The Effect of Low Intensity Wearable Ultrasound on Blood Lactate and Muscle Performance after High Intensity Resistance Exercise

Langer MD, Byrne HK, Henry T, Lewis G, Mattern C. The Effect of Low Intensity Wearable Ultrasound on Blood Lactate and Muscle Performance after High Intensity Resistance Exercise. JEPonline 2017;20(4):132-146. The purpose of this study was to determine if a low intensity wearable ultrasound (LIWU) device enhances recovery from exercise by reducing blood lactate resulting in improved isokinetic muscle performance after lower extremity resistance exercise. The impact of LIWU on exercise recovery and performance were explored through, a double-blind, sham-controlled, crossover design. Sixteen subjects completed 1-repitition maximum (1-RM) estimation for five lower-body resistance exercises. The subjects performed identical exercise sessions wearing either an active LIWU or a sham device applied to the quadriceps and hamstrings at rest and during exercise. Blood lactate concentration was measured before circuit weight training at 70% of the 1-RM and during the 60min recovery. After recovery, the subjects performed leg extension and flexion exercises on an isokinetic dynamometer at two movement speeds. At each post-exercise time point, the lactate concentration was significantly reduced in the active treatment compared to the sham treatment. There were also significant differences between the active and sham conditions on muscle performance. These data suggest the LIWU device is an effective modality for reducing post-exercise blood lactate and improving slow speed knee extension.