Walking net V ˙ O2 rises with advancing age in older women: where to go from here?

PURPOSE: Walking net V ˙ O2 tends to increase with advancing age; however, factors contributing to this relationship have not been widely described. The implications of such findings could inform targeted strategies to promote independent mobility in older adults. Herein, we evaluated the relationship between net V ˙ O2 and age at two submaximal workloads while exploring potential moderators of this relationship. METHODS: Secondary analyses were performed on 35 older (65 ± 3 years) women who completed a battery of physical assessments including fixed-speed, non-graded and graded (+ 2.5%) treadmill walking with indirect calorimetry to determine net V ˙ O2. Maximal oxygen uptake ( V ˙ O2max), knee extensor maximal isometric voluntary contraction (MVC), peak rate of torque development (RTD), and plantar flexor range-of-motion (PFROM) were also measured. RESULTS: Bivariate correlations showed non-graded (r = 0.403, p = 0.017) and graded (r = 0.413, p = 0.014) net V ˙ O2 were positively related to age. Notably, these relationships strengthened after adjusting for V ˙ O2max. Regression modeling showed age, RTD:MVC ratio (composite of muscle performance), and PFROM together explained 49% and 34% of the variance in non-graded and graded net V ˙ O2, respectively. Further analyses suggested knee extensor MVC moderates the relationship between non-graded net V ˙ O2 and age, accounting for 9% of the variance [ΔR2 = 0.090, F (1,31) = 4.13, p = 0.05]. CONCLUSION: These data support the premise that, in older women, walking net V ˙ O2 rises with advancing age, and additionally, the RTD:MVC ratio and PFROM are independent correlates of non-graded net V ˙ O2. Exercise interventions with a high degree of training specificity including explosive, velocity-based elements may promote independent mobility in older women.

Serum syndecan-4 correlates with blood pressure and cardiovascular parameters but not proinflammatory markers in healthy older women.

Aging is accompanied by a low-grade proinflammatory status that plays a role in age-related vascular alterations. Syndecan-4 (SDC4) is a key component of the endothelial glycocalyx, and its extracellular domain can be shed by matrix metalloproteinase-9 (MMP-9). In vitro studies demonstrated that MMP-9-mediated shedding of SDC4 is induced by tumor necrosis factor-α (TNF- α) in human endothelial cells. However, the relationship between circulating shed SDC4, systemic inflammation, and age-related vascular alterations remains unknown. Here, we used linear regression models to examine the associations of serum SDC4 levels with cardiovascular hemodynamic phenotypes, serum MMP-9, and serum TNF-α and inteleukin-6 in healthy older women (n = 74). Serum SDC4 was not associated with proinflammatory cytokines or arterial elasticity. Nevertheless, we found significant correlations of SDC4 with MMP-9, heart rate, left ventricular ejection time, systemic vascular resistance, and blood pressure. Our preliminary evidence suggests that systemic inflammation might not induce SDC4 shedding in healthy aging.

Respiration mask waveguide optimisation for maximised speech intelligibility.

Both the scarcity and environmental impact of disposable face masks, as in the COVID-19 pandemic, have instigated the recent development of reusable masks. Such face masks reduce transmission of infectious agents and particulates, but often impact a user's ability to be understood when materials, such as silicone or hard polymers, are used. In this work, we present a numerical optimisation approach to optimise waveguide topology, where a waveguide is used to transmit and direct sound from the interior of the mask volume to the outside air. This approach allows acoustic energy to be maximised according to specific frequency bands, including those most relevant to human speech. We employ this method to convert a resuscitator mask, made of silicone, into respiration personal protective equipment (PPE) that maximises the speech intelligibility index (SII). We validate this approach experimentally as well, showing improved SII when using the fabricated device. Together, this design represents a unique and effective approach to utilize and adapt available apparatus to filter air while improving the ability to communicate effectively, including in healthcare settings.

Divergent Blood Pressure Response After High-Intensity Interval Exercise: A Signal of Delayed Recovery?

Hunter, GR, Fisher, G, Bryan, DR, Borges, JH, and Carter, SJ. Divergent blood pressure response after high-intensity interval exercise: a signal of delayed recovery? J Strength Cond Res 32(11): 3004-3010, 2018-The objective of this commentary is to highlight potential factors influential to the adaptation of high-intensity exercise. Herein, we present a rationale supporting the contention that elevated systolic blood pressure, after a bout of high-intensity exercise, may be indicative of delayed/incomplete recovery. Relative to type I skeletal muscle fibers, the unique cellular/vascular characteristics of type II muscle fibers may necessitate longer recovery periods, especially when exposed to repeated high-intensity efforts (i.e., intervals). In addition to the noted race disparities in cardiometabolic disease risk, including higher mean blood pressures, African Americans may have a larger percentage of type II muscle fibers, thus possibly contributing to noted differences in recovery after high-intensity exercise. Given that optimal recovery is needed to maximize physiological adaptation, high-intensity training programs should be individually-tailored and consistent with recovery profile(s). In most instances, even among those susceptible, the risk to nonfunctional overreaching can be largely mitigated if sufficient recovery is integrated into training paradigms.

Implementation of a novel real-time platelet inventory management system at a multi-site transfusion service.

BACKGROUND: Blood platelets (PLTs) are a valuable commodity. Management of their inventory has implications both for patient care and for the cost of health care delivery. There are a variety of different methods of managing PLT inventory currently in practice and multiple theoretical models aimed at improving PLT inventory metrics. In this study we evaluate the ability of a novel electronic dashboard system that monitors and displays both PLT inventory and patient data to improve transfusion metrics at a quaternary health care center. STUDY DESIGN AND METHODS: The Capital District Health Authority is a quaternary health care center that transfuses approximately 2500 PLT units annually. To improve PLT discard rates a novel, low-overhead system that interfaces with the laboratory information system and displays real-time data between transfusion sites on PLT inventory and orders was implemented in November 2011. This study examines the transfusion quality metrics data from the 24 months before and after implementation. RESULTS: A significant reduction in mean monthly PLT outdate rate was observed after the implementation of the PLT dashboard suite from 24.5% (n = 24, SD ± 6.4%) to 15.1% (n = 24, SD ± 6.4%; p < 0.001). PLT age at time of transfusion was also reduced from 3.60 days (n = 4796, SD ± 0.97 days) to 3.46 days (n = 4881, SD ± 1.00 days; p < 0.001). CONCLUSIONS: This study describes the implementation of a novel PLT dashboard suite. This suite significantly reduced PLT outdate rates at our institution over the 48-month study period.

Frequency of combined resistance and aerobic training in older women.

The aim of this study was to determine the optimal frequency of combined aerobic and resistance training for improving muscular strength (MS), cardiovascular fitness (CF), and functional tasks (FTs) in women older than 60 years. Sixty-three women were randomly assigned to 1 of 3 exercise training groups. Group 1 performed 1 resistance exercise training (RET) and 1 aerobic exercise training (AET) session per week (AET/RET 1 × wk); group 2 performed 2 RET and 2 AET sessions per week (AET/RET 2 × wk); and group 3 performed 3 RET and 3 AET sessions per week (AET/RET 3 × wk). MS, CF, and FT measurements were made pretraining and 16 weeks posttraining. Repeated-measures analysis of variance indicated a significant time effect for changes in MS, CF, and FT, such that all improved after training. However, there were no significant training group or training group × time interactions. Sixteen weeks of combined AET/RET (1 × wk, 2 × wk, or 3 × wk) lead to significant improvements in MS, CF, exercise economy, and FT. However, there were no significant differences for MS, CF, or FT outcomes between groups.

Enhancement of Muscle Shortening Torque Preloaded with Muscle Lengthening is Joint-Specific.

Our cross-sectional study aimed to investigate joint specificity of concentric muscle torque enhancement after a maximum eccentric contraction for the knee versus ankle joints across two different movement velocities (120°/s and 180°/s). After a familiarization session, 22 healthy young adults randomly performed concentric (CONC) and maximum eccentric preloaded concentric (EccCONC) muscle strength tests of the knee extensors and ankle plantar flexors of the non-dominant leg on an isokinetic strength testing device. We calculated the ratio between EccCONC and CONC (EccCONC/CONC) for all the conditions as the marker of concentric muscle torque enhancement. Separate two-way (joints x velocity) within repeated measures ANOVAs were used to determine joint-specific torque differences at 120°/s and 180°/s. CONC and EccCONC were greater for the knee extensors versus ankle plantar flexors at 120°/s and 180°/s (32.86%-102%; p < 0.001 for both); however, EccCONC/CONC was greater for the ankle plantar flexors than knee extensors at 120°/s (52.4%; p < 0.001) and 180°/s (41.9%; p < 0.001). There was a trend of greater EccCONC/CONC for the knee extensors at 180°/s than 120°/s (6.6%; p = 0.07). Our results show that greater concentric muscle torque enhancement after a maximal eccentric contraction occurs for the ankle plantar flexors versus knee extensors. Whether the joint- specificity of concentric muscle torque enhancement after a maximal eccentric contraction differentially affects sports performance is unknown. Our data provide a reference framework to investigate joint-specific concentric muscle torque enhancement for general and clinical athletic populations.

Early time-restricted eating affects weight, metabolic health, mood, and sleep in adherent completers: A secondary analysis.

OBJECTIVE: Data are mixed on whether intermittent fasting improves weight loss and cardiometabolic health. Here, the effects of time-restricted eating (TRE) in participants who consistently adhered ≥5 d/wk every week were analyzed. METHODS: Ninety patients aged 25 to 75 years old with obesity were randomized to early TRE (eTRE; 8-hour eating window from 07:00 to 15:00) or a control schedule (≥12-hour window) for 14 weeks. A per-protocol analysis of weight loss, body composition, cardiometabolic health, and other end points was performed. RESULTS: Participants who adhered to eTRE ≥5 d/wk every week had greater improvements in body weight (-3.7 ± 1.2 kg; p = 0.003), body fat (-2.8 ± 1.3 kg; p = 0.04), heart rate (-7 ± 3 beats/min; p = 0.02), insulin resistance (-2.80 ± 1.36; p = 0.047), and glucose (-9 ± 5 mg/dL; p = 0.047) relative to adherers in the control group. They also experienced greater improvements in mood, including fatigue and anger; however, they self-reported sleeping less and taking longer to fall asleep. CONCLUSIONS: For those who can consistently adhere at least 5 d/wk, eTRE is a valuable approach for improving body weight, body fat, cardiometabolic health, and mood. Further research is needed to determine whether eTRE's effects of shortening sleep but reducing fatigue are healthful or not.

Impact of early time-restricted eating on diet quality, meal frequency, appetite, and eating behaviors: A randomized trial.

OBJECTIVE: Time-restricted eating (TRE) can reduce body weight, but it is unclear how it influences dietary patterns and behavior. Therefore, this study assessed the effects of TRE on diet quality, appetite, and several eating behaviors. METHODS: Adults with obesity were randomized to early TRE plus energy restriction (eTRE + ER; 8-hour eating window from 7:00 a.m. to 3:00 p.m.) or a control eating schedule plus energy restriction (CON + ER; ≥12-hour window) for 14 weeks. Food intake was assessed via the Remote Food Photography Method, while eating patterns, appetite, and eating behaviors were assessed via questionnaires. RESULTS: A total of 59 participants completed the trial, of whom 45 had valid food records. eTRE + ER did not affect eating frequency, eating restraint, emotional eating, or the consistency of mealtimes relative to CON + ER. eTRE + ER also did not affect overall diet quality. The intensity and frequency of hunger and fullness were similar between groups, although the eTRE + ER group was hungrier while fasting. CONCLUSIONS: When combined with a weight-loss program, eTRE does not affect diet quality, meal frequency, eating restraint, emotional eating, or other eating behaviors relative to eating over more than a 12-hour window. Rather, participants implement eTRE as a simple timing rule by condensing their normal eating patterns into a smaller eating window.

Spatiotemporal expression profiling of proteins in rat sciatic nerve regeneration using reverse phase protein arrays.

BACKGROUND: Protein expression profiles throughout 28 days of peripheral nerve regeneration were characterized using an established rat sciatic nerve transection injury model. Reverse phase protein microarrays were used to identify the spatial and temporal expression profile of multiple proteins implicated in peripheral nerve regeneration including growth factors, extracellular matrix proteins, and proteins involved in adhesion and migration. This high-throughput approach enabled the simultaneous analysis of 3,360 samples on a nitrocellulose-coated slide. RESULTS: The extracellular matrix proteins collagen I and III, laminin gamma-1, fibronectin, nidogen and versican displayed an early increase in protein levels in the guide and proximal sections of the regenerating nerve with levels at or above the baseline expression of intact nerve by the end of the 28 day experimental course. The 28 day protein levels were also at or above baseline in the distal segment however an early increase was only noted for laminin, nidogen, and fibronectin. While the level of epidermal growth factor, ciliary neurotrophic factor and fibroblast growth factor-1 and -2 increased throughout the experimental course in the proximal and distal segments, nerve growth factor only increased in the distal segment and fibroblast growth factor-1 and -2 and nerve growth factor were the only proteins in that group to show an early increase in the guide contents. As expected, several proteins involved in cell adhesion and motility; namely focal adhesion kinase, N-cadherin and ß-catenin increased earlier in the proximal and distal segments than in the guide contents reflecting the relatively acellular matrix of the early regenerate. CONCLUSIONS: In this study we identified changes in expression of multiple proteins over time linked to regeneration of the rat sciatic nerve both demonstrating the utility of reverse phase protein arrays in nerve regeneration research and revealing a detailed, composite spatiotemporal expression profile of peripheral nerve regeneration.

Weight loss and exercise training effect on oxygen uptake and heart rate response to locomotion.

Effects of resistance and aerobic training on the ease of physical activity during and after weight loss are unknown. The purpose of the study was to determine what effect weight loss combined with either aerobic or resistance training has on the ease of locomotion (net V[Combining Dot Above]O2 and heart rate). It is hypothesized that exercise training will result in an increased ease, lowers heart rate during locomotion. Seventy-three overweight premenopausal women were assigned to diet and aerobic training, diet and resistance training, or diet only. Subjects were evaluated while overweight, after diet-induced weight loss (average, 12.5 kg loss), and 1 year after weight loss (5.5 kg regain). Submaximal walking, grade walking, stair climbing, and bike oxygen uptake and heart rate were measured at all time points. Weight loss diet was 800 kcal per day. Exercisers trained 3 times per week during weight loss and 2 times per week during 1-year follow-up. Resistance training increased strength, and aerobic training increased maximum oxygen uptake. Net submaximal oxygen uptake was not affected by weight loss or exercise training. However, heart rate during walking, stair climbing, and bicycling was reduced after weight loss. No significant differences in reduction in heart rate were observed among the 3 treatment groups for locomotion after weight loss. However, during 1-year follow-up, exercise training resulted in maintenance of lower submaximal heart rate, whereas nonexercisers increased heart rate during locomotion. Results suggest that moderately intense exercise is helpful in improving the ease of movement after weight loss. Exercise training may be helpful in increasing the participation in free-living physical activity.

Effectiveness of Early Time-Restricted Eating for Weight Loss, Fat Loss, and Cardiometabolic Health in Adults With Obesity: A Randomized Clinical Trial.

Importance: It is unclear how effective intermittent fasting is for losing weight and body fat, and the effects may depend on the timing of the eating window. This randomized trial compared time-restricted eating (TRE) with eating over a period of 12 or more hours while matching weight-loss counseling across groups. Objective: To determine whether practicing TRE by eating early in the day (eTRE) is more effective for weight loss, fat loss, and cardiometabolic health than eating over a period of 12 or more hours. Design, Setting, and Participants: The study was a 14-week, parallel-arm, randomized clinical trial conducted between August 2018 and April 2020. Participants were adults aged 25 to 75 years with obesity and who received weight-loss treatment through the Weight Loss Medicine Clinic at the University of Alabama at Birmingham Hospital. Interventions: All participants received weight-loss treatment (energy restriction [ER]) and were randomized to eTRE plus ER (8-hour eating window from 7:00 to 15:00) or control eating (CON) plus ER (≥12-hour window). Main Outcomes and Measures: The co-primary outcomes were weight loss and fat loss. Secondary outcomes included blood pressure, heart rate, glucose levels, insulin levels, and plasma lipid levels. Results: Ninety participants were enrolled (mean [SD] body mass index, 39.6 [6.7]; age, 43 [11] years; 72 [80%] female). The eTRE+ER group adhered 6.0 (0.8) days per week. The eTRE+ER intervention was more effective for losing weight (-2.3 kg; 95% CI, -3.7 to -0.9 kg; P = .002) but did not affect body fat (-1.4 kg; 95% CI, -2.9 to 0.2 kg; P = .09) or the ratio of fat loss to weight loss (-4.2%; 95% CI, -14.9 to 6.5%; P = .43). The effects of eTRE+ER were equivalent to reducing calorie intake by an additional 214 kcal/d. The eTRE+ER intervention also improved diastolic blood pressure (-4 mm Hg; 95% CI, -8 to 0 mm Hg; P = .04) and mood disturbances, including fatigue-inertia, vigor-activity, and depression-dejection. All other cardiometabolic risk factors, food intake, physical activity, and sleep outcomes were similar between groups. In a secondary analysis of 59 completers, eTRE+ER was also more effective for losing body fat and trunk fat than CON+ER. Conclusions and Relevance: In this randomized clinical trial, eTRE was more effective for losing weight and improving diastolic blood pressure and mood than eating over a window of 12 or more hours at 14 weeks. Trial Registration: ClinicalTrials.gov Identifier: NCT03459703.

Circulating Levels of the Heparan Sulfate Proteoglycan Syndecan-4 Positively Associate with Blood Pressure in Healthy Premenopausal Women.

Syndecans (SDCs) are transmembrane proteins that are present on most cell types where they play a role in multiple physiological processes, including cell-matrix adhesion and inflammation. Growing evidence suggests that elevated levels of both shed SDC1 and SDC4 are associated with hypertension and cardiovascular diseases, but their relationships with cardiovascular risk factors in healthy individuals are unknown. The primary objective of this study was to investigate whether serum levels of SDC4 and SDC1 were associated with body composition, hemodynamic parameters, pro-inflammatory cytokine concentrations, and urinary noradrenaline and dopamine levels in healthy women (17 African American and 20 European American) between the ages of 20 and 40 years old. Univariate analyses revealed only a significant (p < 0.05) inverse correlation between serum SDC1 and body fat percentage. On the other hand, serum SDC4 was positively correlated with systolic blood pressure, diastolic blood pressure, and urinary levels of noradrenaline and dopamine. Serum SDC4 was also a significant predictor of systolic blood pressure in a multivariate regression model that included fat-free mass and urinary dopamine levels as significant independent variables. The result did not change even adjusting for race. Our findings indicate that SDC4 has an important role in the physiological regulation of blood pressure.

Role of sagittal reformatted computed tomographic images in the evaluation of orbital floor fractures.

BACKGROUND: The sagittal plane computed tomographic (CT) scan has been proposed as the most important radiologic view in the diagnosis of orbital floor fractures. Before the advent of high-resolution CT, several articles were published in the radiology literature debating the need for direct sagittal views, which required cumbersome patient positioning. Today, the ability to easily create high-quality sagittal reformations requires reassessment of the importance of this view in the evaluation of orbital floor fractures. MATERIALS AND METHODS: Computed tomographic studies of 24 orbital floor fractures for which coronal and sagittal images were available were included. Five independent reviewers evaluated all image sets and recorded maximum fracture width, depth, posterior shelf length (PSL), and presence of medial wall fracture and of trap door deformity. Direct fracture width measurements were obtained via coronal images, whereas depth and PSL were measured directly in the sagittal plane. Indirect measurements in a given plane were obtained by counting the number of slices in which the fracture was present and multiplying by the slice thickness. Cronbach alpha analysis was used to provide an intraclass correlation coefficient, where greater values signify less interreviewer variability. RESULTS: The Cronbach alpha values for width, depth, and PSL were 64%, 59%, and 85% in the coronal view and 76%, 55%, and 51% in the sagittal view, respectively. The alpha values for presence/absence of medial wall fracture and trap door deformity were greater in the coronal view at 73% and 55%, respectively. The intrareviewer variability was not significantly correlated with the degree of patient rotation or CT scan slice thickness. The interreviewer variability was significantly less among attending reviewer then resident reviewers. CONCLUSIONS: There was less interreviewer variability when the measured variables were assessed indirectly (width was best assessed in the sagittal plane, and depth and PSL were best assessed in the coronal view). These findings support the idea that additional views aid the surgeon's ability to further define fracture anatomy than might be possible with any single view, thereby improving preoperative planning and reconstructive strategies.

Parasite density in severe malaria in Colombia.

BACKGROUND: Colombia has officially adopted the parasite density levels of severe malaria established by the WHO (>50,000 parasites/µl). These values have been inferred from areas of high transmission in Africa and are not consistent with the dynamics of low and unstable transmission in Colombia. The objective of this study was therefore to determine the parasite density values observed in patients with severe malaria and their distribution in the different ecoepidemiological regions of Colombia. METHODS: A retrospective and descriptive study of confirmed cases of severe malaria was conducted in endemic areas of malaria in Colombia over the period 2014-2017. Data were collected from secondary sources of the Subnational Programs of Malaria Prevention and Control. Person, place, and time variables were selected. The official definition of severe malaria was adopted, and compliance with these criteria was determined. Univariate and bivariate analyses were conducted with absolute and relative frequency measures, and the relevant statistical tests were applied. RESULTS: The overall parasite density values in Colombia showed a geometric mean of 5,919 parasites/µl (95% CI: 5,608-6,248). By parasite species, the values were 6,151 (95% CI: 5,631-6,718) for Plasmodium falciparum and 5,815 (95% CI: 5,428-6,230) for Plasmodium vivax. The highest parasite density values were recorded in the Amazon ecoepidemiological region (8,177; 95% CI: 6,015-11,116), and the lowest values were recorded in the Andean region (5,026; 95% CI: 2,409-10,480). CONCLUSIONS: In endemic areas of low and unstable malaria transmission in the Colombian territory, the parasite density levels observed in populations with severe malaria are lower than the officially established values. The parasite density criterion is not really a relevant criterion for the definition of severe cases in Colombia and it certainly not be used to make a clinical decision about the severity of the disease.

Sarcopenia and Its Implications for Metabolic Health.

Sarcopenia not only affects the ability to lead an active lifestyle but also contributes to increased obesity, reduced quality of life, osteoporosis, and metabolic health, in part due to reduced locomotion economy and ease. On the other hand, increased obesity, decreased quality of life, and reduced metabolic health also contribute to sarcopenia. The purpose of this mini-review is to discuss the implications sarcopenia has for the development of obesity and comorbidities that occur with aging.

Exercise training and/or diet on reduction of intra-abdominal adipose tissue and risk factors for cardiovascular disease.

BACKGROUND/OBJECTIVES: To test the effects of weight loss with and without exercise training (aerobic or resistance) on intra-abdominal adipose tissue (IAAT) and risk factors for cardiovascular disease (CVD). Additionally, CVD risk factors was evaluated before and after weight loss using previously established IAAT cut-points. SUBJECTS/METHODS: One hundred twenty-two overweight premenopausal women were randomly assigned to one of three groups: (1) diet only (Diet); (2) diet and aerobic training (Diet + AT); or (3) diet and resistance training (Diet + RT); until a BMI of < 25 kg/m2 was reached. Computerized tomography was used to measure IAAT and blood lipids were measured by assay. Evaluations were made before and after weight loss. RESULTS: Though no group-by-time effects were found after weight loss, we observed significant time effects for: IAAT (-38.0%, P < 0.001), total cholesterol (TC) (-2.2%, P = 0.008), low-density lipoprotein cholesterol (LDL-C) (-4.8%, P < 0.001), high-density lipoprotein cholesterol (HDL-C) (+20.2%, P < 0.001), triglycerides (-18.7%, P < 0.001), TC/HDL-C (-16.3%, P < 0.001), and LDL-C/HDL-C (-18.0%, P < 0.001). Following weight loss, 40.2% of all participants reduced IAAT to < 40 cm2 (IAAT associated with low CVD risk). Furthermore, only 2.5% of participants had an IAAT > 110 cm2 (IAAT associated with high CVD risk) after weight loss. We also observed that decreases of IAAT were associated with decreased CVD risk factors after weight loss independent of race, changes in %fat mass and changes in maximal oxygen uptake. CONCLUSIONS: Caloric restriction leading to significant weight loss with or without exercise training appears to be equally effective for reducing IAAT and CVD risk factors.

Combined Aerobic and Resistance Training Increases Stretch- Shortening Cycle Potentiation and Walking Economy in Postmenopausal Women.

PURPOSE: Secondary analyses were performed to test whether combined aerobic and resistance training altered walking economy (i.e., net oxygen uptake) and/or stretch-shortening cycle potentiation (SSCP). A further objective was to determine if walking economy and SSCP were related before or after training. METHODS: Ninety-two postmenopausal women were enrolled wherein 76 completed 16 weeks of supervised aerobic and resistance training. Participants were randomized to one of three training groups based on frequencies: (a) 1 d⋅wk-1 (n = 23); (b) 2 d⋅wk-1 (n = 30) or; (c) 3 d⋅wk-1 (n = 23). Following assessments were performed at baseline and post-training. Indirect calorimetry was used to measure maximal oxygen uptake () and walking economy (submaximal - resting = net ) during a graded exercise test and steady-state treadmill task, respectively. SSCP was determined by measuring the difference between a concentric (CO) and counter-movement (CM) leg press throw. RESULTS: , walking economy, CO and CM velocity were significantly improved (p < 0.05) for all training groups, however; no time by group interactions were observed. Paired t-tests revealed participants exercise training 2 d⋅wk-1 exhibited a significant time effect for SSCP (+0.04 ± 0.09 ms-1; p = 0.03). At baseline, multiple linear regression showed a negative relationship between walking net and SSCP (r = -0.22; p < 0.04) adjusted for relative proportion of . No such relationship was found post-training. CONCLUSION: Among older postmenopausal women, our results indicate that irrespective of frequency of training, 16 weeks of combined aerobic and resistance exercise training increased ease of walking and economy. Additionally, only participants exercising 2 d⋅wk-1 exhibited significant improvement in SSCP.

Regional differences in an established population of invasive Indo-Pacific lionfish (Pterois volitans and P. miles) in south Florida.

About nine years ago (circa 2009), Indo-Pacific lionfishes (Pterois volitans and P. miles) invaded the south Florida coral reef ecosystem. During the intervening period of time, there has been substantial research on their biology, life history, demography, and habitat preferences; however, little is known concerning their regional population status and trends in the region. Here, we use a large-scale fisheries independent reef fish visual survey to investigate lionfish population status among three south Florida regions: Dry Tortugas, Florida Keys, and southeast Florida. Density estimates (ind ha-1) have been relatively stable since 2012, and are lower than other areas reported in the western Atlantic and Caribbean Sea. Low, stable population densities in south Florida suggest there may be a natural mechanism for lionfish population control. In the Dry Tortugas, lionfish density in 2016 was significantly lower (0.6 ind ha-1 ± 0.15 SE) than the two other south Florida regions. The Dry Tortugas region has the highest percentage of marine protected areas, the lowest level of exploitation, and thus the highest densities of potential lionfish predators and competitors. In the Florida Keys and southeast Florida in 2016, lionfish densities were greater (5.4 ind ha-1 ± 1.0 SE and 9.0 ± 2.7 SE, respectively) than the Dry Tortugas. Fishing pressure on lionfish was higher in these two regions, but densities of several potential predators and competitors were substantially lower. Despite relatively low regional lionfish densities that can be attributed to some combination of fishing mortality and natural biocontrol, lionfish are still well established in the south Florida coral reef ecosystem, warranting continued concern.

Serum Tumor Necrosis Factor-alpha associates with Myocardial Oxygen Demand and Exercise Tolerance in Postmenopausal Women.

The functional implications of serum tumor necrosis factor-alpha (TNF-α), a marker of oxidative stress, on hemodynamic parameters at rest and during physical exertion are unclear. The aims of this investigation were to examine the independent associations of TNF-α on myocardial oxygen demand at rest and during submaximal exercise, while also evaluating the association of TNF-α on exercise tolerance. Forty, postmenopausal women, provided blood samples and completed a modified-Balke protocol to measure maximal oxygen uptake (VO2max). Large artery compliance was measured by pulse contour analyses while rate-pressure product (RPP), an index of myocardial oxygen demand, was measured at rest and during two submaximal workloads (i.e., ≈55% and ≈75% VO2max). RPP was calculated by dividing the product of heart rate and systolic blood pressure (via auscultation) by 100. Exercise tolerance corresponded with the cessation of the graded exercise test. During higher-intensity exertion, ≈75% VO2max, multiple linear regression revealed a positive association (r = 0.43; p = 0.015) between TNF-α and RPP while adjusting for maximal heart rate, VO2max, large artery compliance, and percent body fat. Path analyses revealed a significant indirect effect of large artery compliance on exercise tolerance through TNF-α, ß = 0.13, CI [0.03, 0.35], indicating greater levels of TNF-α associated with poorer exercise tolerance. These data suggest TNF-α independently associates with myocardial oxygen demand during physical exertion, thus highlighting the utility of higher-intensity efforts to expose important phenomena not apparent at rest. TNF-α also appears to be indirectly associated with the link between large artery compliance and exercise tolerance.