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What does a TENS unit do?
Can it really make your muscles relax?
A TENS unit, or a Transcutaneous Electrical Nerve Stimulation device, is typically a hand-held unit that caters to different therapeutic needs with the main goal of managing or reducing pain symptoms in a specific area of the body. They often have multiple settings and adjustable features that allow users to control variables such as pulse width, intensity, and frequency to more effectively alleviate diverse forms of pain. Based on this, a TENS unit can be an effective treatment for pain and a viable alternative to more invasive approaches and medications.
How does a TENS unit work?
A TENS unit operates by transmitting low-voltage electrical currents through surface electrodes attached directly to the target tissue area. The underlying principle behind its functionality is not fully understood, however, the most accepted mechanism is based on the Gate Control Theory of pain. Initially proposed by Melzack and Wall in 1965, this theory suggests that pain perception can be diminished when non-painful input (like the electrical pulses from a TENS unit) competes with the existing pain signals. This effectively “closes the gates” to the painful input in the nervous system, thus inhibiting pain messages from reaching the brain. This mechanism is what likely makes TENS an effective tool in pain management and completely differs from the approach of most pain killers and opioids.
Does a TENS unit make your muscles relax?
Studies such as those by Taylor in 1997 have shown that the application of TENS can reduce passive tension in muscles following repeated contractions or passive stretching. This relaxation effect may stem from modifications in the muscle’s viscoelastic properties, as suggested by Fukaya in 2021. Meanwhile, other studies indicate that the use of TENS with stretching may not increase flexibility beyond what stretching alone can achieve, as noted by Maciel in 2008. Therefore it seems advisable to combine TENS use with other exercise or stretching programs to attain the best results in the long term.
How can I incorporate a TENS unit into my routine?
TENS units are readily available without a prescription, making them accessible through most pharmacies and online platforms. It can be used as needed for pain, with effects often being immediate and potentially lasting for hours after the session. Therefore the best use of a TENS unit might be as an adjunct for pain modulation after particularly intense training sessions or physically stressful days.
While TENS units are an excellent option for temporary relief, they should not be relied solely upon as a long-term solution. Ideally, they should serve as a supplement to other treatments aimed at addressing the root causes of pain or dysfunction. It is also advised to use TENS in short intervals or incorporate 10-minute breaks if administering for over one hour.
By understanding the mechanism of TENS units and learning how to effectively use a unit, individuals can enhance their quality of life and training through improved pain management. Results can be significantly improved when combined with other treatments to better understand your pain mechanisms and current functional or training level.
< Recommendation by Our Experts>
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Combine for Optimal Results: Use a TENS unit in conjunction with exercise or stretching programs to maximize muscle relaxation and pain relief. This complementary approach can enhance flexibility and support long-term improvement in managing discomfort.
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Use Judiciously: Incorporate TENS into your routine as a supplementary tool for pain modulation, especially after intense physical activities. Remember to take regular breaks and avoid relying solely on TENS for long-term pain management.
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Understand and Explore: Educate yourself on how TENS units work to effectively integrate them into your pain management strategy. Seek to understand your pain triggers and consider a comprehensive approach that addresses the underlying causes, ensuring an improved quality of life.
< Reference >
- Teoli D, An J. Transcutaneous Electrical Nerve Stimulation. In: StatPearls. StatPearls Publishing; 2024. Accessed April 22, 2024. http://www.ncbi.nlm.nih.gov/books/NBK537188/
- Sluka K, Smith HS, Walsh DM. Transcutaneous Electrical Nerve Stimulation (TENS). In: Neuromodulation. Elsevier; 2009:335-344. doi:10.1016/B978-0-12-374248-3.00025-2
- Melzack R, Wall PD. Pain mechanisms: a new theory. Science. 1965;150(3699):971-979. doi:1126/science.150.3699.971
- Taylor DC, Brooks DE, Ryan JB. Viscoelastic characteristics of muscle: passive stretching versus muscular contractions: Medicine & Science in Sports & Exercise. 1997;29(12):1619-1624. doi:1097/00005768-199712000-00011
- Fukaya T, Nakamura M, Sato S, et al. Influence of stress relaxation and load during static stretching on the range of motion and muscle–tendon passive stiffness. Sport Sci Health. 2021;17(4):953-959. doi:1007/s11332-021-00759-2
- Maciel A, Câmara S. Influência da estimulação elétrica nervosa transcutânea (TENS) associada ao alongamento muscular no ganho de flexibilidade. Rev bras fisioter. 2008;12(5):373-378. doi:1590/S1413-35552008000500006
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