/EMS units may cause discomfort, skin irritation, and burns due to the alternating current's non-specific nature (Gossrau et al., 2011). Neuromuscular Re-education units, on the other hand, tend to have fewer side effects because the direct current is more focused and controlled (Kilgore & Bhadra, 2004).
Neuromuscular Re-education units employing direct current offer several advantages over alternating current-based TENS/STIM/EMS units. The direct current stimulation creates a net biochemical reaction in the body's nerves and muscles, leading to a more targeted, controlled, and effective muscle response. This can result in improved muscle retraining and rehabilitation. Additionally, direct current-based Neuromuscular Re-education units tend to have fewer side effects compared to alternating current-based TENS/STIM/EMS units.
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