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To investigate the effects of high-intensity contractions and low-intensity contractions with and without blood flow restriction on changes in blood pressure and hemodynamic parameters. A total of 179 participants (18–35 years) were randomly assigned to one of three training groups that exercised 3 times per week for six weeks or a non-exercise control group. The groups are as follows: 1) Control [CON, n = 44]; 2) completed 4 sets of two-minute isometric contractions at 30% maximal voluntary contraction [LI, n = 47]; 3) completed 4 sets of two-minute isometric contractions at 30% maximal voluntary contraction with a 12 cm cuff inflated to 50% of arterial occlusion pressure [LI+BFR, n = 41]; or 4) completed 4 maximal isometric contractions lasting 5 seconds [MAX, n = 47]. Blood pressure, vascular resistance, and reactive hyperemia were measured at pre and post. Data are presented as means (SD). There was no evidence that SBP (BF10: 0.066), DBP (BF10: 0.057), vascular resistance (BF10: 0.085), or peak reactive hyperemia changed (BF10: 0.044) or A.U.C. (BF10: 0.074). Change scores for SBP were 1.1 (6.7), 0.7 (5.8), −0.4 (6.5), and −0.9 (6.3) mmHg for CON, LI, LI+BFR, and MAX, respectively. DBP change scores were 1.5 (6.6), 1.5 (7), −0.7 (5.9), and 0.3 (6.3) mmHg for CON, LI, LI+BFR, and MAX, respectively. Although recommended as a non-pharmacological method of blood pressure control, isometric exercise with or without BFR did not lower blood pressure. Future work could examine the inclusion of a daily strength test prior to the low intensity protocol. [ABSTRACT FROM AUTHOR]

It was previously hypothesized that the cross-education of strength is asymmetrical, where a greater transfer of strength is observed from the dominant to the non-dominant limb. The purpose of this study was to examine if the magnitude of cross-education of strength differed between dominant and non-dominant limbs following unilateral high-load resistance training. One hundred and twenty-two participants were randomized to one of the three groups: 1) training on the dominant arm (D-Only), 2) training on the non-dominant arm (ND-Only) and 3) a time-matched non-exercise control (Control). The training groups completed 6 weeks (18 sessions) of unilateral elbow flexion exercise. Each training session started with one-repetition maximum (1RM) training (≤ five attempts), followed by four sets of high-load exercise (i.e. 8–12RM). Strength changes of the untrained arm were compared between groups. Changes in the strength of the untrained arm were greater in D-Only (1.5 kg) and ND-Only (1.3 kg) compared to Control (−0.2 kg), without differences between D-Only and ND-Only. Unilateral resistance training increased strength in the opposite untrained arm, and the magnitude of this effect was similar regardless of which arm was trained. However, there is still considerable uncertainty on this topic and additional research is warranted to confirm the current findings. [ABSTRACT FROM AUTHOR]

Aberrant, neovascular retinal blood vessel growth is a vision-threatening complication in ischemic retinal diseases. It is driven by retinal hypoxia frequently caused by capillary nonperfusion and endothelial cell (EC) loss. We investigated the role of EC apoptosis in this process using a mouse model of ischemic retinopathy, in which vessel closure and EC apoptosis cause capillary regression and retinal ischemia followed by neovascularization. Protecting ECs from apoptosis in this model did not prevent capillary closure or retinal ischemia. Nonetheless, it prevented the clearance of ECs from closed capillaries, delaying vessel regression and allowing ECs to persist in clusters throughout the ischemic zone. In response to hypoxia, these preserved ECs underwent a vessel sprouting response and rapidly reassembled into a functional vascular network. This alleviated retinal hypoxia, preventing subsequent pathogenic neovascularization. Vessel reassembly was not limited by VEGFA neutralization, suggesting it was not dependent on the excess VEGFA produced by the ischemic retina. Neutralization of ANG2 did not prevent vessel reassembly, but did impair subsequent angiogenic expansion of the reassembled vessels. Blockade of EC apoptosis may promote ischemic tissue revascularization by preserving ECs within ischemic tissue that retain the capacity to reassemble a functional network and rapidly restore blood supply., Introduction Angiogenesis is the growth of new blood vessels from preexisting vessels and occurs through a tightly regulated response of endothelial cells (ECs) to proangiogenic factors (1, 2). Insufficient vascular [...]

: Introduction: Sarcopenia is an important clinical syndrome in older people living with HIV (PLWH). With a change to the Asia sarcopenia definition in 2019, we aimed to determine whether health outcomes were associated with different definitions of sarcopenia among Asian PLWH. Methods: We performed a prospective cross‐sectional study enrolling PLWH aged ≥35 years from January 2018 to November 2021. We defined sarcopenia by the Asia Working Group of Sarcopenia (AWGS) criteria in 2014 and 2019. AWGS‐2014 included low muscle mass plus weak handgrip strength and/or slow gait speed. AWGS‐2019 included low muscle mass plus low muscle strength or physical performance, while the presence of all defines severe sarcopenia. We measured appendicular skeletal muscle mass using dual‐energy X‐ray absorptiometry, handgrip strength, usual gait speed, five‐time chair stand test and Short Physical Performance Battery. Correlations between each sarcopenia definition and health‐related quality of life (using EQ‐5D‐5L and SF‐36) and functional disability were determined. Results: One hundred and fifty Asian PLWH were enrolled, 132 (88%) were male, mean age was 60±10 years, duration of HIV diagnosis was 13 (IQR 8–18) years and current CD4 count was 574 (IQR 362–762) cells/mm[sup.3], 67 (45%) had multimorbidity, 64 (43%) had polypharmacy. Prevalence of sarcopenia by AWGS‐2014, AWGS‐2019 and severe sarcopenia was 17.3%, 27.3% and 18.0%, respectively. Age, education and polypharmacy were associated with sarcopenia. Sarcopenia (AWGS‐2014) and severe sarcopenia were associated with mobility, physical functioning and physical component score (SF‐36). All three criteria were associated with impaired instrumental activities of daily living (IADL). After age and sex adjustment, sarcopenia (AWGS‐2014) (adjusted odds ratio/aOR 5.4, 95% confidence interval/CI 2.0–15.1) and severe sarcopenia (aOR 5.1, 95% CI 1.9–14.0) were associated with mobility and physical component score (SF‐36) (β coefficients –5.3342, p = 0.022 and –5.412, p = 0.019). Sarcopenia (AWGS 2014) (aOR 5.2, 95% CI 1.7–16.2), sarcopenia (AWGS‐2019) (aOR 4.5, 95% CI 1.5–13.1) and severe sarcopenia (aOR 3.5, 95% CI 1.1–10.9) were associated with impaired IADL in fully adjusted models. Conclusions: In a sample of Asian PLWH, 17.3%, 27.3% and 18.0% had sarcopenia as defined by AWGS‐2014, AWGS‐2019 and severe sarcopenia, respectively. Sarcopenia by AWGS‐2014 and severe sarcopenia correlated with parameters of poor health outcomes, while sarcopenia by AWGS‐2019 correlated with functional disability., INTRODUCTION Sarcopenia, deriving from the Greek words sarx (meaning “flesh”) and penia (meaning “loss”), was proposed by Irwin Rosenberg in 1988 to describe an age‐related loss of muscle mass and [...]

To determine (a) the impact of ischemic preconditioning pressures (applied as a % of arterial occlusion pressure [AOP]) on pressure pain threshold (PPT) and resistance exercise performance and (b) whether changes in performance could be explained by changes in PPT. Subjects (n539) completed 4 protocols in a randomized order: (a) ischemic preconditioning (IPC) at 110% AOP (IPC 110%), (b) IPC at 150% AOP (IPC 150%), (c) IPC at 10% AOP (Sham), and (d) time-matched control (CON). Each protocol included 4 cycles of 5 minutes of occlusion followed by 5 minutes of reperfusion. Pressure pain threshold was taken before and after. Discomfort ratings were given at the end of each cycle. Every visit finished with 2 sets of 75-second maximal isokinetic unilateral elbow flexion or extension. Overall, IPC 110% and IPC 150% resulted in similar increases in PPT relative to CON [110%: difference of 0.36 (0.18, 0.54) kg·m-2; 150%: difference of 0.377 (0.15, 0.59) kg·m-2] and Sham. Both resulted in greater discomfort than Sham and CON, with IPC 150% inducing greater discomfort than IPC 110% (BF10: 14.74). There were no differences between the conditions for total work (BF10: 0.23), peak torque (BF10: 0.035), or average power (BF10: 0.159). We did not find evidence that PPT mediated performance. We did not detect changes in performance with 2 different relative pressures greater than AOP. Our mean applied pressures were lower than those used previously. There might be a minimal level of pressure (e.g., >150% of AOP) that is required to induce ergogenic effects of ischemic preconditioning. [ABSTRACT FROM AUTHOR]