Effects of lymphatic drainage and cryotherapy on indirect markers of muscle damage.

BACKGROUND: Muscle enzymes are cleared from the extracellular space by the lymphatic system, while smaller proteins enter the bloodstream directly. We investigated if manual lymphatic drainage (MLD), local cryotherapy (CRY), and rest (RST) differently affect the time course of creatine kinase (CK, 84 kDa) and heart-type fatty acid binding protein (h-FABP, 15 kDa) in the blood.

METHODS: Randomized controlled trial. After 4x20 unilateral, eccentric accentuated knee extensions (with one-third of the maximal isometric force) 30 sports students randomly received either a 30 min MLD, CRY or they rested (RST) for the same amount of time. CK, h-FABP, neutrophil granulocytes, and the perceived muscle soreness were assessed before, immediately after, and 1 hour, 4 hours, and 24 hours after the exercise.

RESULTS: All measures increased significantly (P<0.001) after the protocol indicating that muscle damage was induced. However, the responses did not differ between the treatments.

CONCLUSIONS: Large and small damage markers were not affected differently by MLD, CRY, or RST, when applied for 30 min and no beneficial effects on inflammation or muscle soreness could be found for MLD and CRY when compared to RST. This information is particularly important for those sports physicians and conditioning specialists who use biochemical muscle damage markers to adjust the training load and volume of athletes.