Sequential Pulse Compression’s Effect on Blood Flow in the Lower-Extremity

2020 ◽  
Vol 29 (1) ◽  
pp. 7-11 ◽  
Author(s):  
Kelly A. Brock ◽  
Lindsey E. Eberman ◽  
Richard H. Laird ◽  
David J. Elmer ◽  
Kenneth E. Games

Context: Several interventions are available to reduce the intensity and duration of the unwanted effects (eg, muscle soreness) associated with physical activity, such as massage, compression garments, and sequential pulse compression (SPC). Such interventions aim to increase blood flow to alleviate symptoms. However, there is a lack of evidence to support the use of SPC to alter total hemoglobin concentration (THb) in active individuals. Objective: To examine the acute effects of a single session of SPC on hemoglobin concentration compared with a control condition. Design: Single cohort, crossover design. Participants: Thirty-four physically active and healthy participants (females = 12 and males = 22) completed the study. Interventions: The authors randomly assigned participants to first receive the experimental (SPC) or control condition. Measures were recorded precondition and postcondition. Participants returned to the laboratory to complete the second condition ≥24 hours after the first condition. Main Outcome Measures: Relative changes in THb, deoxygenated hemoglobin, and oxygenated hemoglobin measures were recorded using near-infrared spectroscopy placed on the muscle belly of the medial gastrocnemius of the dominant limb. Results: SPC significantly increased THb (P < .001, d = 0.505) and oxygenated hemoglobin (P < .001, d = 0.745) change scores compared with the control condition. No statistical difference in deoxygenated hemoglobin change scores was found between the SPC and control conditions, but a medium effect size suggests potential biological significance (P = .06, d = 0.339). Conclusions: Overall, SPC increases THb to the lower-extremity and may be a viable option in the management of muscle soreness related to physical activity.

Angiology ◽  
2001 ◽  
Vol 52 (7) ◽  
pp. 437-445 ◽  
Author(s):  
Lilja Petra Ásgeirsdóttir ◽  
Uggi Agnarsson ◽  
Guomundur S. Jónsson

Author(s):  
Tom Martinsson Ngouali ◽  
Mats Börjesson ◽  
Åsa Cider ◽  
Stefan Lundqvist

Swedish physical activity on prescription (PAP) is an evidence-based method to promote physical activity. However, few studies have investigated the effect of Swedish PAP on physical fitness, in which better cardiorespiratory fitness is associated with lower risks of all-cause mortality and diagnose-specific mortality. Direct measures of cardiorespiratory fitness, usually expressed as maximal oxygen uptake, are difficult to obtain. Hence, exercise capacity can be assessed from a submaximal cycle ergometer test, taking the linear relationship between heart rate, work rate, and oxygen uptake into account. The aim of this study was to evaluate exercise capacity in the long term, following PAP treatment with enhanced physiotherapist support in a nonresponding patient cohort. In total, 98 patients (48 women) with insufficient physical activity levels, with at least one component of the metabolic syndrome and nonresponding to a previous six-month PAP treatment, were randomized to PAP treatment with enhanced support from a physiotherapist and additional exercise capacity tests during a two-year period. A significant increase in exercise capacity was observed for the whole cohort at two-year follow-up (7.6 W, p ≤ 0.001), with a medium effect size (r = 0.34). Females (7.3 W, p = 0.025), males (8.0 W, p = 0.018) and patients ≥58 years old (7.7 W, p = 0.002) improved significantly, whereas a nonsignificant increase was observed for patients <58 years old (7.6 W, p = 0.085). Patients with insufficient physical activity levels who did not respond to a previous six-month PAP treatment can improve their exercise capacity following PAP treatment with enhanced support from a physiotherapist during a two-year period. Future studies should include larger cohorts with a control group to ensure valid estimations of exercise capacity and PAP.


1990 ◽  
Vol 69 (3) ◽  
pp. 830-836 ◽  
Author(s):  
M. C. Hogan ◽  
D. E. Bebout ◽  
A. T. Gray ◽  
P. D. Wagner ◽  
J. B. West ◽  
...  

In the present study we investigated the effects of carboxyhemoglobinemia (HbCO) on muscle maximal O2 uptake (VO2max) during hypoxia. O2 uptake (VO2) was measured in isolated in situ canine gastrocnemius (n = 12) working maximally (isometric twitch contractions at 5 Hz for 3 min). The muscles were pump perfused at identical blood flow, arterial PO2 (PaO2) and total hemoglobin concentration [( Hb]) with blood containing either 1% (control) or 30% HbCO. In both conditions PaO2 was set at 30 Torr, which produced the same arterial O2 contents, and muscle blood flow was set at 120 ml.100 g-1.min-1, so that O2 delivery in both conditions was the same. To minimize CO diffusion into the tissues, perfusion with HbCO-containing blood was limited to the time of the contraction period. VO2max was 8.8 +/- 0.6 (SE) ml.min-1.100 g-1 (n = 12) with hypoxemia alone and was reduced by 26% to 6.5 +/- 0.4 ml.min-1.100 g-1 when HbCO was present (n = 12; P less than 0.01). In both cases, mean muscle effluent venous PO2 (PVO2) was the same (16 +/- 1 Torr). Because PaO2 and PVO2 were the same for both conditions, the mean capillary PO2 (estimate of mean O2 driving pressure) was probably not much different for the two conditions, even though the O2 dissociation curve was shifted to the left by HbCO. Consequently the blood-to-mitochondria O2 diffusive conductance was likely reduced by HbCO.(ABSTRACT TRUNCATED AT 250 WORDS)


Biomechanics ◽  
2021 ◽  
Vol 1 (2) ◽  
pp. 202-213
Author(s):  
Harish Chander ◽  
Sachini N. K. Kodithuwakku Arachchige ◽  
Alana J. Turner ◽  
Reuben F. Burch V ◽  
Adam C. Knight ◽  
...  

Background: Occupational footwear and a prolonged duration of walking have been previously reported to play a role in maintaining postural stability. The purpose of this paper was to analyze the impact of three types of occupational footwear: the steel-toed work boot (ST), the tactical work boot (TB), and the low-top work shoe (LT) on previously unreported lower extremity muscle activity during postural stability tasks. Methods: Electromyography (EMG) muscle activity was measured from four lower extremity muscles (vastus medialis (VM), medial hamstrings (MH), tibialis anterior (TA), and medial gastrocnemius (MG) during maximal voluntary isometric contractions (MVIC) and during a sensory organization test (SOT) every 30 min over a 4 h simulated workload while wearing ST, TB, and LT footwear. The mean MVIC and the mean and percentage MVIC during each SOT condition from each muscle was analyzed individually using a repeated measures ANOVA at an alpha level of 0.05. Results: Significant differences (p < 0.05) were found for maximal exertions, but this was limited to only the time main effect. No significant differences existed for EMG measures during the SOT. Conclusion: The findings suggest that occupational footwear type does not influence lower extremity muscle activity during both MVIC and SOT. Significantly lower muscle activity during maximal exertions over the course of the 4 h workload was evident, which can be attributed to localized muscular fatigue, but this was not sufficient to impact muscle activity during postural stability tasks.


Circulation ◽  
2021 ◽  
Vol 143 (Suppl_1) ◽  
Author(s):  
Megan C Nelson ◽  
Madeline P Casanova ◽  
Jennavere R Ball ◽  
Rachel D Midence ◽  
Timothy R Johnson ◽  
...  

Introduction: A single bout of uninterrupted sitting impairs vascular function in the legs, which may be due to reductions in blood flow and shear stress. Participating in regular moderate-to-vigorous physical activity (MVPA) has been identified as an effective approach for improving vascular function, and recent evidence suggests meeting the physical activity (PA) guidelines may attenuate some of the negative health outcomes associated with excessive sedentary behavior; however, it is not well understood how meeting the PA guidelines may influence the acute response to sitting. Our aim was to investigate the effects of 3 h of uninterrupted sitting on hemodynamics and vascular and inflammatory biomarkers in physically inactive and active adults. Hypothesis: We hypothesized active adults would experience less detrimental physiological changes after sitting compared to inactive adults. Methods: Eleven inactive (mean±SD, age: 47.1±8.9 y, body fat: 33.1±8.5%; 78.5% women) and 16 active adults (age: 46.1±8.9 y, body fat: 25.2±7.2%; 31.1% women) completed 3 h of uninterrupted sitting. Adults self-reported their PA with the International PA Questionnaire. Adults engaging in ≥150 min·wk -1 were classified as active and <150 min·wk -1 , inactive. Hemodynamic variables, and superficial femoral artery (SFA) diameter and blood velocity were measured each hour over 3 h of sitting. Mean arterial pressure, blood flow and shear rate were calculated. Serum vascular and inflammatory biomarkers were measured pre and post sitting. Linear mixed-effects modeling was used to assess changes in dependent variables over time and between inactive and active adults, controlling for sex. Results: Inactive and active adults self-reported 7.3±7.1 and 93.3±64.8 min·d -1 of MVPA, respectively. Endothelin-1 (baseline: 8.3±13.4 pg/mL, post: 81.1±103.0 pg/mL; p<0.001) and interleukin-6 (baseline: 0.08±0.06 pg/mL, post: 0.11±0.11 pg/mL; p=0.03) increased post sitting compared to baseline in all adults, regardless of PA status. Systolic blood pressure, mean arterial pressure, calf circumference, and SFA diameter, blood velocity, and mean blood flow decreased over time in both groups (p<0.05 for all). There was an interaction effect for mean shear rate (p=0.008); inactive adults experienced a decline over 3 h of sitting (baseline: 76.1±48.2 s -1 ; 1 h: 55.0±27.4 s -1 ; 2 h: 45.3±24.2 s -1 ; 3 h: 40.8±25.5 s -1 ) while active participants demonstrated no change (baseline: 36.6±21.4 s -1 ; 1 h: 28.1±21.4 s -1 ; 2 h: 26.1±20.9 s -1 ; 3 h: 23.8±19.5 s -1 ). Inactive adults also had a higher oscillatory shear index compared to active adults (p<0.001). Conclusion: Uninterrupted sitting induced unfavorable changes regardless of PA status; however, active adults demonstrated a more favorable shear profile. Meeting PA guidelines may attenuate some unfavorable changes within the vasculature associated with prolonged sitting.


1988 ◽  
Vol 65 (6) ◽  
pp. 2592-2597 ◽  
Author(s):  
P. R. Bender ◽  
B. M. Groves ◽  
R. E. McCullough ◽  
R. G. McCullough ◽  
S. Y. Huang ◽  
...  

Residence at high altitude could be accompanied by adaptations that alter the mechanisms of O2 delivery to exercising muscle. Seven sea level resident males, aged 22 +/- 1 yr, performed moderate to near-maximal steady-state cycle exercise at sea level in normoxia [inspired PO2 (PIO2) 150 Torr] and acute hypobaric hypoxia (barometric pressure, 445 Torr; PIO2, 83 Torr), and after 18 days' residence on Pikes Peak (4,300 m) while breathing ambient air (PIO2, 86 Torr) and air similar to that at sea level (35% O2, PIO2, 144 Torr). In both hypoxia and normoxia, after acclimatization the femoral arterial-iliac venous O2 content difference, hemoglobin concentration, and arterial O2 content, were higher than before acclimatization, but the venous PO2 (PVO2) was unchanged. Thermodilution leg blood flow was lower but calculated arterial O2 delivery and leg VO2 similar in hypoxia after vs. before acclimatization. Mean arterial pressure (MAP) and total peripheral resistance in hypoxia were greater after, than before, acclimatization. We concluded that acclimatization did not increase O2 delivery but rather maintained delivery via increased arterial oxygenation and decreased leg blood flow. The maintenance of PVO2 and the higher MAP after acclimatization suggested matching of O2 delivery to tissue O2 demands, with vasoconstriction possibly contributing to the decreased flow.


2006 ◽  
Vol 100 (3) ◽  
pp. 850-857 ◽  
Author(s):  
Kenneth M. Tichauer ◽  
Derek W. Brown ◽  
Jennifer Hadway ◽  
Ting-Yim Lee ◽  
Keith St. Lawrence

Impaired oxidative metabolism following hypoxia-ischemia (HI) is believed to be an early indicator of delayed brain injury. The cerebral metabolic rate of oxygen (CMRO2) can be measured by combining near-infrared spectroscopy (NIRS) measurements of cerebral blood flow (CBF) and cerebral deoxy-hemoglobin concentration. The ability of NIRS to measure changes in CMRO2 following HI was investigated in newborn piglets. Nine piglets were subjected to 30 min of HI by occluding both carotid arteries and reducing the fraction of inspired oxygen to 8%. An additional nine piglets served as sham-operated controls. Measurements of CBF, oxygen extraction fraction (OEF), and CMRO2 were obtained at baseline and at 6 h after the HI insult. Of the three parameters, only CMRO2 showed a persistent and significant change after HI. Five minutes after reoxygenation, there was a 28 ± 12% (mean ± SE) decrease in CMRO2, a 72 ± 50% increase in CBF, and a 56 ± 19% decrease in OEF compared with baseline ( P < 0.05). By 30 min postinsult and for the remainder of the study, there were no significant differences in CBF and OEF between control and insult groups, whereas CMRO2 remained depressed throughout the 6-h postinsult period. This study demonstrates that NIRS can measure decreases in CMRO2 caused by HI. The results highlight the potential for NIRS to be used in the neonatal intensive care unit to detect delayed brain damage.


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