Sands, McNeal, Murray & Stone (2015) Dynamic Compression Enhances Pressure-to-Pain Threshold in Elite Athlete Recovery: Exploratory Study.
Athlete recovery-adaptation is crucial to the progress and performance of highly trained athletes. The purpose of this study was to assess peristaltic pulse dynamic compression (PPDC) in reducing short-term pressure-to-pain threshold (PPT) among Olympic Training Center athletes after morning training. Muscular tenderness and stiffness are common symptoms of fatigue and exercise-induced muscle microtrauma and edema. Twenty-four highly trained athletes (men = 12 and women = 12) volunteered to participate in this study. The athletes were randomly assigned to experimental (n = 12) and control (n = 12) groups. Pressure-to-pain threshold measurements were conducted with a manual algometer on 3 lower extremity muscles. Experimental group athletes underwent PPDC on both legs through computer-controlled circumferential inflated leggings that used a peristaltic-like pressure pattern from feet to groin. Pressures in each cell were set to factory defaults. Treatment time was 15 minutes. The control group performed the same procedures except that the inflation pump to the leggings was off. The experimental timeline included a morning training session, followed by a PPT pretest, treatment application (PPDC or control), an immediate post-test (PPT), and a delayed post-test (PPT) after the afternoon practice session. Difference score results showed that the experimental group's PPT threshold improved after PPDC treatment immediately and persisted the remainder of the day after afternoon practice. The control group showed no statistical change. We conclude that PPDC is a promising means of accelerating and enhancing recovery after the normal aggressive training that occurs in Olympic and aspiring Olympic athletes.
Kephart, Mobley, Fox, Pascoe, Sefton, Wilson, Goodlett, Kavazis, Roberts & Martin (2015) A single bout of whole-leg, peristaltic pulse external pneumatic compression upregulates PGC-1α mRNA and endothelial nitric oxide sythase protein in human skeletal muscle tissue.
What is the central question of this study? Does 60 min of peristaltic pulse external pneumatic compression (EPC) alter gene and protein expression patterns related to metabolism, vascular biology, redox balance and inflammation in vastus lateralis biopsy samples? What is the main finding and its importance? A single bout of EPC transiently upregulates PGC-1α mRNA, while also upregulating endothelial nitric oxide synthase protein and nitric oxide metabolite concentrations in vastus lateralis biopsy samples. We investigated whether a single 60 min bout of whole-leg, lower pressure external pneumatic compression (EPC) altered select vascular, metabolic, antioxidant and inflammation-related mRNAs. Ten participants (eight male, two female; aged 22.0 ± 0.4 years) reported to the laboratory 4 h postprandial, and vastus lateralis muscle biopsies were obtained before (PRE) and 1 and 4 h after EPC treatment. Messenger RNA expression was analysed using real-time RT-PCR, and significant mRNA findings were investigated further by Western blot analysis of respective protein concentrations. Peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) mRNA increased by 77% 1 h following EPC compared with PRE levels (P = 0.005), but no change in protein concentration 1 or 4 h post-EPC was observed. Increases in endothelial nitric oxide sythase (eNOS) mRNA (+44%) and superoxide dismutase 2 (SOD2) mRNA (+57%) 1 h post-EPC as well as an increase in interleukin-10 mRNA (+132%) 4 h post-EPC compared with PRE levels were observed, but only approached significance (P = 0.076, 0.077 and 0.074, respectively). Interestingly, eNOS protein (+40%, P = 0.025) and nitrate and nitrite (NOx) concentrations (+69%, P = 0.025) increased 1-4 h post-EPC. Moreover, SOD2 protein tended to increase from PRE to 4 h post-EPC (+43%, P = 0.074), although no changes in tissue 4-hydroxnonenal levels was observed. An acute bout of EPC transiently upregulates PGC-1α mRNA, while also upregulating eNOS protein and NOx concentrations in vastus lateralis biopsy samples. Future research should characterize the origin of these responses (e.g. vascular or muscle fibre cells) and how the acute effects of EPC application on gene and protein expression observed herein are associated with functional improvements (e.g. metabolism, vascular function) in acute and chronic models.
Sands, Murray, MB Murray, SR, McNeal, Mizuguchi, Sato & Stone (2014) Peristaltic pulse dynamic compression of the lower extremity enhances flexibility.
This study investigated the effects of peristaltic pulse dynamic compression (PPDC) on range-of-motion (ROM) changes in forward splits. Serious stretching usually involves discomfort and large time investments. Tissue structural changes and stretch tolerance have heretofore been considered the primary mechanisms of enhanced ROM. The PPDC treatment was computer controlled. Circumferential and segmented inflation pressures were induced by feet to hip leggings. Nine subjects, experienced in stretching and a forward split position, volunteered. The subjects were familiarized with the protocol and randomly assigned to an initial condition: experimental (PPDC), or control (CONT). The study involved a crossover design. Second conditions were tested within 1-5 days. All tests were 2 trials of right and left forward splits. Split flexibility was assessed by measuring the height of the anterior superior iliac spine of the rear leg from the floor. Pelvic posture was controlled by rear leg position. The PPDC treatment was 15 minutes of seated PPDC. The control condition was the same except that leggings were not inflated. Pressures of 5 cells in the leggings were set at factory defaults, 70 mm Hg sequentially. Difference score results indicated statistically significant (p ≤ 0.05) differences by condition and the condition by leg interaction. The rapid acute changes in ROM (PPDC: right 25.3%, left 33.3%; CONT: right 12.2%, left 1.0%) support the premise that changes in ROM were dependent on mechanisms other than tissue structural changes and/or stretch tolerance. PPDC provides a means of rapidly enhancing acute ROM requiring less discomfort and time.
Introduction External pneumatic compression (EPC) is being employed for a widening range of clinical and non-clinical populations. However, EPC devices vary markedly in treatment pressures, duty cycles and application sites, and the acute effects of whole limb, lower pressure EPC on peripheral vascular function have not been determined.
Purpose The purpose of this study was to determine the acute effects of a single bout of peristaltic pulse EPC on peripheral conduit and resistance artery function.
Methods Twenty (n = 20; males = 12 and females = 8) young and apparently healthy subjects (aged 26.1 ± 8.2 years) participated in this study. A sequential EPC device with five inflation zones arranged linearly and inflating distal to proximal along the lower limbs was employed with target inflation pressures of 70 mmHg for 1 h. Flow-mediated dilation (FMD) of the brachial and popliteal arteries was evaluated with ultrasound before and after EPC. Venous occlusion plethysmography was employed to evaluate limb blood flow at rest and during reactive hyperemia (RH) in the forearm (FBF) and calf (CBF) before and after EPC.
Results Peak RH CBF was increased by 9 % after EPC (P < 0.05), whereas peak RH FBF (-10 %) did not change significantly (P > 0.25). Normalized popliteal artery FMD post-EPC (2.24 ± 1.41) was significantly higher than pre-EPC (1.36 ± 0.67, P = 0.015) and post-sham (1.58 ± 0.86, P = 0.032) values. Similarly, normalized brachial artery FMD post-EPC (1.47 ± 0.32) was significantly higher than pre-EPC (1.11 ± 0.41, P = 0.004) and post-sham (0.99 ± 0.27, P = 0.026) values.
Conclusion Acutely, whole limb, lower pressure EPC improves conduit artery endothelial function systemically, but only improves RH blood flow locally (i.e., compressed limbs).