Efficacy of Downhill Running to Prepare for Mountain Hiking with Pack Weight.

Unaccustomed eccentric exercise can result in severe muscle soreness MS, strength loss, and muscle damage. However, personnel may be able to prepare the muscles in advance by performing a similar but less time consuming eccentric activity. This study determined if downhill running could reduce adverse symptoms that may be associated with a subsequent novel mountain hiking exercise. Special operation volunteers were assigned to either a treatment group DHR or a control group CRL. DHR performed two 3 mile downhill runs, while CRL followed their normal training schedule. Two weeks after the second downhill run, both groups completed two 6 mile mountain hikes while carrying 30 of their body weight. MS, isometric leg endurance, and plasma creatine kinase CK were measured before and after the downhill runs and the hikes. Subjects in DHR exhibited neither significantly greater reductions in MS, CK, or in strength loss after either hike, nor a significant improvement in hiking performance compared to CRL. Therefore, downhill running does not appear to provide significant protection against MS, muscle damage CK, or short term strength losses that accompany unaccustomed mountain hiking.