The Effect of Reducing Soreness in Marathon Runners

The Effect of Pulsed Electromagnetic Field Therapy in Reducing Delayed Onset Muscle Soreness in Marathon Runners. A Double-blind Randomized Placebo-controlled Study.

Delayed onset muscle soreness is defined as the sensition of pain and discomfort in skeletal muscles that occurs after eccentric muscle actions or strenuous exercise like a marathon.

There is a growing body of clinical evidence which shows that noninvasive, nonpharmacologic pulsed electromagnetic fields have many clinical effects. Pulsed electromagnetic fields have shown to reduce pain in different groups of patients. This concerns patients with osteoarthritis, rheumatoid arthritis, diabetic neuropathy, fibromyalgia, distal radius fractures, pelvic pain and postoperative patients. A marathon is a muscular strain. Physiologic effects of a marathon involves muscular and connective tissue damage which initiates an inflammatory response as well as release of metabolic factors like lactate and free radicals, intracellular metabolites and by-products of proteolysis. The objective of this study was to investigate the efficacy of pulsed electromagnetic fields compared to placebo in reducing delayed onset muscle soreness in marathon runners.

Every person received two active devices. The devices emitted 2-ms bursts of 27.12 MHz sinusoidal waves repeating at 2 bursts/s. Peak magnetic field intensity was 0.05 G which induced an average electric field of 10 mV in the tissue with an effect of 7.3 mW/cm3.

Primary outcome of thigh pain during semi-squat during 5 days following the marathon showed a significantly lower pain among the active group compared to the placebo group. The outcome was thigh muscle pain measured on a 10 cm visual analog scale during a squat of 90 degrees three times a day; when they woke up, at 12 pm and 8 pm.

The group that received active pulsed electromagnetic field was running for a significant longer time the first day following the marathon.

Inclusion Criteria: Completion of a marathon Age > 18 years Exclusion Criteria: - Unable to read and speak Danish