Arthur Weltman

• PhD
• Professor (Full) at University of Virginia

Context: Ghrelin circulates in acylated (AG) and deacylated (DAG) forms, which are known to affect appetite. Although acute exercise has been shown to modulate ghrelin levels, data on the impact of exercise intensity on AG and DAG levels and their effects on appetite are sparse and primarily limited to males. Objective: To investigate the effect of...

Curtis, M, Kupperman, N, Westbrook, J, Weltman, AL, Hart, J, and Hertel, J. Neuromuscular performance and the intensity of external training load during the preseason in National Collegiate Athletic Association Division I men's collegiate basketball players. J Strength Cond Res XX(X): 000-000, 2024-The aim of the study was to determine whether acut...

Oral inorganic nitrate (NO 3 ⁻ ) supplementation increases nitric oxide (NO) bioavailability and may improve muscular power in males and females, although data in females is limited. Estrogen increases NO bioavailability and fluctuates throughout the menstrual cycle (MC), with low levels in the early follicular (EF) phase and peaking during the lat...

Inorganic nitrate (NO 3 ⁻ ) supplementation increases nitric oxide (NO) bioavailability and may improve muscular power and endurance, although most studies are in males. Therefore, the present double-blind, randomized, placebo-controlled study examined the effects of NO 3 ⁻ supplementation on isokinetic peak power, maximal voluntary isometric contr...

Ghrelin is a peptide hormone that affects hunger, energy intake, and growth hormone secretion. Ghrelin circulates in two isoforms: acyl ghrelin (AG) and deacylated ghrelin (DAG). Acute exercise is associated with ghrelin suppression, yet most data is in young, trained males and only AG is measured. PURPOSE: To investigate the effects of exercise in...

Dietary nitrate (NO 3 ⁻ ) is a widely used supplement purported to provide beneficial effects during exercise. Most studies to date include predominantly males. Therefore, the present study aimed to investigate if there is a sex-dependent effect of NO 3 ⁻ supplementation on exercise outcomes. We hypothesised that both sexes would exhibit improvemen...

Menopause is associated with reduced nitric oxide bioavailability and vascular function. Although exercise is known to improve vascular function, this is blunted in estrogen-deficient females post-menopause (PM). Here, we examined the effects of acute exercise at differing intensities with and without inorganic nitrate (NO 3 ⁻ ) supplementation on...

Oral inorganic nitrate (NO 3 ⁻ ) supplementation has been shown to increase bioavailable NO and provide potential ergogenic benefits in males, however data in females is scarce. Estrogen increases endogenous NO bioavailability and to fluctuate throughout the menstrual cycle (MC) being lowest in the early follicular phase (EF) and highest during the...

Background Inorganic nitrate (NO3⁻) supplementation is purported to benefit short-term exercise performance, but it is unclear whether NO3⁻ improves longer-term exercise training responses (such as improvements in VO2peak or time to exhaustion (TTE)) versus exercise training alone. The purpose of this systematic review and meta-analysis was to dete...

Objectives To examine the effect of ad-libitum low-glycemic index (GI; high fiber) versus high-GI diet on energy intake, diet quality (Healthy Eating Index 2015 (HEI-2015)), self-reported feelings of hunger and fullness, liking of the foods, and physical activity (PA) in preschoolers. Methods Twenty-five healthy preschoolers (aged 48 ± 7.3 mo, 47%...

Background: Arterial stiffness and endothelial dysfunction are both reported in children with type 1 diabetes (DM1) and may predict future cardiovascular events. In health, nitric-oxide (NO) relaxes arteries and increases microvascular perfusion. The relationships between NO-dependent macro- and microvascular functional responses and arterial stif...

Background Ghrelin is a gut hormone with numerous physiological effects, including the regulation of energy balance, insulin sensitivity, vascular health, and body composition. Acylated (AG) and des-acylated (DAG) ghrelin constitute approximately 22% and 78% of total plasma ghrelin (TG), respectively. Alterations in the TG concentration and the AG/...

Objectives Internal and external factors, including glycemic index (GI), regulate food intake in adults, but little is known about the effect of GI on appetite in children. We examined how low- GI (high fiber) diet changed energy intake, diet quality (Healthy Eating Index 2015 (HEI-2015)), self-reported feelings of hunger, and salivary ghrelin in p...

Background Individuals following anterior cruciate ligament reconstruction demonstrate quadriceps weakness throughout the post-operative recovery and at the time of returning to sport. This is often accompanied with patterns of quadriceps fatigue resistance. As such, fatigue may be an identifier of individuals with delayed recovery. The purpose was...

Objective Examine if adding aerobic exercise to standard medical care (EX+SC) prior to bariatric surgery improves metabolic health in relation to surgical outcomes. Methods Fourteen bariatric patients (age: 42.3±2.5y, BMI: 45.1±2.5 kg/m²) met inclusion criteria and were match-paired to pre-operative SC (n = 7) or EX+SC (n = 7; walking 30min/d, 5d/...

Purpose: This prospective trial's objective was to determine feasibility and outcomes of an exercise-based intervention for rural overweight/obese female cancer survivors. Materials and methods: Survivors of endometrial, breast, or ovarian cancer enrolled in a 6-month program of increased aerobic activity (30 minutes daily walking) and strength-...

Objective Examine the effect of aerobic exercise (EX) combined with standard medical care (SC) (EX + SC) compared to SC alone on cardiometabolic health and quality of life in relation to surgical outcomes. Methods Patients receiving bariatric surgery were match-paired to 30 days of pre-operative SC (n = 7, 1 male, 39.0 ± 5.3 years, body mass index...

Background: Sleep dysfunction is common and disabling in persons with Parkinson's Disease (PD). Exercise improves motor symptoms and subjective sleep quality in PD, but there are no published studies evaluating the impact of exercise on objective sleep outcomes. The goal of this study was to to determine if high-intensity exercise rehabilitation c...

Introduction: The impact of interval (INT) vs. continuous (CONT) exercise training on endothelial function in relation to glucose metabolism prior to clinically meaningful weight loss is unknown in adults with prediabetes. Methods: Twenty-six subjects with prediabetes (60 ± 1 y; 33 ± 1 kg/m2; 2-hr-PG OGTT: 145 ± 7 mg/dl) were randomized to 60 mi...

Prediabetes is associated with impaired oxidative capacity and altered substrate utilization during exercise. The effects of continuous (CONT) versus interval (INT) exercise training on fat oxidation during an acute exercise bout at the same absolute and relative intensities are unknown in this population. Obese females/males (n = 17, n = 5) with p...

The consumption of fiber-rich foods may negate the deleterious effects of high-fat meals on postprandial triglyceridemia and endothelial function. Despite supportive data in adults, little is known about the effects of high-fat and high-fiber foods on cardiovascular health parameters in pediatric populations. In this crossover trial, male and femal...

Background: Osteoarthritis after anterior cruciate ligament reconstruction has been linked with changes in gait. Individuals with reconstruction demonstrate gait changes after exercise, however there is no information on altered gait after exercise based on sex. The purpose of this study was to examine the association of sex on changes in running...

Background: Extracellular vesicles (EVs) are purported to mediate type 2 diabetes (T2D) and cardiovascular disease (CVD) risk and development. Physical activity and a balanced diet reduce disease risk, but no study has tested the hypothesis that short-term interval (INT) training would reduce EVs compared with continuous (CONT) exercise in adults...

In today’s research environment, children’s diet, physical activity, and other lifestyle factors are commonly studied in the context of health, independent of their effect on cognition and learning. Moreover, there is little overlap between the two literatures, although it is reasonable to expect that the lifestyle factors explored in the health-fo...

Although extracellular vesicles (EVs) are a novel biomediator of type 2 diabetes (T2D) and cardiovascular disease (CVD), the effects of hyperglycemia on EVs in humans is unknown. We tested the hypothesis that a 75-g oral glucose tolerance test (OGTT) would promote changes in EVs in relation to CVD risk. Twenty-five obese adults (Age: 52.4 ± 3.2 yea...

The objective of this study was to test if a low-calorie diet plus interval exercise (LCD+INT) improves adiposopathy, an endocrine dysfunction, when compared with an energy-deficit–matched LCD in obese women. Subjects (age: 48.2 ± 2.4 years, body mass index: 37.8 ± 1.3 kg/m²) were randomized to a 13-day LCD (n = 12; mixed meals of ∼1200 kcal/day) o...

No short-term exercise data exist testing whether training intensity modifies hormonal and perceived appetite in obese adults with prediabetes. Therefore, we compared the effects of short-term moderate-continuous (CONT) vs. high-intensity interval (INT) training on appetite regulation. Twenty-eight obese adults [age: 61.3 ± 1.5 yr; body mass index...

New findings: What is the central question of this study? We compared high-intensity interval versus continuous training on fasting and postprandial arterial stiffness in people with prediabetes. What is the main finding and its importance? We show, for the first time, that exercise improves the augmentation index during the postprandial state, bu...

Background Understanding factors that influence physical activity (PA) and sedentary behavior is crucial to develop interventions to improve adolescents’ health-related behaviors. Purpose To compare the influence of friends and psychosocial factors on moderate-to-vigorous physical activity (MVPA) and screen time (ST) between normal weight (NW) and...

Purpose: The optimal short-term exercise dose to improve glucose tolerance in relation to metabolic flexibility and/or insulin resistance is unknown. Therefore, we tested if short-term, work-matched continuous (CONT) versus interval (INT) exercise training improves glucose tolerance in part by reducing insulin resistance and increasing metabolic f...

Low cardiorespiratory fitness (CRF) is associated with cardiovascular disease (CVD) independent of obesity. Extracellular vesicles (EVs) are a novel target of CVD, however, it remains unknown if obese individuals with very poor fitness (VPF) have elevated EVs versus people with poor fitness (PF). Thus, we tested whether VPF was associated with grea...

Microparticles (MPs) are a novel mediator and/or biomarker of cardiovascular disease (CVD) and type 2 diabetes. A high fat meal can elevate MP release in relation to CVD risk, but the effects of carbohydrates are unknown. This is clinically relevant as low-fat diets are advised for glycemic control. We tested the hypothesis that a 75g oral glucose...

Hyperglycemia promotes vascular complications through, in part, an inflammatory-mediated impairment in endothelial function. However, the effects of interval (INT) vs. continuous (CONT) training on endothelial function prior to clinically meaningful weight loss is unknown in adults with prediabetes. Twenty-six subjects with prediabetes (60±1y; 33±1...

Few data exist that assess athlete tracking and monitoring for the development of strategies to optimize performance and reduce fatigue in elite athletes. The purpose of the present study was to assess the efficacy of external load and internal stress monitoring as assessment tools for examining a performance index of fatigue. A retrospective analy...

Performance in soccer has been characterized previously using time-motion analyses; however, it is unclear if men’s college soccer shares performance characteristics with women’s college or men’s professional soccer. The purpose of this study was to compare proportions of matches spent walking, jogging, running, and sprinting in men’s college socce...

Exercise is a cornerstone therapy for chronic diseases related to multiorgan insulin resistance. However, not all individuals show the anticipated improvement in insulin sensitivity following exercise and these individuals are considered exercise resistant. Caloric restriction is an approach to enhance the effect of exercise on increasing periphera...

Bariatric surgery is an effective and durable treatment for individuals with obesity and its associated comorbidities. However, not all patients meet weight loss and/or cardiometabolic goals following bariatric surgery, suggesting that some people are bariatric surgery resistant. The reason for this resistance is unclear, but potential factors, suc...

Lower extremity injuries are most common in more active and fit individuals, suggesting that adaptations from neuromuscular fatigue may differ depending on type of exercise and fitness level. The purpose of this study was to compare changes in gait in highly fit and recreationally active individuals before and after two exercise protocols. Lower ex...

Stine, KA, Moxey, JR, Gilbertson, NM, Malin, SK, and Weltman, AL. Effects of feedback type and personality on 2,000-m ergometer performance in female varsity collegiate rowers. J Strength Cond Res 33(8): 2170-2176, 2019-Rowing performance is routinely tested on ergometers, involving visual cues and verbal encouragement, whereas on-water rowing lack...

Time of day is a key factor that influences the optimization of athletic performance. Intercollegiate coaches oftentimes hold early morning strength training sessions for a variety of factors including convenience. However, few studies have specifically investigated the effect of early morning vs. late afternoon strength training on performance ind...

Background: Sedentary behavior (SB) increases throughout adolescence, and is associated with adverse health outcomes. Purpose: Examine psychosocial and friend influences on SB and screen time in adolescents using a mixed-methods design. Methods: 108 middle and high school students wore accelerometers to measure objective SB, completed screen t...

We compared the effects of traditional (stable) and non-traditional (dynamic) school furniture on children's physical activity (PA), energy expenditure (EE), information retention, and math skills. Participants were 12 students (8.3 years, 58 % boys) in grades 1-5. Participants wore an Actigraph GT3X+ accelerometer (to assess PA), and an Oxycon Mob...

Objective: The decline in insulin sensitivity (SI) associated with puberty increases the difficulty of achieving glycemic control in adolescents with type 1 diabetes (T1D). The aim of this study was to determine whether glutamine supplementation affects blood glucose by enhancing SI in adolescents with T1D. Methods: Thirteen adolescents with T1D...

(1) Determine the association between adolescent moderate-to-vigorous physical activity (MVPA) and screen time with their nominated friends' behaviors and (2) explore potential mechanisms of friends' social influences on MVPA and screen time. Participants consisted of 152 adolescents (mean age: 14.5 years, 53 % female, 50 % high school, 80 % Caucas...

Objective: To determine whether high intensity exercise (HIE) would improve endothelial function more than an isocaloric bout of moderate intensity exercise (MIE) following glucose ingestion in adults with prediabetes. Methods: Twelve subjects with prediabetes completed all three conditions: time-course matched control and isocaloric exercise (∼...

Little is known about the effects of exercise intensity on compensatory changes in glucose-stimulated insulin secretion (GSIS) when adjusted for adipose, liver and skeletal muscle insulin resistance (IR). Fifteen participants (8F, Age: 49.9±3.6yr; BMI: 31.0±1.5kg/m2; VO2peak: 23.2±1.2mg/kg/min) with prediabetes (ADA criteria, 75g OGTT and/or HbA1c)...

Data for β-cell function across conditions. (PDF)

Data for plasma glucose, insulin, C-peptide and FFA across conditions. (PDF)

Data for glucose-stimulated insulin secretion across conditions. (PDF)

Data for insulin resistance across conditions. (PDF)

Prediabetes is a heterogeneous term that encompasses different origins of insulin resistance and insulin secretion that contribute to distinct patterns of hyperglycemia. In fact, prediabetes is an umbrella term that characterizes individuals at high risk for developing type 2 diabetes (T2D) and/or cardiovascular disease (CVD). Based on current defi...

In perceiving spatial layout, the angular units of visual information are transformed into linear units appropriate for specifying size and extent. This derivation of linear units from angular ones requires geometry and a ruler. Numerous studies suggest that the requisite perceptual rulers are derived from the observer's body. In the case of walkab...

To establish whether changes to indices of insulin sensitivity (Si) derived from fasting and oral glucose tolerance tests (OGTT) are comparable to Si determined by the oral minimal model (OMM) in response to acute moderate- (MIE) and high intensity exercise (HIE). Eighteen prediabetic subjects completed 3 conditions: Control (no-exercise), and ∼200...

Context: Return to activity in the presence of quadriceps dysfunction may predispose individuals with anterior cruciate ligament reconstruction (ACLR) to long-term joint degeneration. Asymmetry may manifest during movement and result in altered knee-joint-loading patterns; however, the underlying neurophysiologic mechanisms remain unclear. Object...

Context Normal, symmetrical quadriceps strength is a common clinical goal after anterior cruciate ligament reconstruction (ACLR). Currently, the clinical thresholds for acceptable unilateral quadriceps function and symmetry associated with positive outcomes after return to activity are unclear. Objective To establish quadriceps-activation and knee...

This study’s aim was to assess the histological and metabolic effects of N-3 polyunsaturated fatty acids (PUFA) versus placebo while adjusting for the impact of age and weight change in NASH patients. (ClinicalTrials.gov: NCT00681408). Methods Forty-one subjects with non-cirrhotic NASH were enrolled, and 34 completed the study. 17 received N-3 fis...

To determine the role of endogenous opioid peptides in regulating pulsatile luteinizing hormone (LH) release in the early follicular phase of the menstrual cycle of eumenorrheic women, we evaluated serum LH concentrations in blood collected every 10 min for 12 h in 27 women each studied during two menstrual cycles: (1) without pretreatment and (2)...

Background We examined the effects of a proprietary herbal/botanical supplement (StemSport, Stemtech, San Clemente, CA.) suggested to increase circulating stem cells, decrease inflammation, and attenuate exercise induced muscle damage on recovery from delayed onset muscle soreness (DOMS). Methods Sixteen subjects (male = 7, female = 9; age 23.8 ±...

Background StemSport (SS; StemTech International, Inc. San Clemente, CA) contains a proprietary blend of the botanical Aphanizomenon flos-aquae and several herbal antioxidant and anti-inflammatory substances. SS has been purported to accelerate tissue repair and restore muscle function following resistance exercise. Here, we examine the effects of...