Environmental exposure to wildfire smoke may reduce microvascular oxygenation during graded handgrip exercise: A case series.

Wildfire smoke (WFS) is an urgent and rapidly growing threat to global health. Aside from obvious threats to pulmonary function, increases in cardiac abnormalities or myocardial infarction have been documented during WF season, but little is known about the effects of WFS on cardiovascular health. We investigated the effect of nonoccupational WFS exposure on cardiovascular and pulmonary function at rest and during graded handgrip exercise through a case series of young, healthy adults (n = 4, 25 ± 6 years) assessed after ≥3 days of bad or good air quality. Peripheral and estimated central blood pressures, vascular stiffness, and microvascular function (Near infrared spectroscopy, NIRS) were assessed at rest, and during rhythmic handgrip exercise. WFS did not appear to alter resting peripheral, central BP, or vascular stiffness (all, p > 0.05). Slope 1 and slope 2 from the NIRS-vascular occlusion test (NIRS-VOT) were not different between conditions (p > 0.05). The change in SmO2 during exercise was lower (p = 0.02, η p 2 $$ {\eta}_{\mathrm{p}}^2 $$ = 0.62) with bad air quality. These preliminary findings suggest modest effects of environmental WFS exposure on muscle microvascular function during exercise in healthy adults. Future work is needed to elucidate the physiological changes with WFS exposure and the increased risk of cardiovascular events, perhaps exacerbated through physical activity.

Central and peripheral haemodynamics at exercise onset: the role of central command.

PURPOSE: The involvement of central command in central hemodynamic regulation during exercise is relatively well-known, although its contribution to peripheral hemodynamics at the onset of low-intensity contractions is debated. This study sought to examine central and peripheral hemodynamics during electrically-evoked muscle contractions (without central command) and voluntary muscle activity (with central command). METHODS: Cyclic quadriceps isometric contractions (1 every second), either electrically-evoked (ES; 200 ms trains composed of 20 square waves) or performed voluntarily (VC), were executed by 10 healthy males (26 ± 3 years). In both trials, matched for force output, peripheral and central hemodynamics were analysed. RESULTS: At exercise onset, both ES and VC exhibited equal peaks of femoral blood flow (1276 ± 849 vs. 1117 ± 632 ml/min, p > 0.05) and vascular conductance (15 ± 11 vs. 13 ± 7 ml/min/mmHg, p > 0.05), respectively. Similar peaks of heart rate (86 ± 16 bpm vs. 85 ± 16 bpm), stroke volume (100 ± 20 vs. 99 ± 27 ml), cardiac output (8.2 ± 2.5 vs. 8.5 ± 2.1 L/min), and mean arterial pressure (113 ± 13 vs. 113 ± 3 mmHg), were recorded (all, p > 0.05). After ~ 50 s, all the variables drifted to lower values. Collectively, the hemodynamics showed equal responses. CONCLUSION: These results suggest a similar pathway for the initial (first 40 s) increase in central and peripheral hemodynamics. The parallel responses may suggest an initial minimal central command involvement during the onset of low-intensity contractions, likely associated with a neural drive activation delay or threshold.

Limb, sex, but not acute dietary capsaicin, modulate the near-infrared spectroscopy-vascular occlusion test estimate of muscle metabolism.

The downward slope during the near-infrared spectroscopy (NIRS)-vascular occlusion test (NIRS-VOT) is purported as a simplified estimate of metabolism. Whether or not the NIRS-VOT exhibits sex- or limb-specificity or may be acutely altered remains to be elucidated. Thus, we investigated if there is limb- or sex specificity in tissue desaturation rates (DeO2) during a NIRS-VOT, and if acute dietary capsaicin may alter this estimate of muscle metabolism. Young healthy men (n = 25, 21 ± 4 years) and women (n = 20, 20 ± 1 years) ingested either placebo or capsaicin, in a counterbalanced, single-blind, crossover design after which a simplified NIRS-VOT was conducted to determine the DeO2 (%/s), as an estimate of oxidative muscle metabolism, in both the forearm (flexors) and thigh (vastus lateralis). There was a significant limb effect with the quadriceps having a greater DeO2 than the forearm (-2.31 ± 1.34 vs. -1.78 ± 1.22%/s, p = 0.007, ηp 2 = 0.19). There was a significant effect of sex on DeO2 (p = 0.005, ηp 2 = 0.203) with men exhibiting a lesser DeO2 than women (-1.73 ± 1.03 vs. -2.36 ± 1.32%/s, respectively). This manifested in significant interactions of limb*capsaicin (p = 0.001, ηp 2 = 0.26) as well as limb*capsaicin*sex on DeO2 (p = 0.013, ηp 2 = 0.16) being observed. Capsaicin does not clearly alter O2-dependent muscle metabolism, but there was apparent limb and sex specificity, interacting with capsaicin in this NIRS-derived assessment.

Exploring the Bob Ross effect: A psychophysiological investigation.

Watching news broadcasts is known to elicit psychological stress. Conversely, the iconic painter Bob Ross (BR) has risen to pop culture status and amassed a following, as many find the messages and sounds of BR to be soothing and relaxing. Though, it has yet to be directly tested if such exposure can confer psychological or physiological benefit. The purpose of this study was to compare the effects of watching BR versus streaming news on markers of cardiovascular health and profile of mood states (POMS). It was hypothesized that watching BR would increase POMS scores and heart rate variability (HRV). It was also hypothesized that watching the news would increase blood pressure (BP), vascular stiffness (VS), and heart rate (HR). METHODS: In a randomized, controlled, crossover design, 18 young (21 ± 1 yrs, 9 female, 9 male) healthy participants (172.6 ± 9.9 cm, 69 ± 18 kg) were assessed for BP, VS, HR, HRV, and POMS before and after watching an episode of BR or the News matched for time (∼27 mins). RESULTS: A significant interaction effect on POMS scores were observed for, anxiety (p = 0.01), anger (p = 0.008), depression (p = 0.003), fatigue (p = 0.001), and confusion (p = 0.01) domains after watching BR. The LF/HF ratio, an HRV marker of sympathovagal balance, was significantly lower after watching BR (p = 0.04). There were no significant time, condition, or interaction effects on systolic BP, mean arterial pressure, and diastolic BP. CONCLUSION: The "Bob Ross Effect" reduces overall mood disturbance, though appears to exert little influence on the cardiovascular system in this acute paradigm.

The Impact of COVID-19 Health and Safety Measures on the Self-Reported Exercise Behaviors and Mental Health of College Students.

The public-health restrictions (e.g., remote learning, restricted access to facilities and dining halls) put in place by colleges to reduce the spread of COVID-19 resulted in forced isolation and modifications to health-related behaviors. The restrictions and uncertainty associated with COVID-19 may have exacerbated the challenges of meeting exercise recommendations and mental-health concerns. The purpose of this study was to assess the impact of restrictions on students' exercise habits and their levels of anxiety, stress, and depression. Five-hundred and forty students completed a 29-question survey on individual demographics, living arrangements, exercise, sleep, diet, and mental health. Significant changes in weekly days of exercise and intensity were reported. Increases in anxiety, stress, and depression were reported. The two most frequently reported changes in exercise behavior were an increase in minutes of aerobic training (5%) and a combination of reduced minutes of aerobic and resistance training (3.9%), which could be reflective of an individual's ability and/or desire to maintain exercise behavior during the restrictions. Alternatively, for those students who reduced their exercise habits, aerobic training (11%) was the mode that suffered the most. Demographic factors such as ethnicity, regional residence, and gender were found to have significant effects on stress, anxiety, and depression. Amidst pandemics and future health emergencies, colleges should prioritize establishing opportunities for students to exercise, helping them meet physical activity recommendations and combat mental-health issues.

An Analysis of the Impact of Religious Affiliation and Strength of Religiosity on Sexual Health Practices of Sexually Active Female College Students.

Despite great strides in the development of contraceptive technologies, the United States has one of the highest teen pregnancy rates in the world. Religion and associated values may shape the sexual health behaviors of college students, as prior studies have aimed to determine how social factors may influence the use of contraception amongst college students. Thus, we sought to examine the differences in current contraceptive methods and the age of first contraceptive usage among sexually active female college students with different religious affiliations and strengths of religiosity. It was hypothesized that there would be no difference in current contraceptive methods among different religious affiliations and strengths of religions and that there would be a difference in the age of first contraceptive usage among different religious affiliations and strengths of religiosity. Two hundred and twenty-four college-aged females completed a 20-question survey about sexual health and religious practices. Chi-squared tests were implemented to determine the frequencies of responses across religious affiliations and strengths of religiosity. Significant differences in the frequency of responses for the age of first contraceptive usage were observed across different strengths of religiosity (p = 0.016) and for the self-perceived impact of religion on sexual health across different religious affiliations (p = 0.033) and strengths of religiosity (p = 0.005). All other differences were found not to be statistically significant. It was determined that increased strengths of religiosity resulted in delayed onset of contraceptive usage and that both different religious affiliations and greater strengths of religiosity lead to different self-perceived impacts of religion on sexual health despite low levels of current practice.

The effects of short-term caloric restriction on cardiometabolic health in overweight/obese men and women: A single-arm trial.

Overweight and obesity (Ow/Ob) is a risk factor for cardiometabolic disease. Caloric restriction (CR) have been investigated but little is known about the acute effects of CR and often such diets are not standardized. Thus, we aimed to assess the impact of a new standardized 3-day CR diet (590 kcal/d intake) on cardiometabolic health in weight-stable Ow/Ob individuals. In a single-arm design, 15 Ow/Ob men and women were assessed pre-post a 3-day standardized CR diet; specifically, body weight/composition (%body fat, visceral fat score (Vfs), blood pressure (BP), and vascular stiffness (VS), resting energy expenditure (REE), substrate utilization (respiratory quotient, RQ), and blood glucose/lipid profile). CR lowered body weight (93.1 ± 15.2 to 90.67 ± 14.4 kg, p < 0.001, d = 1.9), %fat (37.2 ± 7.5 to 35.8 ± 7.5%, p = 0.002, d = 1.1), and Vfs (13.1 ± 4.5 to 12.2 ± 3.9 a.u., p = 0.002, d = 1.1), but not body water (46.3 ± 3.6 to 46.0 ± 3.6%, p = 0.29). CR lowered VS (29.8 ± 17.5 to 21.5 ± 14.5%, p = 0.05, d = 0.6), but not BP (p > 0.05). Blood glucose (86 ± 7 to 84 ± 11 mg/dL, p = 0.33) and lipids (total cholesterol (196 ± 49 to 203 ± 54 mg/dL, p = 0.16) and TC/HDL (4.9 ± 2.4 to 6.1 ± 4.7, p = 0.13)) were unchanged. RQ decreased with CR (0.84 ± 0.01 to 0.76 ± 0.00, p < 0.001, d = 1.9), though REE was unchanged (p = 0.83). The 3-day CR diet significantly improved fat metabolism, body weight and composition, and vascular stiffness.

Heart rate variability of elite female rowers in preparation for and during the national selection regattas: a pilot study on the relation to on water performance.

Elite athletes require a delicate balance of physiological and psychological stress and recovery-essential for achieving optimal performance. Monitoring heart rate variability (HRV) provides a non-invasive estimation of both physiological and psychological stress levels, offering potentially valuable insights into health, performance, and adaptability. Previous studies, primarily conducted on male participants, have shown an association between HRV and performance in the context of rowing training. However, given the rigorous nature of rowing training, it is crucial to investigate HRV in elite rowers, particularly during the U.S. national selection regattas (NSR). Purpose: To comprehensively analyze elite female rowers, evaluating acute changes in HRV and subjective psychometrics during the NSR. Methods: Five elite female rowers (26 ± 2 years, 180 ± 8 cm, 82 ± 8 kg, 19 ± 6%fat) were recruited and tracked prior to and during NSR I and II. Morning HRV measures were completed using photoplethysmography (HRV4training) along with self-reported levels of fatigue, soreness, rating of perceived exertion, mentally energy and physical condition. Results: Significant decreases were observed in log transformed root-mean square of successive differences (LnRMSSD; p = 0.0014) and fatigue (p = 0.01) from pre-to-during NSR, while mental energy (p = 0.01), physical condition (p = 0.01), and motivation (p = 0.006) significantly increased. These psychometric measures returned to pre-NSR levels, at post-NSR (all p < 0.05), though HRV remained slightly suppressed. NSR on-water performance was not correlated to LnRMSSD or the change in LnRMSSD (p > 0.05). Discussion: HRV and psychometric measures are sensitive to the stress of elite rowing competition in females. However, HRV was not associated with on-water rowing performance during an elite rowing competition.

Impact of high intensity interval exercise with and without heat stress on cardiovascular and aerobic performance: a pilot study.

BACKGROUND: Heat stress during aerobic exercise training may offer an additional stimulus to improve cardiovascular function and performance in a cool-temperate environment. However, there is a paucity of information on the additive effects of high-intensity interval exercise (HIIE) and acute heat stress. We aimed to determine the effects of HIIE in combination with acute heat stress on cardiovascular function and exercise performance. METHODS: Twelve active (peak O2 consumption [VO2peak]: 47 ± 8 ml·O2/min/kg) young adults were counterbalanced to six sessions of HIIE in hot (HIIE-H, 30 ± 1 °C, 50 ± 5% relative humidity [RH]) or temperate conditions (HIIE-T, 20 ± 2 °C, 15 ± 10% RH). Resting heart rate (HR), HR variability (HRV), central (cBP) and peripheral blood pressure (pBP), peripheral mean arterial pressure (pMAP), pulse wave velocity (PWV), VO2peak, and 5-km treadmill time-trial were measured pre- and post-training. RESULTS: Resting HR and HRV were not significantly different between groups. However, expressed as percent change from baseline, cSBP (HIIE-T: + 0.9 ± 3.6 and HIIE-H: -6.6 ± 3.0%, p = 0.03) and pSBP (HIIE-T: -2.0 ± 4.6 and HIIE-H: -8.4 ± 4.7%, p = 0.04) were lower in the heat group. Post-training PWV was also significantly lower in the heat group (HIIE-T: + 0.4% and HIIE-H: -6.3%, p = 0.03). Time-trial performance improved with training when data from both groups were pooled, and estimated VO2peak was not significantly different between groups (HIIE-T: 0.7% and HIIE-H: 6.0%, p = 0.10, Cohen's d = 1.4). CONCLUSIONS: The addition of acute heat stress to HIIE elicited additive adaptations in only cardiovascular function compared to HIIE alone in active young adults in temperate conditions, thus providing evidence for its effectiveness as a strategy to amplify exercise-induced cardiovascular adaptations.

Sex differences in estimates of cardiac autonomic function using heart rate variability: effects of dietary capsaicin.

PURPOSE: Heart rate variability (HRV) estimates the autonomic nervous system (ANS) influence on the heart and appears sex-specific. Sensory afferents exhibit sex-specificity; although, it is unknown if Capsaicin, an agonist for transient receptor potential vanilloid channel-1 (TRPV1), alters cardiac ANS activity in a sex-dependent manner, which could be important given the predictive nature of HRV on risk of developing hypertension. Thus, we explored if there was sex-specificity in the effect of capsaicin on estimated cardiac ANS activity. METHODS: HRV was measured in 38 young males (M: n = 25) and females (F: n = 13), in a blinded-crossover design, after acute ingestion of placebo or capsaicin. Resting HR, RR-interval, root-mean-square of successive differences (RMSSD), natural log-transformed RMSSD (LnRMSSD), standard deviation of n-n intervals (SDNN), number of pairs of successive n-n intervals differing by > 50 ms (NN50), and percent NN50 (PNN50) were obtained using standard techniques. RESULTS: Significant sex differences were observed in mean HR (M: 59 ± 9.3 vs. F: 65 ± 12 beats/min, p = 0.036, η2 = 0.098), minimum HR (M: 47 ± 8.3 vs. F: 56 ± 12 beats/min, p = 0.014, η2 = 0.124), and NN50 (M: 177 ± 143 vs. F: 29 ± 17, p < 0.001, η2 = 0.249). There was a significant interaction of sex*treatment (p = 0.02, η2 = 0.027) for RMSSD, where males increased (78 ± 55 vs. 91 ± 64 ms), and females decreased (105 ± 83 vs. 76 ± 43 ms), placebo vs. capsaicin. CONCLUSION: This controlled study recapitulates sex differences in HR and HRV, but revealed a sexual dimorphism in the parasympathetic response to capsaicin, perhaps due to differing TRPV1-afferent sensitivity, highlighting a potential mechanism for differential regulation of hemodynamics, and CVD risk, and should be considered in future studies.

Intermittent fasting and protein pacing are superior to caloric restriction for weight and visceral fat loss.

OBJECTIVE: This study compared intermittent fasting and protein pacing (IF-P) versus a heart-healthy caloric restriction (CR) diet, matched for energy intake and physical activity energy expenditure, on body weight, total and visceral fat mass, and cardiometabolic health outcomes in adults with obesity. METHODS: IF-P (n = 21) and CR (n = 20) were assessed pre- (week 0), mid- (week 5), and post- (week 9) intervention. RESULTS: Both groups reduced (p < 0.05) weight, total and visceral fat mass, blood pressure and lipids, and desire to eat food and increased proportion of fat-free mass. IF-P resulted in greater (p < 0.05) reductions in weight (-9% vs. -5%), total (-16% vs. -9%) and visceral (-33% vs. -14%) fat mass, and desire to eat (-17% vs. 1%) and increased fat-free mass percent (6% vs. 3%) compared with CR. These improvements were despite similar weekly total energy intake (IF-P, 9470 ± 550 vs. CR, 9095 ± 608 kcal/wk; p = 0.90) and physical activity energy expenditure (IF-P, 300 ± 150 vs. CR, 350 ± 200 kcal/d; p = 0.79). CONCLUSIONS: IF-P and CR optimize weight loss, body composition, cardiometabolic health, and hunger management, with IF-P providing greater benefits.

Does sex influence near-infrared spectroscopy-derived indicators of microvascular reactivity and the response to acute dietary capsaicin.

Endothelial dysfunction is associated with cardiovascular disease development, nitric oxide (NO) deficiencies, and may be limb or sex-specific. Prior in vitro work indicated that the transient receptor potential vanilloid channel-1 (TRPV1) is expressed in human arteries and the TRPV1 agonist capsaicin alters vasodilation in an endothelium-dependent manner; however, it is unknown if this translates in vivo or is limb or sex-dependent. Therefore, we sought to determine if there was limb or sex-specificity in the effect of capsaicin on microvascular function using near-infrared spectroscopy (NIRS)-derived tissue oxygen saturation (StO2) reperfusion slope. In a blinded placebo-controlled crossover design, 45 young males (M: n = 25) and females (F: n = 20), the reperfusion slopes of the forearm and quadriceps were assessed, and a urine sample obtained to assay for nitrate/nitrite (NOx) concentrations and antioxidant capacity after acutely ingesting placebo or capsaicin. Under placebo, females had greater reperfusion rates in both the forearm (M: 0.44 ± 0.24 vs. F: 0.98 ± 0.46 %/sec; p = 0.002, d = -1.50) and quadricep (M: 0.86 ± 0.31 vs. F: 1.17 ± 0.43 %/sec; p = 0.010, d = -0.85). Capsaicin decreased microvascular responsiveness in the forearm of females (placebo: 0.98 ± 0.45 vs. capsaicin: 0.84 ± 0.45 %/sec) as compared to males (placebo: 0.45 ± 0.24 vs. capsaicin: 0.38 ± 0.16 %/sec, interaction p < 0.001, η2 = 0.475). There was a sex*treatment interaction for NOx concentrations, where males increased (placebo: 21.13 ± 12.83 vs. capsaicin: 23.82 ± 13.34 µM), while females decreased (placebo: 22.78 ± 14.40 vs. capsaicin: 14.43 ± 10.01 µM; p = 0.037, η2 = 0.042). Using NIRS to assess microvascular function, there is apparent limb and sex-specificity, and, for the first-time, document that acute oral capsaicin alters reperfusion slope in a sexually divergent manner.

The Effects of Accessory Blood Flow Restriction Training on Muscle Size and Strength in Division III Soccer Athletes: A Preliminary Ecological Study.

Blood flow restriction training (BFRT) uses occlusion during low-intensity resistance training (< 50% of 1-repetition maximum, 1RM) to reduce arterial blood flow and venous return, imposing greater metabolic stress but similar muscular hypertrophy and strength gains as high-intensity resistance training (HIRT). However, no study, to date, has incorporated BFRT in a collegiate strength and conditioning setting to assess ecological validity. We aimed to investigate the effects of adding 6-weeks of accessory BFRT or HIRT to NCAA Division III soccer players prescribed resistance training regimen on muscle strength and size. Male and female (n = 17) athletes were randomly assigned to complete biceps curls 2x/week under BFRT or control (HIRT), following regularly scheduled strength training. Bicep strength (1RM) and circumference (BC) were assessed at weeks 0, 3, and 6 (men only). In men, for BC no significant interaction of condition x time was observed (p = 0.861), though condition (BFRT vs Control, p = 0.025) and time (p = 0.024) were significant. For 1RM, there was no significant interaction of condition x time (BFRT vs HIRT, p = 0.067) or of condition (p = 0.598), but there was a significant effect of time (p = 0.004). In women, there was no significant interaction between time and condition (p = 0.765) or of condition (p = 0.971) on BC, but time was significant (p = 0.045). For 1RM, there was no significant interaction of condition x time (p = 0.227) or of condition (p = 0.741), but time was (p = 0.018). In this preliminary ecological study, BFRT induced similar increases in muscle strength and circumference as HIRT in soccer players, suggesting that BFRT could be incorporated into collegiate athlete training.

Physiological Responses to Speed-Matched Running on Non-Motorized Assault AirRunner versus Traditional Treadmills in Active Females: A Pilot Study.

Treadmills are utilized as a training tool to improve aerobic fitness, but precise understanding of intensity and the corresponding physiological strain is critical for optimizing exercise prescription and associated adaptations. Running on non-motorized, curved treadmills may result in greater oxygen uptake (VO2), increased heart rate (HR), and increased rating of perceived exertion (RPE) compared to traditional motorized treadmills. The purpose of this study was to investigate the physiological responses on non-motorized versus traditional motorized treadmills during speed-matched running. Participants were 4 college-aged, recreationally active females. HR, VO2, respiratory exchange ratio (RER), and RPE were monitored during 3 speed-matched stages of incremental exercise in two conditions: the non-motorized Assault AirRunner and a traditional motorized treadmill, as well as for 5 minutes post-exercise. VO2, RER, and HR were greater in the Assault condition (ESVO2 = 0.998, ESRER = 0.839, ESHR = 0.972, p < 0.05). While not significant between groups, RPE showed a greater increase with increasing speeds in the Assault condition (ES = 0.728), as did RER (ES = 0.800, p < 0.05). Cumulative excess-post exercise oxygen consumption (EPOC) during a five-minute period post-exercise was also greater in the Assault condition, and HR and RER remained higher five minutes post-exercise in the Assault condition (ESEPOC = 0.738, ESHR = 1.600, ESRER = 2.075, p < 0.05). The Assault AirRunner elicited greater physiological responses (VO2, carbohydrate usage, and HR) in response to speed-matched running in comparison to a traditional motorized treadmill in active college-aged females. Collectively, aerobic exercise conducted on the Assault AirRunner has a greater physiological and perceived intensity and need to be taken into consideration when designing and implementing training programs or testing.

Life without Proteinase Activated Receptor 2 (PAR2) Alters Body Composition and Glucose Tolerance in Mice.

The potential role of proteinase activated receptor 2 (PAR2) in the development of age-related obesity and insulin resistance is not well-understood. To address the hypothesis that deletion of PAR2 might ameliorate age-related obesity and impaired glucose homeostasis, we assessed body composition and insulin action in 18-month-old male PAR2 knockout (PAR2KO-AG), age-matched (AG) and young C57BL6 (YG, 6-month-old) mice. Body composition was measured by magnetic resonance spectroscopy (MRS) and insulin action was assessed by glucose tolerance (GT), insulin tolerance (IT) and AICAR tolerance (AT) testing. AG mice weighed significantly more than YG mice (p = 0.0001) demonstrating age-related obesity. However, PAR2KO-AG mice weighed significantly more than AG mice (p = 0.042), indicating that PAR2 may prevent a portion of age-related obesity. PAR2KO-AG and AG mice had greater fat mass and body fat percentage than YG mice. Similar to body weight, fat mass was greater in PAR2KO-AG mice compared to AG mice (p = 0.045); however, only a trend for greater body fat percentage in PAR2KO-AG compared to AG mice was observed (p = 0.09). No differences existed in lean body mass among the PAR2KO-AG, AG, and YG mice (p = 0.58). With regard to insulin action, the area under the curve (AUC) for GT was lower in PAR2KO-AG compared to AG mice (p = 0.0003) and YG mice (p = 0.001); however, no differences existed for the AUC for IT or AT. Our findings indicate that age-related obesity is not dependent on PAR2 expression.

Intermittent fasting two days versus one day per week, matched for total energy intake and expenditure, increases weight loss in overweight/obese men and women.

BACKGROUND: Intermittent fasting (IF), consisting of either a one-day (IF1) or two consecutive days (IF2) per week, is commonly used for optimal body weight loss. Our laboratory has previously shown an IF1 diet combined with 6d/week of protein pacing (P; 4-5 meals/day evenly spaced, ~ 30% protein/day) significantly enhances weight loss, body composition, and cardiometabolic health in obese men and women. Whether an IF1-P or IF2-P, matched for weekly energy intake (EI) and expenditure (EE), is superior for weight loss, body composition, and cardiometabolic health is unknown. METHODS: This randomized control study directly compared an IF1-P (n = 10) versus an IF2-P (n = 10) diet on weight loss and body composition, cardiovascular (blood pressure and lipids), hormone, and hunger responses in 20 overweight men and women during a 4-week weight loss period. Participants received weekly dietary counseling and monitoring of compliance from a registered dietitian. All outcome variables were assessed pre (week 0) and post (week 5). RESULTS: Both groups significantly reduced body weight, waist circumference, percent body fat, fat mass, hunger, blood pressure, lipids, glucose, and increased percent fat-free mass (p < 0.05). However, IF2-P resulted in significantly greater reductions in body weight (-29%) and waist circumference (-38%) compared to IF1-P (p < 0.05), and showed a strong tendency for greater reductions in fat mass, glucose, and hunger levels (p < 0.10) despite similar weekly total EI (IF1-P, 9058 ± 692 vs. IF2-P, 8389 ± 438 kcals/week; p = 0.90), EE (~ 300 kcals/day; p = 0.79), and hormone responses (p > 0.10). CONCLUSIONS: These findings support short-term IF1-P and IF2-P to optimize weight loss and improve body composition, cardiometabolic health, and hunger management, with IF2-P providing enhanced benefits in overweight women and men. TRIAL REGISTRATION: This trial was registered March 03, 2020 at www. CLINICALTRIALS: gov as NCT04327141 .

Morning Exercise Reduces Abdominal Fat and Blood Pressure in Women; Evening Exercise Increases Muscular Performance in Women and Lowers Blood Pressure in Men.

The ideal exercise time of day (ETOD) remains elusive regarding simultaneous effects on health and performance outcomes, especially in women. Purpose: Given known sex differences in response to exercise training, this study quantified health and performance outcomes in separate cohorts of women and men adhering to different ETOD. Methods: Thirty exercise-trained women (BMI = 24 ± 3 kg/m2; 42 ± 8 years) and twenty-six men (BMI = 25.5 ± 3 kg/m2; 45 ± 8 years) were randomized to multimodal ETOD in the morning (0600-0800 h, AM) or evening (1830-2030 h, PM) for 12 weeks and analyzed as separate cohorts. Baseline (week 0) and post (week 12) muscular strength (1-RM bench/leg press), endurance (sit-ups/push-ups) and power (squat jumps, SJ; bench throws, BT), body composition (iDXA; fat mass, FM; abdominal fat, Abfat), systolic/diastolic blood pressure (BP), respiratory exchange ratio (RER), profile of mood states (POMS), and dietary intake were assessed. Results: Twenty-seven women and twenty men completed the 12-week intervention. No differences at baseline existed between groups (AM vs PM) for both women and men cohorts. In women, significant interactions (p < 0.05) existed for 1RM bench (8 ± 2 vs 12 ± 2, ∆kg), pushups (9 ± 1 vs 13 ± 2, ∆reps), BT (10 ± 6 vs 45 ± 28, ∆watts), SJ (135 ± 6 vs 39 ± 8, ∆watts), fat mass (-1.0 ± 0.2 vs -0.3 ± 0.2, ∆kg), Abfat (-2.6 ± 0.3 vs -0.9 ± 0.5, ∆kg), diastolic (-10 ± 1 vs-5 ± 5, ∆mmHg) and systolic (-12.5 ± 2.7 vs 2.3 ± 3, mmHg) BP, AM vs PM, respectively. In men, significant interactions (p < 0.05) existed for systolic BP (-3.5 ± 2.6 vs -14.9 ± 5.1, ∆mmHg), RER (-0.01 ± 0.01 vs -0.06 ± 0.01, ∆VCO2/VO2), and fatigue (-0.8 ± 2 vs -5.9 ± 2, ∆mm), AM vs PM, respectively. Macronutrient intake was similar among AM and PM groups. Conclusion: Morning exercise (AM) reduced abdominal fat and blood pressure and evening exercise (PM) enhanced muscular performance in the women cohort. In the men cohort, PM increased fat oxidation and reduced systolic BP and fatigue. Thus, ETOD may be important to optimize individual exercise-induced health and performance outcomes in physically active individuals and may be independent of macronutrient intake.