Technological clothing, such as compression garments (CG), has been increasingly used by athletes for training and racing. Compression socks (CS) in particular have been anecdotally reported to decrease the perception of calf strain felt while exercising. Previous studies have demonstrated a positive influence on peripheral circulatory measures and exercise duration with the use of CG; however, these results were obtained using treadmills and were not correlated with overall performance. The investigators sought to examine the impact of CS on both physiological responses and performance indicators after prolonged trail running in experienced off-road runners. The results did not demonstrate any practical or physiological benefits with the use of CS.
Eleven trained male runners participated in both laboratory and field sessions. The laboratory session involved an incremental exercise test to exhaustion on a treadmill to determine maximal oxygen uptake, maximal ventilation, and maximal heart rate. The field sessions required the completion of two 15.6-km trail runs at maximal effort, one wearing CS and one without. Each trail run was divided into three 5.2-km loops with a 40-second rest period in between to allow for data acquisition. During the rest period, ratings of perceived exertion (overall, heart/lungs, and legs) were obtained as was a blood sample for blood lactate concentration. Before and after the run sessions, measurements of maximal voluntary contraction and countermovement jump were obtained. The muscular oxygen uptake and blood flow were also calculated using near-infrared spectroscopy measurements (NIRS) from a probe attached to the vastus lateralis muscle.
There was a significantly higher value in muscle oxygenation and blood flow between the pre- and post-group for both CS and non-CS runs, which may be an expected finding after any exercise. No significant difference in run times, blood lactate concentrations, heart rate, NIRS parameters, or ratings of perceived exertion was found between the non-CS and CS runs. These data suggest that there are no true physiological or performance benefits from wearing CS under these conditions. Limitations of this study include the small number of participants, the lack of female participants, and the short duration of the race.
(Eur J Sport Sci. 2014;14:144–150) F Vercruyssen, C Easthope, T Bernard, et al.
Prepared by Pearlly Ng, MD, University of Utah Wilderness Medicine Fellow, Salt Lake City, UT, USA.