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Correct and revised version: We also consulted a research reference librarian who works at the University of Alabama at Birmingham to verify the article list using the same search terms. Incorrect version: We also consulted a research reference librarian who works at XXXXXXXX to verify the article list using the same search terms. The online version of the original article can be found at https://doi.org/10.1186/s12891-023-06739-6. [Extracted from the article]

Introduction: Resting energy expenditure (REE) increases after an intense exercise; however, little is known concerning mechanisms. Purpose: The purpose of this study was to determine effects of a single bout of moderate-intensity continuous (MIC) aerobic exercise, or high-intensity interval (HII) exercise on REE under energy balance conditions. Methods: Thirty-three untrained premenopausal women were evaluated at baseline, after 8-16 wk of training, 22 h after either MIC (50% peak VO2) or HII (84% peak ...O2). Participants were in a room calorimeter during and after the exercise challenge. Food intake was adjusted to obtain energy balance across 23 h. REE was measured after 22 h after all conditions. Twenty-three-hour urine norepinephrine concentration and serum creatine kinase activity (CrKact) were obtained. Muscle biopsies were obtained in a subset of 15 participants to examine muscle mitochondrial state 2, 3, and 4 fat oxidation. Results: REE was increased 22 h after MIC (64 ± 119 kcal) and HII (103 ± 137 kcal). Markers of muscle damage (CrKact) increased after HII (9.6 ± 25.5 U⋅L-1) and MIC (22.2 ± 22.8 U⋅L-1), whereas sympathetic tone (urine norepinephrine) increased after HII (1.1 ± 10.6 ng⋅mg-1). Uncoupled phosphorylation (states 2 and 4) fat oxidation were related to REE (r = 0.65 and r = 0.55, respectively); however, neither state 2 nor state 4 fat oxidation increased after MIC or HII. REE was not increased after 8 wk of aerobic training when exercise was restrained for 60 h. Conclusions: Under energy balance conditions, REE increased 22 h after both moderate-intensity and high-intensity exercise. Exercise-induced muscle damage/repair and increased sympathetic tone may contribute to increased REE, whereas uncoupled phosphorylation does not. These results suggest that moderate- to high-intensity exercise may be valuable for increasing energy expenditure for at least 22 h after the exercise. [ABSTRACT FROM AUTHOR]

We have previously shown that Achilles tendon length is related to walking economy on the flat, presumably because of increased stretch-shortening cycle elastic energy savings. In addition, greater walking economy in African American (AA) women compared to European American (EA) women is explained by longer Achilles tendons in AA women. The purposes of this study were to determine whether economy while walking up a grade and during isometric plantar flexion, two tasks expected to produce proportionately less energy savings from elastic savings are different between AA and EA women. We evaluated walking economy at 4.8 km/h at 0 and 2.5% grade in 48 AA and 48 EA premenopausal women. Plantar flexor muscle metabolic economy (force/ATP) was also evaluated using (31) phosphate magnetic resonance spectroscopy ((31)P-MRS). AA women walked on the flat more economically (net VO(2), AA 8.3 and EA 8.9 ml kg(-1) min(-1), P = 0.04). No significant ethnic differences were observed while walking up a 2.5% grade or in (31)P-MRS determined plantar flexor muscle metabolic economy. These data support our previous study's suggestion that AA women are more economical while walking on the flat. On the other hand, in activities in which stretch-shortening cycle elastic energy savings would be expected to be reduced (grade walking and isometric force production), no differences in economy during grade walking or isometric force production were observed suggesting that biomechanical, i.e. stretch-shortening cycle elastic energy savings differences rather biochemical differences contribute to the better flat walking economy observed in AA women. [ABSTRACT FROM AUTHOR]

The article describes the importance of place-based learning in teaching students about the Native American legends in the Pacific Northwest. It states that place-based literacy learning is considered as an innovation in education that utilizes local literacy artifacts to study the cultural, political-economic, and environmental connections in the community. It states that learning about the Native American legends using place-based literacy learning can be taught in language arts classrooms.

Routine exercise training is known to improve health outcomes in individuals with obesity (IO); however it remains challenging for IO to adhere to exercise programs. Thus, it is critical to identify novel strategies that can improve exercise capacity (EC) and lead to greater adherence in IO. Beetroot juice (BRJ), high in dietary nitrate, has been shown to improve exercise performance in athletes, individuals with cardiopulmonary diseases, and non-obese lean individuals. These improvements may be explained by reduced oxygen uptake (VO2) during exercise, enhanced blood flow, and greater mitochondrial efficiency. To date, we are aware of no studies comparing the effects of BRJ, sodium nitrate (NaNO3), denitrilized BRJ (PLA), and control (CON) conditions for improving EC and cardiometabolic health in IO. PURPOSE: to determine if BRJ improves EC, exercise efficiency (EE) and cardiometabolic health in IO and identify possible mechanisms of action. METHODS: Vascular health (blood pressure and arterial elasticity), VO2 on a cycle ergometer during submaximal- and maximal- exercise, and time to exhaustion (TTE) were assessed in 16 sedentary IO in a crossover design for the following 4 conditions: 1) consumption of BRJ, 2) NaNO3, 3) PLA, or 4) CON. Study visits were at least 72 hours apart. RESULTS: A significant treatment effect was observed for submaximal exercise VO2 (p=0.003), and TTE (seconds) (p=0.035). Post hoc analyses demonstrated a lower VO2 during submaximal exercise in BRJ compared to PLA (P=0.009) NaNO3 (P=0.042) and CON (0.009). TTE was greater between BRJ and CON (P=0.029) with no other differences observed between conditions. No other significant changes were observed for other exercise or vascular health measures. CONCLUSIONS: In this analysis of 16 IO, consumption of BRJ improved EE during submaximal cycling exercise by 5.28% compared to PLA, 5.91% compared to the NaNO3, and 4.22% compared to CON. Finally, BRJ resulted in a 19% improvement in TTE compared to CON condition. These results suggest that consumption of BRJ may improve cycling efficiency and exercise capacity in IO. This study was funded by a School of Education Faculty Development Grant awarded to G. Fisher. At the time of this study C. Behrens was supported by a NIH T-32grant (T32HL105349) awarded by the Heart, Lung and Blood Disease Institute (NHLBI) [ABSTRACT FROM AUTHOR]

Physical inactivity and poor dietary choices contribute to the rise in cardiometabolic diseases in the United States. It remains critical to identify strategies that may mitigate the negative impact of these behaviors. Several studies have shown that the consumption of dietary inorganic nitrate may improve vascular health and glucose regulation in animal models and some human studies. However, the improvements in glucose regulation have yet to be corroborated in humans with type 2 diabetes (T2D). Therefore, the purpose of this study was to assess the acute effects of beetroot juice (BRJ) on glycemic and hemodynamic responses in individuals with T2D while controlling for medication. Seven participants with a clinical diagnosis of T2D were recruited into this study and were temporarily removed from blood pressure- and glucose-lowering medications. Hemodynamic measurements (pulsewave velocity) and an oral glucose tolerance test (glycemic response) were measured following consumption of either BRJ or a denitrolized placebo. Saliva and blood samples were collected at baseline and two and four hours post supplementation to measure changes in nitrate and nitrite concentrations. We detected significant improvements in total plasma glucose exposure ( p = 0.022) and the SVR change score ( p = 0.009) in the BRJ condition. This study demonstrated that BRJ consumption can improve oral glucose tolerance in individuals with T2D while controlling for medication; however, future larger-cohort randomized controlled trials are needed to confirm if BRJ is a viable treatment for glucose control in individuals with T2D.

Background: Children with mobility disabilities, including those with cerebral palsy, have limited options and limited time to exercise to manage their cardiometabolic health and cardiorespiratory fitness. Regular cardiovascular exercise during childhood is a critical health behavior for preventing health decline in adulthood. Thus, there is an urgent need for accessible, age-appropriate, convenient exercise modalities in this group. Sprint-intensity interval training (SIT), combined with telehealth procedures, may be ideal for children with disabilities. SIT includes repetitive bouts of maximal exercise effort combined with rest periods, which can be effective in eliciting comparable results to moderate-exercise training with very short training durations., Objective: This phase 1 pilot feasibility randomized controlled trial aims to investigate the potential effects of a 12-week SIT program on indicators of cardiorespiratory fitness and cardiometabolic health among children with cerebral palsy. An ancillary aim is to evaluate the feasibility of the program through several process feasibility metrics., Methods: This study uses a 2-armed parallel group design. A total of 50 physically inactive children with cerebral palsy (aged 6-17 years) will be randomly allocated into 1 of 2 groups: a 12-week SIT or a waitlist control group that continues habitual activity for 12 weeks. The SIT prescription includes 3 tele-supervised sessions per week with 30 repeated sequences of 4 seconds of maximal arm exercise, with active recovery, warm-up, and cooldown periods (for an approximately 20-minute total session). SIT includes guided videos with child-themed arm routines and music. The exercise sessions will be remotely supervised through a web-based videoconference application and include safety monitoring equipment. Outcomes are measured at pre- and postintervention (weeks 0 and 13, respectively). Health outcome measures include peak oxygen consumption (VO 2 peak), measured by a graded exercise test; high-sensitivity C-reactive protein and blood insulin, hemoglobin A 1c , triglycerides, and cholesterol using a finger stick dried blood spot test; blood pressure, using a sphygmomanometer; and body composition (total mass, total lean mass, tissue % lean, and tissue % fat) using dual x-ray absorptiometry. Feasibility will be evaluated by the following metrics: adverse events or problems experienced throughout the intervention related to participant safety; perceived enjoyment; and recruitment, enrollment, and attrition rates., Results: Recruitment procedures started in November 2023. All data are anticipated to be collected by February 2025. Full trial results are anticipated to be analyzed and submitted for publication by March 2025. Secondary analyses of data will be subsequently published., Conclusions: This trial tests an accessible and low-cost exercise program that leverages principles of high-intensity exercise to provide a convenient program for children with physical disabilities. Knowledge obtained from this study will inform the development of a larger trial for improving the cardiometabolic health, cardiorespiratory fitness, and well-being of children with physical disabilities., Trial Registration: ClinicalTrials.gov NCT05619211; https://clinicaltrials.gov/study/NCT05619211., International Registered Report Identifier (irrid): DERR1-10.2196/56499., (©Byron Lai, Robert A Oster, Drew Davis, Larsen Bright, Gordon Fisher, Jereme Wilroy, Yumi Kim, Raven Young, Ashley Wright, Tanvee Sinha, James H Rimmer. Originally published in JMIR Research Protocols (https://www.researchprotocols.org), 05.03.2024.)

The Army Combat Fitness Test (ACFT) is used to evaluate the fitness level of potential Cadets for military readiness. The purpose of this study was to evaluate the effectiveness of the exercise training program implemented by an Army Reserve Officers' Training Corps (ROTC) program to gauge the performance metrics of the ACFT., Methods: Twenty-six student Cadets of the ROTC at the University of Alabama at Birmingham (UAB) program participated in the study. Over an 8-month period, the ROTC Cadets trained on campus three days per week. Training was performed in a circuit training format and each participant cycled through each of the four training stations (Strength, Conditioning, Core, and Endurance) for 15 minutes each session (for a total training time of 60 minutes). Each Cadet had body mass and body composition assessed as well as each component of the ACFT [maximum dead lift (MDL), standing power throw (SPT), hand release push-up (HRP), sprint-drag-carry (SDC), leg tuck/plank (LTK/PLK), and 2-mile run (2MR)]. Each variable was evaluated at three time points (pre-, mid-, and post-training program)., Results: There was a significant difference in the 2MR score between time points [F(2,50) = 4.530, p = .016, η 2 = 0.153] with a significant difference between time point at pre- and post-training ( p = .02). No other variables displayed a significant change: body mass ( p = .741), body fat percentage ( p = .238), MDL ( p = .061), SPT ( p = .308), HRP ( p = .126), SDC ( p = 0.132), LTK/PLK ( p = 0.583)., Conclusion: The results of this study suggest that the short-term training program used improves 2MR, but not other components of the ACFT over the course of an academic year.

Exogenous ketone ester and ketone ester mixed with ketone free acid formulations are rapidly entering the commercial marketspace. Short-term animal and human studies using these products suggest significant potential for primary or secondary prevention of a number of chronic disease conditions. However, a number of questions need to be addressed by the field for optimal use in humans, including variable responses among available exogenous ketones at different dosages; frequency of dosing; and their tolerability, acceptability, and efficacy in long-term clinical trials. The purpose of the current investigation was to examine the tolerability, acceptability, and circulating R-beta-hydroxybutyrate (R-βHB) and glucose responses to a ketone monoester (KME) and ketone monoester/salt (KMES) combination at 5 g and 10 g total R-βHB compared with placebo control (PC). Fourteen healthy young adults (age: 21 ± 2 years, weight: 69.7 ± 14.2 kg, percent fat: 28.1 ± 9.3%) completed each of the five study conditions: placebo control (PC), 5 g KME (KME5), 10 g KME (KME10), 5 g (KMES5), and 10 g KMES (KMES10) in a randomized crossover fashion. Circulating concentrations of R-βHB were measured at baseline (time 0) following an 8-12 h overnight fast and again at 15, 30, 60, and 120 min following drink ingestion. Participants also reported acceptability and tolerability during each condition. Concentrations of R-βHB rose to 2.4 ± 0.1 mM for KME10 after 15 min, whereas KMES10 similarly peaked (2.1 ± 0.1 mM) but at 30 min. KME5 and KMES5 achieved similar peak R-βHB concentrations (1.2 ± 0.7 vs. 1.1 ± 0.5 mM) at 15 min. Circulating R-βHB concentrations were similar to baseline for each condition by 120 min. Negative correlations were observed between R-βHB and glucose at the 30 min time point for each condition except KME10 and PC. Tolerability was similar among KME and KMES, although decreases in appetite were more frequently reported for KMES. Acceptability was slightly higher for KMES due to the more frequently reported aftertaste for KME. The results of this pilot investigation illustrate that the KME and KMES products used increase circulating R-βHB concentrations to a similar extent and time course in a dose-dependent fashion with slight differences in tolerability and acceptability. Future studies are needed to examine variable doses, frequency, and timing of exogenous ketone administration for individuals seeking to consume ketone products for health- or sport performance-related purposes.

Background: Cardiovascular disease is one of the main causes of death in the United States, and hypertension is a primary risk factor. Therefore, the primary causes of hypertension need to be identified so they may be addressed for treatment. The purpose of this study was to compare blood pressure with hemodynamic values and identify factors that may explain blood pressure differences between a cohort of healthy normotensive younger and older women., Methods: Participants were 49 young (age: 33.8 ± 5.9) and 103 old (age: 65.8 ± 4) who were non-hypertensive, had no previous history of heart disease or type 2 diabetes, body mass index less than 30 kg/m 2 , normal electrocardiography response at rest and during exercise, nonsmokers, and no use of medications known to affect cardiovascular or metabolic function. Body composition measured by dual-energy X-ray absorptiometry. Hemodynamic values measured by non-invasive pulse wave velocity through radial artery tonometry. Markers of inflammation measured through blood sample analysis., Results: Significant differences exist between young and old groups in %fat (P < 0.001), systolic blood pressure (SBP) (P = 0.001), large artery elasticity (P = 0.005), small artery elasticity (P < 0.001), systemic vascular resistance (P = 0.004), total vascular impedance (P < 0.001), estimated cardiac output (P < 0.001), and tumor necrosis factor-⍺ (TNF-⍺) (P < 0.001). Using ANCOVA the difference in SBP between age groups was no longer significant after adjusting for small artery elasticity (P < 0.001) and TNF-⍺ (P = 0.041)., Conclusions: These data demonstrate that blood pressure and vascular hemodynamic measures differ significantly between young and old women independent of body composition. Furthermore, these differences may be explained by the inflammation marker TNF-⍺ and/or small artery elasticity., (© 2021. The Author(s).)

Objective: Insulin sensitivity is lower in African American (AA) versus Caucasian American (CA). We tested the hypothesis that lower insulin sensitivity in AA could be explained by mitochondrial respiratory rates, coupling efficiency, myofiber composition, or H 2 O 2 emission. A secondary aim was to determine whether sex affected the results., Methods: AA and CA men and women, 19-45 years, BMI 17-43 kg m 2 , were assessed for insulin sensitivity (SI Clamp ) using a euglycemic clamp at 120 mU/m 2 /min, muscle mitochondrial function using high-resolution respirometry, H 2 O 2 emission using amplex red, and % myofiber composition., Results: SI Clamp was greater in CA (p < 0.01) and women (p < 0.01). Proportion of type I myofibers was lower in AA (p < 0.01). Mitochondrial respiratory rates, coupling efficiency, and H 2 O 2 production did not differ with race. Mitochondrial function was positively associated with insulin sensitivity in women but not men. Statistical adjustment for mitochondrial function, H 2 O 2 production, or fiber composition did not eliminate the race difference in SI Clamp ., Conclusion: Neither mitochondrial respiratory rates, coupling efficiency, myofiber composition, nor mitochondrial reactive oxygen species production explained lower SI Clamp in AA compared to CA. The source of lower insulin sensitivity in AA may be due to other aspects of skeletal muscle that have yet to be identified., (© 2021 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

Background: Race differences in body composition and fat distribution may in part explain the differences in insulin sensitivity and the disproportionate burden of type 2 diabetes in African Americans., Objective: To determine if differences in body composition and fat distribution explain race differences in insulin sensitivity and identify obesity measures that were independently associated with insulin sensitivity., Methods: Participants were 113 lean, overweight, and obese African-American and Caucasian-American adults without diabetes. Skeletal muscle insulin sensitivity was determined using a hyperinsulinemic-euglycemic clamp (SIClamp, insulin rate:120 mU/m2/min). Subcutaneous abdominal adipose tissue (SAAT), intra-abdominal adipose tissue (IAAT), and liver fat were measured by MRI; leg fat, total fat, and lean mass were measured by DXA., Results: Race-by-adiposity interactions were significant in cross-sectional analyses utilizing multiple linear regression models for SIClamp (P < 0.05); higher BMI, fat mass, SAAT, leg fat, and liver fat were associated with lower SIClamp in Caucasian Americans but not African Americans. Race-by-IAAT interaction was not significant (P = 0.65). A central fat distribution (SAAT adjusted for leg fat) was associated with lower SIClamp in African Americans (β = -0.45, SE = 0.11, P < 0.001) but not Caucasian Americans (β = -0.42, SE = 0.30, P = 0.17). A peripheral fat distribution (leg fat adjusted for IAAT/SAAT) was associated with a higher SIClamp in African Americans (β = 0.11, SE = 0.05, P = 0.02) but lower SIClamp in Caucasian Americans (β = -0.28, SE = 0.14, P = 0.049). Lean mass was inversely associated with SIClamp in African Americans (β = -0.05, SE = 0.03, P = 0.04) but not Caucasian Americans (β = 0.08, SE = 0.05, P = 0.10) in the model for leg fat., Conclusions: Measures of overall adiposity were more strongly associated with SIClamp in Caucasian Americans, whereas body fat distribution and lean mass showed stronger correlations with SIClamp in African Americans. Insulin sensitivity may have a genetic basis in African Americans that is reflected in the pattern of body fat distribution. These findings suggest a race-specific pathophysiology of insulin resistance, which has implications for the prevention of diabetes and related cardiometabolic diseases., (Copyright © The Author(s) 2019.)

Aerobic capacity is negatively related to locomotion economy. The purpose of this paper is to determine what effect aerobic exercise training has on the relationship between net cycling oxygen uptake (inverse of economy) and aerobic capacity [peak oxygen uptake (V̇o 2peak )], as well as what role mitochondrial coupled and uncoupled respiration may play in whole body aerobic capacity and cycling economy. Cycling net oxygen uptake and V̇o 2peak were evaluated on 31 premenopausal women before exercise training (baseline) and after 8-16 wk of aerobic training. Muscle tissue was collected from 15 subjects at baseline and post-training. Mitochondrial respiration assays were performed using high-resolution respirometry. Pre- ( r  = 0.46, P < 0.01) and postexercise training ( r  = 0.62, P < 0.01) V̇o 2peak and cycling net oxygen uptake were related. In addition, uncoupled and coupled fat respiration were related both at baseline ( r  = 0.62, P < 0.01) and post-training ( r  = 0.89, P < 01). Post-training coupled ( r  = 0.74, P < 0.01) and uncoupled carbohydrate respiration ( r  = 0.52, P < 05) were related to cycle net oxygen uptake. In addition, correlations between V̇o 2peak and cycle net oxygen uptake persist both at baseline and after training, even after adjusting for submaximal cycle respiratory quotient (an index of fat oxidation). These results suggest that the negative relationship between locomotion economy and aerobic capacity is increased following exercise training. In addition, it is proposed that at least one of the primary factors influencing this relationship has its foundation within the mitochondria. Strong relationships between coupled and uncoupled respiration appear to be contributing factors for this relationship. NEW & NOTEWORTHY The negative relationship between cycle economy and aerobic capacity is increased following exercise training. The strong relationship between coupled and uncoupled respiration, especially after training, appears to be contributing to this negative relationship between aerobic capacity and cycling economy, suggesting that mitochondrial economy is not increased following aerobic exercise training. These results are suggestive that training programs designed to improve locomotion economy should focus on changing biomechanics.

Background: Recent studies in nondisabled individuals have demonstrated that low-volume high-intensity interval training (HIIT) can improve cardiometabolic health similar to moderate-intensity training (MIT) despite requiring 20% of the overall time commitment. To date, there have been no studies assessing the effects of HIIT for improving cardiometabolic health in individuals with SCI. Objectives: The primary purpose of this pilot study was to compare the effects of 6 weeks of low-volume HIIT vs MIT using arm crank ergometer exercise to improve body composition, cardiovascular fitness, glucose tolerance, blood lipids, and blood pressure in a cohort of individuals with longstanding SCI. Methods: Participants were randomized to 6 weeks of HIIT or MIT arm crank exercise training. Aerobic capacity, muscular strength, blood lipids, glucose tolerance, blood pressure, and body composition were assessed at baseline and 6 weeks post training. Results: Seven individuals (6 male, 1 female; n = 3 in MIT and n = 4 in HIIT; mean age 51.3 ± 10.5 years) with longstanding SCI completed the study. The preliminary findings from this pilot study demonstrated that individuals with SCI randomized to either 6 weeks of HIIT or MIT displayed improvements in (a) insulin sensitivity, (b) cardiovascular fitness, and (c) muscular strength ( p < .05). However, MIT led to greater improvements in arm fat percent and chest press strength compared to HIIT ( p < .05). Conclusion: No differences between MIT and HIIT were observed. Both conditions led to improvements in insulin sensitivity, aerobic capacity, muscle strength, and blood lipids in individuals with SCI. Future larger cohort studies are needed to determine if the shorter amount of time required from HIIT is preferable to current MIT exercise recommendations., Competing Interests: Conflicts of Interest G. Fisher reports grants from UAB/Lakeshore Research Collaborative during the conduct of the study.

Exercise is known to improve insulin sensitivity (SI); however, studies to date have been confounded by negative energy deficits after exercise., Purpose: The primary objective of this study was to assess the effect of 8 to 16 wk of aerobic exercise training on the SI of untrained women under rigorously controlled energy-balanced conditions. The secondary objective was to determine if one acute bout of moderate-intensity continuous (MIC) or high-intensity interval (HII) exercise further affected SI., Methods: Insulin sensitivity was assessed in 28 untrained women at baseline, after 8 to 16 wk of training with no-exercise (NE) before assessment, 22 h after MIC (50% V˙O2peak), and 22 h after HII (84% V˙O2peak) using a hyperinsulinemic-euglycemic clamp. Participants were in a whole-room indirect calorimeter during each condition, and food intake was adjusted to ensure energy balance across 23 h before each clamp., Results: There were no significant differences in acute energy balance between each condition. Results indicated a significant main effect of time, such that SI was higher during the HII condition compared with both baseline and NE (P < 0.05). No significant differences in SI were observed after NE or MIC., Conclusions: Widely reported improvements in SI in response to chronic exercise training may be mediated in part by shifts in energy balance. However, an acute bout of HII exercise may increase SI even in the context of energy balance.

Youth with inflammatory bowel disease (IBD) demonstrate deficits in lean mass (LM) placing them at increased risk for future health problems, including reduction of bone mass and impaired bone architecture. Research suggests that deficits in LM are multifactorial, including influences from the disease and its treatment, and health behaviors such as diet and physical activity. Based on a systematic literature review examining factors related to LM deficits in IBD, this article presents a conceptual model to explain the development of LM in youth with IBD. The model considers predictors of LM across 4 domains: demographic; medical; diet; and physical activity. Much existing research is cross-sectional, but suggests multiple factors work together to promote or inhibit LM accrual in youth with IBD. The conceptual model, developed based on empirical findings to date, can be used to understand and further elucidate the process through which LM is developed and maintained, to inform the development of empirically supported clinical interventions, and to guide future research objectives and priorities.

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.

Age-related declines in health and function make locomotion increasingly difficult leading to reductions in non-exercise activity thermogenesis (NEAT), skeletal muscle size and strength, and increased adiposity. Exercise is an important strategy to attenuate loss of function through the life cycle. Despite claims to the contrary, high-intensity exercise is important for the prevention of obesity and sarcopenia with advancing age. Therefore, the purpose of this mini-review is to present literature supporting the contention that low volume, high-intensity aerobic and/or resistance training can slow sarcopenia, sustain ease of movement, stimulate NEAT, and attenuate the accretion of fat mass., (Copyright © 2017 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Background: Acute metabolic demands that promote excessive and/or prolonged reactive oxygen species production may stimulate changes in mitochondrial oxidative capacity., Purpose: To assess changes in skeletal muscle H 2 O 2 production, mitochondrial function, and expression of genes at the mRNA and protein levels regulating energy metabolism and mitochondrial dynamics following a hyperinsulinemic-euglycemic clamp in a cohort of 11 healthy premenopausal women., Methods: Skeletal muscle biopsies of the vastus lateralis were taken at baseline and immediately following the conclusion of a hyperinsulinemic-euglycemic clamp. Mitochondrial production of H 2 O 2 was quantified fluorometrically and mitochondrial oxidation supported by pyruvate, malate, and succinate (PMS) or palmitoyl carnitine and malate (PCM) was measured by high-resolution respirometry in permeabilized muscle fiber bundles. mRNA and protein levels were assessed by real time PCR and Western blotting., Results: H 2 O 2 emission increased following the clamp (P<0.05). Coupled respiration (State 3) supported by PMS and the respiratory control ratio (index of mitochondrial coupling) for both PMS and PCM were lower following the clamp (P<0.05). IRS1 mRNA decreased, whereas PGC1α and GLUT4 mRNA increased following the clamp (P≤0.05). PGC1α, IRS1, and phosphorylated AKT protein levels were higher after the clamp compared to baseline (P<0.05)., Conclusions: This study demonstrated that acute hyperinsulinemia induced H 2 O 2 production and a concurrent decrease in coupling of mitochondrial respiration with ATP production in a cohort of healthy premenopausal women. Future studies should determine if this uncoupling ameliorates peripheral oxidative damage, and if this mechanism is impaired in diseases associated with chronic oxidative stress., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Purpose: Cardiometabolic disease remains a leading cause of morbidity and mortality in developed nations. Consequently, identifying and understanding factors associated with underlying pathophysiological processes leading to chronic cardio metabolic conditions is critical. Metabolic health, arterial elasticity, and insulin sensitivity (SI) may impact disease risk, and may be determined in part by myofiber type. Therefore, the purpose of this study was to test the hypothesis that type I myofiber composition would be associated with high SI, greater arterial elasticity, lower blood pressure, and blood lipids; whereas, type IIx myofibers would be associated with lower SI, lower arterial elasticity, higher blood pressure, blood lipids., Methods: Muscle biopsies were performed on the vastus lateralis in 16 subjects (BMI = 27.62 ± 4.71 kg/m 2 , age = 32.24 ± 6.37 years, 43% African American). The distribution of type I, IIa, and IIx myofibers was determined via immunohistochemistry performed on frozen cross-sections. Pearson correlation analyses were performed to assess associations between myofiber composition, SI, arterial elasticity, blood pressure, and blood lipid concentrations., Results: The percentage of type I myofibers positively correlated with SI and negatively correlated with systolic blood pressure SBP, diastolic blood pressure, and mean arterial pressure (MAP); whereas, the percentage of type IIx myofibers were negatively correlated with SI and large artery elasticity, and positively correlated with LDL cholesterol, SBP, and MAP., Conclusions: These data demonstrate a potential link between myofiber composition and cardiometabolic health outcomes in a cohort of premenopausal women. Future research is needed to determine the precise mechanisms in which myofiber composition impacts the pathophysiology of impaired glucose and lipid metabolism, as well as vascular dysfunction.

African American (AA) and European American (EA) women often exhibit differences in hemoglobin (Hb) and 25-hydroxyvitamin D [25(OH)D], both of which can be altered by calorie restriction leading to weight loss. Given these known differences, it is of clinical interest to examine the potential for race-specific, adverse responses to weight loss. Sixty-four overweight (BMI 27-29.9 kg/m 2 ), premenopausal women consumed a standardized, very-low calorie diet to reduce BMI < 25 kg/m2. Ancestry informative markers provided estimates of African admixture, an objective mean of expressing race. Blood sampling and anthropometric measures were performed at baseline and upon meeting target BMI. At baseline, in the overweight state, Hb (g/dL) (AA, 11.7 ± 0.9 vs. EA, 12.5 ± 0.8; p < .01) and 25(OH)D (nmol/L) (AA, 35.7 ± 12.9 vs. EA, 57.0 ± 20.0; p < .01) were lower in AAs. After weight loss, Hb decreased (AA, -0.5 ± 0.7 vs. EA, -0.4 ± 0.6; p = .48) to a similar extent among races. Conversely, 25(OH)D increased (AA, 43.4 ± 14.0 vs. EA 68.2 ± 24.3; p < .01) though the magnitude of change (Δ) was not different (AA, +7.8 ± 13.5 vs. EA, +11.2 ± 16.7; p = .37) between races. Multiple linear regression revealed a positive association between ΔHb and Δ25(OH)D (r = .386; p < .01) adjusted for African admixture, Δtestosterone, and Δbody fat%. Path analyses revealed a significant indirect effect of Δbody fat% on ΔHb through Δ25(OH)D, β =-0.023, CI [-0.06, -0.004]. Following 15% weight loss, participants with the largest increase in serum 25(OH)D exhibited the smallest decrease in Hb. Future research should clarify the optimal degree of calorie restriction to stimulate weight loss while mitigating the potential risk of anemia associated with dieting efforts.

The purpose of this investigation was to examine the associations between circulating markers of inflammation and arterial elasticity in healthy older women. Participants were 50 women older than 60 years of age, body mass index 27 ± 4, and physically untrained. Large artery elasticity, small artery elasticity, systemic vascular resistance, total vascular impedance, estimated cardiac output, and estimated cardiac index were determined using pulse contour analysis. Serum concentrations of tumor necrosis factor-α, C-reactive protein (CRP), and interleukin 6 were assessed. Results from Pearson's correlation revealed that tumor necrosis factor-α was inversely associated with large artery elasticity (-.426, p < .01) and estimated cardiac index (-.324, p < .05) and positively associated with systemic vascular resistance (.386, p < .01) and total vascular impedance (.416, p < .01). Additionally, C-reactive protein was inversely associated with large artery elasticity (-.308, p < .01). The overall implication was that tumor necrosis factor-α and C-reactive protein appear to be critical inflammatory cytokines associated with reductions in arterial elasticity in older women.

Objective: This study compared BMD relative to body weight following a ∼6-month weight loss program and a 1-year weight maintenance phase in premenopausal women and determined whether African American (AA) and European-American (EA) women's BMD respond similarly during weight loss., Design and Methods: Premenopausal women (n = 115, 34 ± 5 years) were evaluated in an overweight state (BMI between 27 and 30 kg/m(2) ), following an 800 kcal/day diet/exercise program designed to reduce BMI<25 kg/m(2) , and 1-year following weight loss., Results: BMD relative to body weight (Z-scores) increased after weight loss, but decreased during the 1-year weight maintenance phase. All 1-year follow-up BMD Z-scores were increased (except L1) compared to baseline measurements (P < 0.05). These sites included the hip neck (+0.088, P = 0.014), total hip (+0.099, P = 0.001), L2 (+0.127, P = 0.013), L3 (+0.135, P = 0.014), and L4 (+0.199, P = 0.002). AAs had significantly higher absolute BMD at all sites (P < 0.05) compared to EAs, but no time by race interactions were evident during weight loss (except in L3)., Conclusion: These results may indicate that weight loss is safe with regard to bone health for overweight premenopausal women., (Copyright © 2013 The Obesity Society.)

Two recent examinations reported a strong association between blood pressure (BP) and resting energy expenditure (REE), independent of body mass and body composition. Both reports postulate that neurohumoral processes that contribute to variation in REE may partly mediate the body mass effect on BP. Therefore, we examined the relationship of REE and BP in 108 asymptomatic women (a) to confirm previous findings in a novel population and (b) to examine the impact of a marker of sympathetic tone on this relationship, as this was indicated as a potentially salient intermediary in previous reports. All testing was performed during a 4-day admission to the General Clinical Research Center. Resting energy expenditure was measured by indirect calorimetry, body composition was determined by dual-energy x-ray absorptiometry, and 24-hour fractionated urinary norepinephrine was determined by high-performance liquid chromatography. Multiple linear regression revealed REE as a significant predictor of systolic BP (β = 0.30, P = .04), independent of race (β = 0. 28, P = .01), age (β = -0.02, P = .80), height (β = -0.38, P = .08), fat mass (β = 0.22, P = .20), fat-free mass (β = 0.08, P = .65), and 24-hour fractionated urinary norepinephrine (β = 0.06, P = .57); and the same model using diastolic BP as the dependent variable approached significance (β = 0.24, P = .09). This study affirms previous findings that REE may be a potential mediator in resting BP, independent of many well-cited factors and, additionally, a marker of sympathetic tone., (Copyright © 2012 Elsevier Inc. All rights reserved.)