Part 3: Acupuncture, Ultrasound, Electrical Stimulation, Laser Therapy and Hyperbaric Oxygen
Acupuncture is a treatment modality in which thin needles are inserted into the body for therapeutic purposes. It originates from China more than 2,500 years ago and remains a key component of traditional Chinese medicine to treat a wide variety of ailments. In western cultures, it falls under the category of complementary and alternative medicine. Studies have linked acupuncture to reduced cardiovascular disease and hypertension, among other chronic diseases (WHO, 2003). In athletes, acupuncture has been reported to help with exercise performance and recovery. Acupuncture is generally considered to be safe when performed by a trained practitioner using clean and single use needles. Although traditionally it involves only needles, some practitioners may apply a small electric current, a modality termed ‘electroacupuncture.’ Acupuncture should not be confused with dry needling. Dry needling is used by physical therapist with a very different training background to treat musculoskeletal trigger points.
Ultrasound has been promoted as a potential treatment modality for muscle injury, for both pain relief and muscle regeneration (Delos, 2013). Despite its widespread use, including by more than 80% of physical therapists, there are no clear indicators that it enhances recovery from activity or injury. The scientific explanation of how ultrasound provides healing benefits is unclear. Early research showed that ultrasound promotes satellite cell proliferation, but the clinical significance of that was unclear (Rantanen, 1999). In individuals with skeletal muscle injuries, adding ultrasound to exercise did not improve recovery compared to exercise alone (Markert, 2005).
Neuromuscular electrical stimulation (NMES) involves using low stimulation frequencies which induce contractions comparable to active recovery. Researchers have postulated that this may favor increased blood flow to muscles, improved oxygenation and metabolite wash out following exercise. Submotor stimulation may also have an analgesic effect on muscle soreness. Theoretically, this may reduce microvascular permeability, minimizing protein leakage and also repelling large, negatively charged proteins from the interstitial space. Notably, the evidence supports the use of NMES in recovery from surgery (i.e. quad recovery after ACL or knee replacement) or in stroke patients, thus providing a strong theoretical bases for use in athletes.
Low level laser therapy (LLLT) has been used in the treatment of musculoskeletal pain. There have been some positive findings in the treatment of fibromyalgia and cervicalgia. Light-emitting diode therapy (LEDT) is another modality used to treat musculoskeletal injuries. These modalities appear to induce a photochemical effect in cells through absorption of light by photoreceptors, often described as “photobiostimulation” or “photobiomodulation” (Leal-Junior, 2015). The magnitude of the effect is influenced by wavelength, energy density (or fluence), power density, type of injury, and the absorption spectrum of photoreceptor.
Hyperbaric oxygen therapy (HBOT) is administration of therapeutic oxygen, usually at 100% FiO2 at greater than environmental or atmospheric pressure. Typically, you place the patient in an airtight compartment, increase the pressure and administer oxygen. For therapeutic purposes, this is typically done between 60-120 minutes at a time. HBOT is used in medicine for treating illnesses such as decompression sickness, carbon monoxide poisoning and diabetic ulcers. It has been suggested in the literature that HBOT can be used to treat muscle contusions and sports-related injuries (Tiidus, 2015).
Acupuncture as a recovery modality suffers from a lack of studies investigating its utility. Although it cannot be recommended for recovery, it is generally considered safe in the hands of a trained acupuncturist. There are a multitude of studies investigating both ultrasound and neuromuscular electrical stimulation as recovery modalities with the vast majority finding no benefit in the recovering athlete. These can not be endorsed with confidence. Low level laser therapy has compelling data to support its utility as a recovery modality when utilized prior to exercise. It may even be superior to cryotherapy. Hyperbaric oxygen therapy does not demonstrate any benefit to the recovering athlete, and due to the risks associated with hyperbaric chamber and hyperoxia, it should be avoided.