No effect of aerobic fitness on exercise-induced diaphragm fatigue in females.

We tested the hypothesis that the incidence and magnitude of diaphragm fatigue following high-intensity exercise would be lower in females with a high aerobic capacity (Hi-Fit) compared with healthy females with an average aerobic fitness (Avg-Fit). Participants were assigned to groups based on their peak O uptake (V̇o) obtained during cycle exercise: Hi-Fit = 9, V̇o ≥ 56.1 ± 3.

Acute partial sleep deprivation attenuates blood pressure responses to cycling exercise.

Exaggerated blood pressure (BP) responses during exercise are independently associated with future development of hypertension. Partial sleep deprivation (PSD) can increase 24-h ambulatory BP, but the effects on exercise BP are unclear. We hypothesized that acute PSD would augment the BP response to constant load cycling exercise and a 20-min time trial.

Effects of intensified training with insufficient recovery on joint level and single muscle fibre mechanical function: the role of myofibrillar Ca sensitivity.

Intense exercise training with insufficient recovery time is associated with reductions in neuromuscular performance. However, it is unclear how single muscle fibre mechanical function and myofibrillar Ca sensitivity contribute to these impairments. We investigated the effects of overload training on joint-level neuromuscular performance and cellular-level mechanical function.

A Characterization of the Cardiac Physiology and Aortic Pulse Wave Properties of Artistic Swimmers Across Competitive Levels.

Purpose: The distinct physical and environmental stressors of artistic swimming (previously termed synchronized swimming) result in unique hemodynamic stimuli. Given that the hemodynamic stress associated with participation in an exercise modality drives adaptation of the heart and central vasculature, artistic swimming may produce a distinct cardiovascular phenotype. Presumably, athletes competing at the highest levels also have greater training exposure and thus exhibit more adaptation.

Assessing Leg Blood Flow and Cardiac Output During Running Using Thermodilution.

Cardiac output (Q̇) and leg blood flow (Q̇) can be measured simultaneously with high accuracy using transpulmonary and femoral vein thermodilution with a single-bolus injection. The invasive measure has offered important insight into leg hemodynamics and blood flow distribution during exercise. Despite being the natural modality of exercise in humans, there has been no direct measure of Q̇ while running in humans.

High-intensity interval versus moderate-intensity continuous cycling training in Parkinson's disease: a randomized trial.

Exercise training is recommended to improve the quality of life in those living with Parkinson's disease (PD); however, the optimal prescription to improve cardiorespiratory fitness and disease-related motor symptoms remains unknown. Twenty-nine participants with PD were randomly allocated to either 10 wk of high-intensity interval training (HIIT) ( = 15; 6 female) or moderate-intensity continuous training (MICT) ( = 14; 5 female). The primary outcome was the change in maximal oxygen consumption (V̇o).

Blood Flow-Restricted Training and Time Trial Performance: A Cohort Study of World-Class Rowers.

Introduction: This study aimed to explore the potential impact of incorporating blood flow restriction (BFR) training within a training block characterized by minimal high-intensity work on 2000-m rowing ergometer time trial (TT) performance in elite/world-class rowers. Physiological markers often associated with endurance performance (maximal aerobic capacity, V̇O 2max ; blood lactate thresholds and hemoglobin mass, Hb mass ) were measured to determine whether changes are related to an improvement in performance.

Methods: Using a quasi-experimental, observational study design (no control group), 2000-m TT performance, V̇O 2max , submaximal work rates eliciting blood lactate concentrations of ~2 and ~4 mmol·L -1 , and Hb mass were measured before and after 4 wk of noncompetitive season training, which included BFR rowing.

Carbohydrate Ingestion Increases Interstitial Glucose and Mitigates Neuromuscular Fatigue during Single-Leg Knee Extensions.

Introduction: We aimed to investigate the neuromuscular contributions to enhanced fatigue resistance with carbohydrate (CHO) ingestion and to identify whether fatigue is associated with changes in interstitial glucose levels assessed using a continuous glucose monitor (CGM).

Methods: Twelve healthy participants (six males, six females) performed isokinetic single-leg knee extensions (90°·s -1 ) at 20% of the maximal voluntary contraction (MVC) torque until MVC torque reached 60% of its initial value (i.e.

The addition of blood flow restriction during resistance exercise does not increase prolonged low-frequency force depression.

At a given exercise intensity, blood flow restriction (BFR) reduces the volume of exercise required to impair post-exercise neuromuscular function. Compared to traditional exercise, the time course of recovery is less clear. After strenuous exercise, force output assessed with electrical muscle stimulation is impaired to a greater extent at low versus high stimulation frequencies, a condition known as prolonged low-frequency force depression (PLFFD).

Investigating the Relevance of Maximal Speed and Acceleration in Varsity-Level Female Ice Hockey Players.

Purpose: To characterize and compare female ice hockey players' peak skating speed and acceleration ability during linear sprints and gameplay. We also sought to quantify the time spent at various speeds and the frequency of accelerations at different thresholds during games.

Methods: Seventeen varsity-level female ice hockey players (20 [1.

Effect of blood flow restriction and electrical muscle stimulation on human glycemic response to a glucose challenge.

Purpose: To determine whether reduced tissue oxygen availability through blood flow restriction (BFR) alone, or in combination with electrically induced muscle contractions, can improve glucose clearance after an acute glucose challenge.

Methods: In a randomized crossover design, 21 young participants (females: 12) were allocated to perform 1) electrical muscle stimulation (EMS), 2) BFR, 3) EMS + BFR or 4) no treatment (control). Participants completed each condition immediately preceding a 2 h oral glucose tolerance test (100 g).

Cannabis containing THC impairs 20-min cycling time trial performance irrespective of the method of inhalation.

Herein, we examine the human exercise response following cannabis inhalation, taking into consideration varied cannabinoid concentrations and different inhalation methods. A semirandomized crossover study design was used, with measures of perceived exertion and physiological responses to submaximal and maximal exercise. Participants ( = 14, 9 males 5 females) completed exercise after ) smoking Δ-9-tetrahydrocannabinol (THC)-predominant cannabis (S-THC), ) inhaling aerosol (vaporizing) from THC-predominant cannabis (V-THC), ) inhaling aerosol from cannabidiol (CBD)-predominant cannabis (V-CBD), or ) under control conditions.

Altered carbohydrate oxidation during exercise in overreached endurance athletes is applicable to training monitoring with continuous glucose monitors.

Purpose: The purpose of the study was to investigate whether carbohydrate utilization is altered during exercise in overreached endurance athletes and examine the utility of continuous glucose monitors (CGM) to detect overreaching status.

Methods: Eleven endurance athletes (M:8, F:3) completed a 5-week training block consisting of 1 week of reduced training (PRE), 3 weeks of high-intensity overload training (POST), and 1 week of recovery training (REC). Participants completed a Lamberts and Lambert Submaximal Cycling Test (LSCT) and 5 km time-trial at PRE, POST, and REC time points, 15 min following the ingestion of a 50 g glucose beverage with glucose recorded each minute via CGM.

Acute oral antioxidant consumption does not alter brachial artery flow mediated dilation in young adults independent of exercise training status.

Endothelium-dependent vasodilation can be tested using a variety of shear stress paradigms, some of which may involve the production of reactive oxygen species. The purpose of this study was to compare different methods for assessing endothelial function and their specific involvement of reactive oxygen species and influence of aerobic training status. Twenty-nine (10 F) young and healthy participants (VOmax: 34-74 mL·kg·min) consumed either an antioxidant cocktail (AOC; vitamin C, vitamin E, α-lipoic acid) or placebo (PLA) on each of two randomized visits.

Cardiovascular responses to combined mechanoreflex and metaboreflex activation in healthy adults: effects of sex and low- versus high-hormone phases in females.

Females generally have smaller blood pressure (BP) responses to isolated muscle mechanoreflex and metaboreflex activation compared with males, which may explain sex differences in BP responses to voluntary exercise. The mechanoreflex may be sensitized during exercise, but whether mechanoreflex-metaboreflex interactions differ by sex or variations in sex hormones remains unknown. Thirty-one young healthy subjects (females, = 16) performed unilateral passive cycling (mechanoreflex), active cycling (40% peak Watts), postexercise circulatory occlusion (PECO; metaboreflex), and passive cycling combined with PECO (combined mechanoreflex and metaboreflex activation).

Impact of Blood Flow Restriction Exercise on Central Hemodynamics and Fluid Regulating Hormones.

Purpose: The purpose of this study is to characterize both the efficacy of altered restriction pressures and consequences of optimized blood flow restriction (BFR) for altering the cardiovascular and fluid regulating response in humans.

Methods: This work comprised a series of related trials. Phase 1: during semi-recumbent cycling (5 min, 60 W) with BFR at 0%, 50%, 75%, 100%, and 125% of participants' lowest arterial occlusion pressure (LOP) echocardiographic images were collected alongside continuous heart rate (HR) and blood pressure (BP).

Physiological and clinical responses to cycling 7850 km over 85 days in a physically active middle-aged man with idiopathic Parkinson's disease.

This case characterizes the clinical motor, perceived fatigue, gait and balance, cardiovascular, neuromuscular, and cardiopulmonary responses after cycling 7850 km over 85 days in a physically active 57-year-old male with idiopathic Parkinson's disease (PD). The participant cycled 73/85 days (86%); averaging 107.5 ± 48.

Renal vascular conductance is unrelated to leg vascular conductance or muscle sympathetic nerve activity at rest and during stress in humans.

The sympathetic nervous system is important for cardiovascular regulation, particularly during acute stress. Efferent sympathetic outflow can be regulated in an organ-dependent manner, but whether renal and leg vasoconstriction are associated at rest or during sympathetic stressors is unknown. Therefore, we sought to determine the relationships between muscle sympathetic nerve activity (MSNA), leg vascular conductance (LVC), and renal vascular conductance (RVC) at rest and during common laboratory-based sympathoexcitatory stimuli in a cohort of young healthy adults.

Time Management Strategies of Rock Climbers in World Cup Bouldering Finals.

Competitive rock climbing recently made its Olympic debut, but minimal published research exists regarding training and competition strategies. Time management strategies define the structured approach climbers take in bouldering competitions to successfully obtain a "top" or a "zone" hold. During finals rounds of the International Federation of Sport Climbing bouldering competitions, climbers are allotted 240 s to complete a boulder.

Ergogenic effect of ischemic preconditioning is not directly conferred to isolated skeletal muscle via blood.

Purpose: Ischemic preconditioning (IPC) in humans has been demonstrated to confer ergogenic benefit to aerobic exercise performance, with an improvement in the response rate when the IPC stimulus is combined with concurrent exercise. Despite potential performance improvements, the nature of the neuronal and humoral mechanisms of conferral and their respective contributions to ergogenic benefit remain unclear. We sought to examine the effects of the humoral component of ischemic preconditioning on skeletal muscle tissue using preconditioned human serum and isolated mouse soleus.

Blood flow restriction does not alter the early hypertrophic signaling and short-term adaptive response to resistance exercise when performed to task failure.

Previous research supports that low-load resistance exercise with blood flow restriction (LL-BFR) acutely increases physiological responses and muscle mass accrual compared with low-load resistance exercise (LL-RE) alone. However, most studies have work-matched LL-BFR and LL-RE. Completing sets to similar perceived efforts, thereby allowing for a variable amount of work, may provide a more ecologically valid approach to compare LL-BFR and LL-RE.

Ischemic Preconditioning Acutely Improves Functional Sympatholysis during Handgrip Exercise in Healthy Males but not Females.

Purpose: Ischemic preconditioning (IPC), a procedure that involves the cyclic induction of limb ischemia and reperfusion via tourniquet inflation, has been reported to improve exercise capacity and performance, but the underlying mechanisms remain unclear. During exercise, sympathetically mediated vasoconstriction is dampened in active skeletal muscle. This phenomenon, termed functional sympatholysis, plays a critical role in maintaining oxygen delivery to working skeletal muscle and may contribute to determining exercise capacity.