Capsaicin (CAP) activates the transient receptor potential vanilloid 1 (TRPV1) channel on sensory neurons, improving ATP production, vascular function, fatigue resistance, and thus exercise performance. However, underlying mechanisms of CAP-induced ergogenic effects fatigue-resistance, remain elusive. To evaluate anti-fatigue CAP, 10 young healthy males performed constant-load cycling time to exhaustion (TTE) trials (85% maximal work rate) after ingestion placebo (PL; fiber) or CAP capsules...

Abstract 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 NIRS‐VOT exhibits sex‐ limb‐specificity may be acutely altered remains to elucidated. Thus, we investigated if there limb‐ sex specificity in tissue desaturation rates (DeO 2 ) NIRS‐VOT, and acute dietary capsaicin alter this muscle Young healthy men ( n = 25, 21 ± 4 years) women 20, 20 1 ingested either placebo...

Short, disturbed, and irregular sleep may contribute to blunted nocturnal blood pressure (BP) dipping, a predictor of cardiovascular disease. Black women (BLW) demonstrate less BP dipping poorer health than White (WHW). However, it remains unclear whether device-estimated metrics mediate the relation between race in young women. We hypothesized that would be partly mediated by duration, efficiency, regularity. Participants (20 BLW, 17 WHW) were 18-29 years old, normotensive, nonobese,...

Abstract Mitochondrial efficiency is a critical metabolic parameter with far‐reaching implications for tissue homeostasis. However, the direct measurement of oxygen consumption (VO 2 ) and ATP production from large sample in vivo remains challenging. Using phosphorus ( 31 P) proton 1 H) magnetic resonance spectroscopy (MRS), this study aimed to non‐invasively quantify skeletal muscle synthesis rate VO determine mitochondrial at rest during contraction humans. We assessed plantar flexor...

Background An acute bout of eccentric contractions (ECC) cause muscle fiber damage, inflammation, impaired function (MF) and soreness (MS). Individually, protein (PRO) antioxidant (AO) supplementation may improve some aspects recovery from ECC, though have yet to be combined. We sought determine if combined PRO AO (PRO + AO) improves MS MF following damaging ECC over alone.Methods Sixty sedentary college-aged males participated in a randomized, single–blind, parallel design study peak...

Abstract 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 paucity of information on the additive effects high-intensity interval (HIIE) acute heat stress. We aimed determine HIIE combination with performance. Methods Twelve active (peak O 2 consumption [VO 2peak ]: 47 ± 8 ml·O /min/kg) young adults were counterbalanced six sessions hot (HIIE-H, 30 1...

To determine the effects of wrist cooling on recovery from exercise-induced heat stress (EIHS) wearing firefighting personal protective equipment (PPE) and self-contained breathing apparatus.Using a single-blind, counterbalanced, crossover-design, in 11 healthy men, we measured heart rate (HR), HR variability (HRV), core temperature (TCore), thermal strain (TS), fatigue at rest, during 30-minute exercise PPE+SCBA, while band (control[off] vs cool[on]).No differences were observed between...

Dehydration impairs physiological function and physical performance, thus understanding effective rehydration strategies is paramount. Despite growing interest in natural rehydrating beverages, no study has examined maple water (MW).Purpose To investigate the efficacy of MW after exercise-induced dehydration.Methods Using a single-blind, counterbalanced, crossover design, we compared vs. maple-flavored bottled (control) 26 young healthy (22 ± 4 yrs., 24 kg/m2) males (n = 13) females...

Firefighting is a dangerous occupation and even training carries substantial risks. Self-contained breathing apparatus confidence courses (SCBACC) are common type of training.Compare the physiological strain SCBACC to live-fire (LFT) circuit (CT) among academy cadets.Cadets wore physiologic status monitors assess heart rate (HR) estimated core temperature (ECT) during CT, LFT, similar duration (33-38 min).Data from 52 cadet firefighters (28 ± 4 yrs old) were analyzed. ECT (38.6 0.4 vs 39.3...

With the emergence of severe acute respiratory syndrome 2 (SARS-CoV-2), leading to coronavirus disease 19 (COVID-19), a new class messenger RNA (mRNA) vaccines have been broadly used. These associated with inflammatory sides effects such as myo- and peri-carditis. Despite well-known link between inflammation endothelial dysfunction, it is unknown whether these may transiently impair function, therefore increase cardiovascular risk.To evaluate influence COVID-19-based mRNA on macro-...

Cigarette smoke exposure is a well-known risk factor for developing numerous chronic health conditions, including pulmonary disease and cardiometabolic disorders. However, the cellular mechanisms mediating toxicity of cigarette in extrapulmonary tissues are still poorly understood. Therefore, purpose this study was to characterize acute dose-dependent on mitochondrial metabolism by determining susceptibility sensitivity respiration from murine skeletal (gastrocnemius soleus) cardiac muscles,...

Blunted nocturnal blood pressure (BP) dipping, defined as less than 10% reduction in BP during sleep compared to wake, independently predicts cardiovascular disease. Short and disturbed associate with dipping young adults, Black women (BLW) demonstrate poorer health White (WHW) early adulthood. However, not known is if habitual, objectively estimated metrics mediate the relationship between race women. Thus, this study sought evaluate mediating effect of habitual duration effciency on...

Abstract The detection of a secondary inorganic phosphate (Pi) resonance, possible marker mitochondrial content in vivo, using phosphorus magnetic resonance spectroscopy ( 31 P‐MRS), poses technical challenges at 3 Tesla (T). Overcoming these is imperative for the integration this biomarker into clinical research. To evaluate repeatability and reliability measuring resting skeletal muscle alkaline Pi (Pi alk ) with P‐MRS T. After an initial set experiments on five subjects to optimize...

Low endogenous testosterone has been associated with increased cardiovascular risk in men.To determine the prevalence of low serum level (TT) a cohort male US career firefighters and to examine its relation left ventricular wall thickness (LVWT).We conducted cross-sectional study among 341 firefighters, (age: 37.5 ± 10.3 years; BMI: 28.9 4.5 kg/m2 ), who underwent an occupational medical screening examination. TT quartiles were determined, LVWT distribution them was plotted. Then, values...

The passive leg movement (PLM) technique is a non-invasive assessment of lower-limb vascular function. PLM methodologically simple to perform and utilizes Doppler ultrasound determine blood flow (LBF) through the common femoral artery at rest in response lower leg. LBF responses have been reported be mostly nitric oxide (NO)-mediated when performed young adults. Moreover, PLM-induced responses, as well NO contribution are reduced with age various diseased populations, demonstrating clinical...

Introduction: Mitochondrial effciency provides an additional mechanism to fine-tune oxidative phosphorylation rate match ATP demand in skeletal muscle with far-reaching consequences on exercise tolerance. However, the direct measurement of both oxygen consumption (VO 2 ) and production from same region contracting vivo remains a technical challenge. Purpose: Using innovative approach combining noninvasive phosphorus proton magnetic resonance spectroscopy ( 31 P/ 1 H-MRS), present study aimed...

Alkaline inorganic phosphate (Pi alk ) is a promising biomarker of mitochondrial content in vivo that technically challenging to assess at 3T. The absolute and relative reproducibility Pi the quadriceps muscle across two visits were assessed healthy sedentary-to-moderately active young adults using 31 P-MRS results this study demonstrate an excellent quantification Pialk 3T provided coil positioned mid-thigh.

Obtaining sufficient sleep duration in youth may prevent childhood obesity and other poor cardiometabolic outcomes. Sleep irregularity, i.e. variability nightly duration, is a metric of health that has also been associated with increased risk youth. The transition from to adolescence characterized by marked delays wake timing, which directly conflicts societal influences (e.g., early school start times). Thus, adolescents are less likely meet recommendations than children. However, the...

Duchenne (DMD) and Becker (BMD) muscular dystrophinopathies are rare muscle wasting disorders with a high mortality rate, predominately of cardiac origin. Heart rate variability (HRV) is robust measure autonomic balance known to be impaired in boys dystrophinopathies. HRV DMD/BMD typically reported time frequency domains (i.e. linear scales) but nonlinear associated the structure heart dynamics may provide complementary diagnostic information on pathological HRV. However, there limited data...

Eccentric contractions (ECC) result in muscle fiber damage from mechanical stress and a pro-inflammatory, pro-oxidant response, leading to decline function rise soreness. Individually, protein (PRO) antioxidant (AO) supplements have been shown improve recovery after eccentric exercise-induced damage, though yet be combined. PURPOSE: Determine if combined supplement (PRO+AO) improves soreness (MS) (MF) following fatiguing over PRO alone or control. METHODS: 60 sedentary college-aged males...