Adequate recovery is essential in order to achieve better performance in any sport. Muscle fatigue is a result of changes at the level of the muscle, such as micro tears, depletion of creatine phosphate, accumulation of metabolites, mismatch of oxygen supply/demand or even central nervous system fatigue. The question is, is TENS an effective method to enhance the rate of recovery after exercise? Based on 10 different articles I reviewed, the results are rather disappointing
|Milne 2001||negative review of 5 trials of TENS for chronic low back pain|
|Johnson 2007||positive review of 38 trials of TENS for chronic musculoskeletal pain, “effective”|
|Nnoaham 2008||inconclusive review of 25 studies of TENS for chronic pain|
|Khadilkar 2008||inconclusive review of 4 trials of TENS for chronic low back pain|
|Walsh 2009||inconclusive review of 12 trials of TENS for acute pain|
|Hurlow 2012||inconclusive review of 3 trials of TENS for cancer pain|
|Vance 2014||mixed review: “it’s complicated”?? but promising|
|Chen 2015||negative review of 18 trials of TENS for knee osteoarthritis|
|Desmeules 2016||inconclusive (but discouraging) review of 6 trials of TENS for rotator cuff tendinopathy|
How does TENS work?
Pain is a result of alarm systems that reach your brain. These alarms go off way too loud and way too often, sometimes even without tissue damage. The brain decides what hurts and what doesn’t. The TENS machine blasts the nervous system with “sensory white noise”, and by stimulating the nerves in this way it distracts the brain (temporarily) from pain. Unless you turn the machine up enough to disable your brain, if it thinks you’re in pain , the alarm will go off again sooner or later, most likely shortly after the TENS is turned off.
Vance et al. believe that “TENS has been shown to provide analgesia specifically when applied at a strong, non-painful intensity.”
This particular study compared the effects of electrical muscle stimulation, massage and passive rest in athletes after 6 different bouts of exhausting supra maximal training. The chart on the left shows the peak power production following each of these modalities. The chart on the right shoes the blood lactate concentrations following the exercise bouts. As you can see, no significant differences were demonstrated between the effects of EMS, massage and passive rest on recovery markers or peak power output.
Even though there is controversy over the topic, some people can find symptom relief following TENS. If your goal is pain reduction, you can buy a TENS machine for less than $100 at your nearest pharmacy!
Pinar S., Kaya F., Bicer B., Erzeybek M.S., Cotuk H.B. DIFFERENT RECOVERY METHODS AND MUSCLE PERFORMANCE AFTER EXHAUSTING EXERCISE: COMPARISON OF THE EFFECTS OF ELECTRICAL MUSCLE STIMULATION AND MASSAGE
Martin N.A., Zoeller R.F., Robertson R.J. The comparative effects of sports massage, active recovery, and rest in promoting blood lactate clearance after supramaximal leg exercise. J. Athl. Train. 1998;33:30-35.