Exercise training-induced speeding of kinetics is not intensity domain-specific or correlated with indices of exercise performance.

Purpose: This study examined the effect of 3 and 6 weeks of intensity domain-based exercise training on kinetics changes and their relationship with indices of performance.

Methods: Eighty-four young healthy participants (42 M, 42 F) were randomly assigned to six groups (14 participants each, age and sex-matched) consisting of: continuous cycling in the (1) moderate (MOD)-, (2) lower heavy (HVY1)-, and (3) upper heavy-intensity (HVY2)- domain; interval cycling in the (4) severe-intensity domain (i.e.

Methodological considerations on near-infrared spectroscopy derived muscle oxidative capacity.

Purpose: Different strategies for near-infrared spectroscopy (NIRS)-derived muscle oxidative capacity assessment have been reported. This study compared and evaluated (I) approaches for averaging trials; (II) NIRS signals and blood volume correction equations; (III) the assessment of vastus lateralis (VL) and tibialis anterior (TA) muscles in two fitness levels groups.

Methods: Thirty-six participants [18 chronically trained (CT: 14 males, 4 females) and 18 untrained (UT: 10 males, 8 females)] participated in this study.

Heart Rate Variability Thresholds: Agreement with Established Approaches and Reproducibility in Trained Females and Males.

Purpose: To determine in trained females and males i) the agreement between the gas exchange threshold (GET), lactate threshold 1 (LT1), and heart rate variability threshold 1 (HRVT1), as well as between the respiratory compensation point (RCP), lactate threshold 2 (LT2), and heart rate variability threshold 2 (HRVT2), and ii) the reproducibility of HRVT1 and HRVT2 during 2-min incremental step protocols.

Methods: Fifty-seven trained participants (24 females) completed a 2-min step incremental test to task failure. Nineteen participants (eight females) completed a second test to evaluate reproducibility.

Heavy-, Severe-, and Extreme-, but Not Moderate-Intensity Exercise Increase V̇o 2max and Thresholds after 6 wk of Training.

Introduction: This study assessed the effect of individualized, domain-based exercise intensity prescription on changes in maximal oxygen uptake (V̇O 2max ) and submaximal thresholds.

Methods: Eighty-four young healthy participants (42 females, 42 males) were randomly assigned to six age, sex, and V̇O 2max -matched groups (14 participants each). Groups performed continuous cycling in the 1) moderate (MOD), 2) lower heavy (HVY1), and 3) upper heavy-intensity (HVY2) domain; interval cycling in the form of 4) high-intensity interval training (HIIT) in the severe-intensity domain, or 5) sprint-interval training (SIT) in the extreme-intensity domain; or no exercise for 6) control (CON).

Recommendations for Women in Mountain Sports and Hypoxia Training/Conditioning.

The (patho-)physiological responses to hypoxia are highly heterogeneous between individuals. In this review, we focused on the roles of sex differences, which emerge as important factors in the regulation of the body's reaction to hypoxia. Several aspects should be considered for future research on hypoxia-related sex differences, particularly altitude training and clinical applications of hypoxia, as these will affect the selection of the optimal dose regarding safety and efficiency.

Sodium bicarbonate induces alkalosis, but improves high-intensity cycling performance only when participants expect a beneficial effect: a placebo and nocebo study.

The study aimed to investigate the effects of sodium bicarbonate (NaHCO) intake with divergent verbal and visual information on constant load cycling time-to-task failure, conducted within the severe intensity domain. Fifteen recreational cyclists participated in a randomized double-blind, crossover study, ingesting NaHCO or placebo (i.e.

Women at Altitude: Sex-Related Physiological Responses to Exercise in Hypoxia.

Sex differences in physiological responses to various stressors, including exercise, have been well documented. However, the specific impact of these differences on exposure to hypoxia, both at rest and during exercise, has remained underexplored. Many studies on the physiological responses to hypoxia have either excluded women or included only a limited number without analyzing sex-related differences.

Performance fatigability and recovery after dynamic multi-joint maximal exercise in elbow flexors versus knee extensors.

Elbow flexors (EFs) and knee extensors (KEs) have shown differences in performance fatigability and recovery of neuromuscular function after isometric and isotonic single-joint fatiguing contractions. However, dynamic multi-joint movements are more representative of real-world activities. The aim of the study was to assess central and peripheral mechanisms of fatigability after either arm-cranking or cycling.

Decrease in work rate in order to keep a constant heart rate: biomarker of exercise intolerance following a 10-day bed rest.

Aerobic exercise prescription is often set at specific heart rate (HR) values. Previous studies demonstrated that during exercise carried out at a HR slightly above that corresponding to the gas exchange threshold (GET), work rate (WR) has to decrease in order to maintain HR constant. We hypothesized a greater WR decrease at a fixed HR after simulated microgravity/inactivity (bed rest, BR).

Fitness Level- and Sex-Related Differences in Macrovascular and Microvascular Responses during Reactive Hyperemia.

Purpose: Reactive hyperemia (RH) is widely used for the investigation of macrovascular (flow-mediated dilation, or FMD) and microvascular (near-infrared spectroscopy-vascular occlusion test, or NIRS-VOT) function. Mixed results have been reported on fitness level- and sex-related differences in FMD outcomes, and little is known about microvascular differences in untrained and chronically trained males and females.

Methods: Fifteen chronically trained (CT: 8 males, 7 females) and 16 untrained (UT: 8 males, 8 females) individuals participated in this study.

Peripheral impairments of oxidative metabolism after a 10-day bed rest are upstream of mitochondrial respiration.

In order to identify peripheral biomarkers of impaired oxidative metabolism during exercise following a 10-day bed rest, 10 males performed an incremental exercise (to determine peak pulmonary V̇O (V̇O p)) and moderate-intensity exercises, before (PRE) and after (POST) bed rest. Blood flow response was evaluated in the common femoral artery by Eco-Doppler during 1 min of passive leg movements (PLM). The intramuscular matching between O delivery and O utilization was evaluated by near-infrared spectroscopy (NIRS).

Beet on Alps: Time-course changes of plasma nitrate and nitrite concentrations during acclimatization to high-altitude.

Nitric oxide seems to be involved in the altitude acclimatization process due to its ability to regulate pulmonary, cardiovascular and muscular responses to hypoxia. In this study, we investigated the plasma nitrate (NO) and nitrite (NO) response to hypobaric hypoxia in two groups of lowlanders exposed at different altitudes. For seven days, fourteen subjects were evaluated at Casati Hut (3269 m a.

Effect of acute nitrite infusion on contractile economy and metabolism in isolated skeletal muscle in situ during hypoxia.

Key Points: Increased plasma nitrite concentrations may have beneficial effects on skeletal muscle function. The physiological basis explaining these observations has not been clearly defined and it may involve positive effects on muscle contraction force, microvascular O delivery and skeletal muscle oxidative metabolism. In the isolated canine gastrocnemius model, we evaluated the effects of acute nitrite infusion on muscle force and skeletal muscle oxidative metabolism.

Effects of Different Training Interventions on the Recovery of Physical and Neuromuscular Performance After a Soccer Match.

Trecroci, A, Porcelli, S, Perri, E, Pedrali, M, Rasica, L, Alberti, G, Longo, S, and Iaia, FM. Effects of different training interventions on the recovery of physical and neuromuscular performance after a soccer match. J Strength Cond Res 34(8): 2189-2196, 2020-In competitive soccer, players are frequently required to play in periods with congested fixtures in which they have limited time to recover between matches (3-4 days).

New On-Water Test for the Assessment of Blood Lactate Response to Exercise in Elite Kayakers.

Purpose: Lactate thresholds are physiological parameters used to train athletes and monitor performance or training. Currently, the assessment of lactate thresholds in kayakers is performed in a laboratory setting utilizing specific ergometers; however, laboratory tests differ from on-water evaluation for several reasons. The aim of this study was to assess reliability and validity of a new on-water incremental test for the assessment of blood lactate response to exercise in flat-water kayakers.

Ergogenic effects of beetroot juice supplementation during severe-intensity exercise in obese adolescents.

Previous studies showed a higher O cost of exercise, and therefore, a reduced exercise tolerance in patients with obesity during constant work rate (CWR) exercise compared with healthy subjects. Among the ergogenic effects of dietary nitrate ([Formula: see text]) supplementation in sedentary healthy subjects, a reduced O cost and enhanced exercise tolerance have often been demonstrated. The aim of this study was to evaluate the effects of beetroot juice (BR) supplementation, rich in [Formula: see text], on physiological variables associated with exercise tolerance in adolescents with obesity.

Triggered intravoxel incoherent motion MRI for the assessment of calf muscle perfusion during isometric intermittent exercise.

The main aim of this paper was to propose triggered intravoxel incoherent motion (IVIM) imaging sequences for the evaluation of perfusion changes in calf muscles before, during and after isometric intermittent exercise. Twelve healthy volunteers were involved in the study. The subjects were asked to perform intermittent isometric plantar flexions inside the MRI bore.

Comparison between Slow Components of HR and V˙O2 Kinetics: Functional Significance.

Purpose: Aerobic exercise prescription is often based on a linear relationship between pulmonary oxygen consumption (V˙O2) and heart rate (HR). The aim of the present study was to test the hypothesis that during constant work rate (CWR) exercises at different intensities, the slow component of HR kinetics occurs at lower work rate and is more pronounced that the slow component of V˙O2 kinetics.

Methods: Seventeen male (age, 27 ± 4 yr) subjects performed on a cycle ergometer an incremental exercise to voluntary exhaustion and several CWR exercises: 1) moderate CWR exercises, below gas exchange threshold (GET); 2) heavy CWR exercise, at 45% of the difference between GET and V˙O2 peak (Δ); 3) severe CWR exercise, at 95% of Δ; 4) "HRCLAMPED" exercise in which work rate was continuously adjusted to maintain a constant HR, slightly higher than that determined at GET.

Effects of a Short-Term High-Nitrate Diet on Exercise Performance.

It has been reported that nitrate supplementation can improve exercise performance. Most of the studies have used either beetroot juice or sodium nitrate as a supplement; there is lack of data on the potential ergogenic benefits of an increased dietary nitrate intake from a diet based on fruits and vegetables. Our aim was to assess whether a high-nitrate diet increases nitric oxide bioavailability and to evaluate the effects of this nutritional intervention on exercise performance.

Aerobic Fitness Affects the Exercise Performance Responses to Nitrate Supplementation.

Purpose: Dietary nitrate supplementation has been shown to reduce O2 cost of submaximal exercise, improve exercise tolerance, and enhance performance in moderately trained individuals. In contrast, data have been provided that elite athletes do not benefit from nitrate supplementation. The aim of this study was to evaluate the effects of short-term nitrate supplementation on endurance performance in subjects with different levels of aerobic fitness.