Cardiocirculatory and Metabolic Responses to Low- and High-Load Squat Exercise in Young and Middle-Aged Individuals.

: The aim of this study was to assess the safety and feasibility of resistance training (RT) in middle-aged and young individuals by examining cardiocirculatory and metabolic responses to squat performed under low and high external loads as per current exercise prescription guidelines. : Eighteen RT-trained individuals (nine middle-aged individuals, including eight women who were equally distributed) performed a cycling incremental test for the determination of their maximal aerobic capacity and three sessions of RT, respectively, to determine their one repetition maximum (1RM) of squat and their physiological responses during different training protocols of squat with equal training loads (3 × 12 at 55% 1RM vs. 5 × 5 at 80% 1RM).

Evaluating the maximal rate of lactate accumulation and estimated maximal lactate steady state in cycling.

This study examined the reliability of the maximal rate of blood lactate (BLa) accumulation (VLa) and the, thereof, derived calculated power output at maximal La steady state (cP-MLSS). Additionally, cP-MLSS was compared with the second La thresholds determined by experts (LT), being an accurate and often used threshold concept. 13 physically active male participants (length: 182 ± 4 cm; body mass: 76.

Predicting Heart Rate Slow Component Dynamics: A Model Across Exercise Intensities, Age, and Sex.

Unlabelled: The heart rate slow component (HR) is an intensity-dependent HR increment that emerges during constant exercises, partially dissociated from metabolism (V˙O). The HR has been observed during constant-workload exercise in young and older adults. Unless this HR is accounted for, exercise prescription using HR targets lead to an undesired reduction in metabolic intensity over time.

Linear Modeling of the V̇O 2 /PO Relationship during Constant Work Rate Exercise.

Introduction: The linear and continuous increase in power output (PO) during ramp incremental (RI) exercise causes a distinct V̇O 2 /PO relationship compared with constant work rate (CWR) exercise. Current methods enabling a translation of ramp-derived PO to CWR PO assume a linear development of the CWR V̇O 2 /PO relationship in the heavy-intensity domain. This study aimed to model the RI versus CWR V̇O 2 /PO relationship to investigate whether the loss of mechanical efficiency above GET develops linearly.

The impact of skinfold thickness and exercise intensity on the reliability of NIRS in the vastus lateralis.

Purpose: The aims of this study were (1) to assess the test-retest reliability of the primary near infrared spectroscopy (NIRS) variables (i.e., StO, T[Hb], [HbO] and [HHb]) during cycling and (2) to investigate potential influences of exercise intensity and adipose tissue thickness (ATT) on this reliability.

The Utility of High-Intensity, Intermittent Exercise Protocols to Induce Fatigue for Screening Purposes in Jump-Landing Sports.

Short-term fatigue protocols simulating sports participation are scarce and not well-documented in jump-landing sports. Therefore, this study investigated physiological and physical responses following high-intensity, intermittent exercise protocols (HIIPs) with a standardized level of subjective exhaustion (Borg ≥18/20) and a modified fixed version of five circuits (HIIP-5) for future inclusion in biomechanical screening protocols. Twenty male volleyball and basketball players participated in this study to complete the HIIP and the HIIP-5.

A dive into the physiological responses to maximal apneas, O and CO tables in apnea novices.

Purpose: Apnea duration is dependent on three factors: oxygen storage, oxygen consumption, hypoxia and hypercapnia tolerance. While current literature focuses on maximal apneas to improve apnea duration, apnea trained individuals use timed-repeated submaximal apneas, called "O and CO tables". These tables claim to accommodate the body to cope with hypoxia and hypercapnia, respectively.

Apnoea as a novel method to improve exercise performance: A current state of the literature.

Acute breath-holding (apnoea) induces a spleen contraction leading to a transient increase in haemoglobin concentration. Additionally, the apnoea-induced hypoxia has been shown to lead to an increase in erythropoietin concentration up to 5 h after acute breath-holding, suggesting long-term haemoglobin enhancement. Given its potential to improve haemoglobin content, an important determinant for oxygen transport, apnoea has been suggested as a novel training method to improve aerobic performance.

Relationship of peak capillary blood lactate accumulation and body composition in determining the mechanical energy equivalent of lactate during sprint cycling.

Aim: A 15-s all-out sprint cycle test (i.e., νLa-test) and the post-exercise change in capillary blood lactate concentration is an emerging diagnostic tool that is used to quantify the maximal glycolytic rate.

A structural microsimulation model for demand-side cost-sharing in healthcare.

Demand-side cost-sharing reduces moral hazard in healthcare but increases exposure to out-of-pocket expenditure. We introduce a structural microsimulation model to evaluate both total and out-of-pocket expenditure for different cost-sharing schemes. We use a Bayesian mixture model to capture the healthcare expenditure distributions across different age-gender categories.

Reliability of power output, maximal rate of capillary blood lactate accumulation, and phosphagen contribution time following 15-s sprint cycling in amateur cyclists.

Based on Mader's mathematical model, the rate of capillary blood lactate concentration (νLa) following intense exercise is thought to reflect the maximal glycolytic rate. We aimed to investigate the reliability of important variables of Mader's model (i.e.

Characterizing the Exponential Profile of W' Recovery Following Partial Depletion.

Purpose: The aim of this study was to characterize W' recovery kinetics in response to a partial W' depletion. We hypothesized that W' recovery following a partial depletion would be better described by a biexponential than by a monoexponential model.

Methods: Nine healthy men performed a ramp incremental exercise test, three to five constant load trials to determine critical power and W', and 10 experimental trials to quantify W' depletion.

Pricing above value: Selling to a market with selection problems.

This paper shows that selection incentives in downstream markets distort upstream prices. It is possible for inputs to be priced above the value that the good has for final consumers. We apply this idea to pharmaceutical companies selling drugs to a health insurance market with selection problems.

Application and performance of heart-rate-based methods to estimate oxygen consumption at different exercise intensities in postmenopausal women.

Purpose: Heart rate (HR) is a widespread method to estimate oxygen consumption ( O), exercise intensity, volume, and energy expenditure. Still, accuracy depends on lab tests or using indexes like HR and HR. This study addresses HR indexes' applicability in postmenopausal women (PMW), who constitute over 50% of the aging population and may have unique characteristics (e.

Effect of acute heat exposure on the determination of critical power and W' in women and men.

The goal of this study was to investigate to what extent acute heat exposure would affect the parameters of the power-duration relationship, i.e. CP and W', using multiple constant workload tests to task failure, in women and men.

Minimum generosity levels in a competitive health insurance market.

An important condition for optimal health insurance is that the level of health care coverage is inversely related to the elasticity of demand. We show that this condition is not satisfied for voluntary deductibles in the Netherlands, which are optional deductibles on top of the mandatory deductible introduced by the Dutch government. We find that low-risk types, that mainly choose voluntary deductibles, have a lower elasticity of demand than high-risk types.

Critical power, W' and W' reconstitution in women and men.

Purpose: The aim of this study was to compare critical power (CP) and work capacity W', and W' reconstitution (W') following repeated maximal exercise between women and men.

Methods: Twelve women ([Formula: see text]O: 2.53 ± 0.

Muscle typology influences the number of repetitions to failure during resistance training.

This study examined whether muscle typology (muscle fibre type composition) is related to maximal strength and whether it can explain the high inter-individual variability in number of repetitions to failure during resistance training. Ninety-five resistance training novices (57 males) were assessed for their maximal isometric knee extension strength and muscle typology. Muscle typology was estimated by measuring carnosine in the soleus, gastrocnemius and/or vastus lateralis using proton magnetic resonance spectroscopy.

Can muscle typology explain the inter-individual variability in resistance training adaptations?

Considerable inter-individual heterogeneity exists in the muscular adaptations to resistance training. It has been proposed that fast-twitch fibres are more sensitive to hypertrophic stimuli and thus that variation in muscle fibre type composition is a contributing factor to the magnitude of training response. This study investigated if the inter-individual variability in resistance training adaptations is determined by muscle typology and if the most appropriate weekly training frequency depends on muscle typology.

Can We Accurately Predict Critical Power and W' from a Single Ramp Incremental Exercise Test?

Purpose: The purpose of this study was to examine the suitability of a single ramp incremental test to predict critical power (CP) and W' . We hypothesized that CP would correspond to the corrected power output (PO) at the respiratory compensation point (RCP) and W' would be calculable from the work done above RCP.

Methods: One hundred fifty-three healthy young people (26 ± 4 yr, 51.

Easy Prediction of the Maximal Lactate Steady-State in Young and Older Men and Women.

Maximal Lactate steady-state (MLSS) demarcates sustainable from unsustainable exercise and is used for evaluation/monitoring of exercise capacity. Still, its determination is physically challenging and time-consuming. This investigation aimed at validating a simple, submaximal approach based on blood lactate accumulation ([Δlactate]) at the third minute of cycling in a large cohort of men and women of different ages.

The magnitude and time-course of physiological responses to 9 weeks of incremental ramp testing.

Purpose: The aims of this study were to assess (1) the day-to-day variability in, and (2) the magnitude and time-course of adaptation of physiological parameters (i.e., maximal oxygen uptake [VO max], heart rate [HR], blood lactate concentration, respiratory exchange ratio [RER], ratings of perceived exertion [RPE], and time-to-exhaustion [TTE]) in response to an intervention involving three incremental ramp tests per week for 9 weeks.