Differentiating acute fatigue and overreaching during intensified training using a recursive least squares algorithm combined with the variable dose-response model.

Purpose: This study aimed to investigate whether the variable dose-response model, with estimates free to vary over time, can account for overreaching during intensified training in swimmers.

Methods: A time-varying model using a recursive least squares algorithm was applied to data from eight swimmers collected over 61 weeks, comprising five training cycles. Each data set included daily training load calculated from pool kilometers and dry land training equivalents, and performance measured twice weekly from 50 m trials.

Reliability and Validity of Predicted Performance in the Severe-Intensity Domain From the 3-Minute All-Out Running Test.

Purpose: The aim of this study was to analyze the reliability and validity of the predicted distance-time relationship in the severe-intensity domain from a 3-minute all-out running test (3MT).

Methods: Twelve runners performed two 3MTs (test #1 and test #2) on an outdoor 400-m track after familiarization. Eighteen-hertz Global Positioning System data were used to estimate critical speed (CS) and distance covered above CS (D').

Neuromuscular and autonomic function is fully recovered within 24 h following a sprint interval training session.

Background: Recovery is a key factor to promote adaptations and enhance performance. Sprint Interval Training (SIT) is known to be an effective approach to improve overall physical function and health. Although a 2-day rest period is given between SIT sessions, the time-course of recovery after SIT is unknown.

Changes in power-force-velocity profile induced by 2 weeks of sprint interval training.

Background: This study aimed to determine the effects of a running sprint interval training protocol (R-SIT) on the sprint acceleration mechanical properties and jump performance. Eleven young male basketball players performed 6 R-SIT sessions for 2 weeks.

Methods: Each session consisted of 30-second running bouts repeated 4 to 7 times interspersed by 4 minutes of recovery.

Validity and Accuracy of Impulse-Response Models for Modeling and Predicting Training Effects on Performance of Swimmers.

Purpose: The aim of this study was to compare the suitability of models for practical applications in training planning.

Methods: We tested six impulse-response models, including Banister's model (Model Ba), a variable dose-response model (Model Bu), and indirect-response models differing in the way they account or not for the effect of previous training on the ability to respond effectively to a given session. Data from 11 swimmers were collected during 61 wk across two competitive seasons.

Dynamic Force Production Capacities Between Coronary Artery Disease Patients vs. Healthy Participants on a Cycle Ergometer.

Background: The force-velocity-power (FVP) profile is used to describe dynamic force production capacities, which is of great interest in training high performance athletes. However, FVP may serve a new additional tool for cardiac rehabilitation (CR) of coronary artery disease (CAD) patients. The aim of this study was to compare the FVP profile between two populations: CAD patients vs.

Exercise Frequency Determines Heart Rate Variability Gains in Older People: A Meta-Analysis and Meta-Regression.

Background: Previous studies have suggested that exercise training improves cardiac autonomic drive in young and middle-aged adults. In this study, we discuss the benefits for the elderly.

Objectives: We aimed to establish whether exercise still increases heart rate variability (HRV) beyond the age of 60 years, and to identify which training factors influence HRV gains in this population.

Regulation of Akt-mTOR, ubiquitin-proteasome and autophagy-lysosome pathways in locomotor and respiratory muscles during experimental sepsis in mice.

Sepsis induced loss of muscle mass and function contributes to promote physical inactivity and disability in patients. In this experimental study, mice were sacrificed 1, 4, or 7 days after cecal ligation and puncture (CLP) or sham surgery. When compared with diaphragm, locomotor muscles were more prone to sepsis-induced muscle mass loss.

From an indirect response pharmacodynamic model towards a secondary signal model of dose-response relationship between exercise training and physical performance.

The aim of this study was to test the suitability of using indirect responses for modeling the effects of physical training on performance. We formulated four different models assuming that increase in performance results of the transformation of a signal secondary to the primary stimulus which is the training dose. The models were designed to be used with experimental data with daily training amounts ascribed to input and performance measured at several dates ascribed to output.

Modeling the responses to resistance training in an animal experiment study.

The aim of the present study was to test whether systems models of training effects on performance in athletes can be used to explore the responses to resistance training in rats. 11 Wistar Han rats (277 ± 15 g) underwent 4 weeks of resistance training consisting in climbing a ladder with progressive loads. Training amount and performance were computed from total work and mean power during each training session.

Perceived training intensity and performance changes quantification in judo.

The objective of this study was to determine the methods of quantification for training and performance, which would be the most appropriate for modeling the responses to long-term training in cadet and junior judo athletes. For this, 10 young male judo athletes (15.9 ± 1.

Modeling of performance and ANS activity for predicting future responses to training.

Purpose: Our aim was to assess whether we can predict satisfactorily performance in swimming and high frequency power (HF power) of heart rate variability from the responses to previous training. We have tested predictions using the model of Banister and the variable dose-response model.

Methods: Data came from ten swimmers followed during 30 weeks of training with performance and HF power measured each week.

Modelling training response in elite female gymnasts and optimal strategies of overload training and taper.

The aim of the study is the modelling of training responses with a variable dose-response model in a sport discipline that requires highly complex coordination. We propose a method to optimise the training programme plan using the potential maximal performance gain associated with overload and tapering periods. Data from five female elite gymnasts were collected over a 3-month training period.

A model for the training effects in swimming demonstrates a strong relationship between parasympathetic activity, performance and index of fatigue.

Competitive swimming as a physical activity results in changes to the activity level of the autonomic nervous system (ANS). However, the precise relationship between ANS activity, fatigue and sports performance remains contentious. To address this problem and build a model to support a consistent relationship, data were gathered from national and regional swimmers during two 30 consecutive-week training periods.

A mixed-effects model of the dynamic response of muscle gene transcript expression to endurance exercise.

Altered expression of a broad range of gene transcripts after exercise reflects the specific adjustment of skeletal muscle makeup to endurance training. Towards a quantitative understanding of this molecular regulation, we aimed to build a mixed-effects model of the dynamics of co-related transcript responses to exercise. It was built on the assumption that transcript levels after exercise varied because of changes in the balance between transcript synthesis and degradation.

A comparison of modelling procedures used to estimate the power-exhaustion time relationship.

This study aimed to test the consistency of using the power required to elicit maximal oxygen uptake during incremental test (P (t)) to demarcate the range of power intensity in the modelling of the power-exhaustion time relationship. Different mathematical procedures were tested using data from ten subjects exercising on a cycle ergometer. After the determination of P (t) and the power at the ventilatory threshold, the subjects did six tests at constant power to exhaustion within 2-15 min.

Computer simulations assessing the potential performance benefit of a final increase in training during pre-event taper.

A nonlinear model of training responses was utilized to test whether a 2-phase taper could be more effective than a traditional linear taper. Simulations were conducted using model parameters previously determined in 6 nonathletes trained on a cycle ergometer (non-ATH) and 7 elite swimmers trained in sport-specific conditions (ATH). Linear and 2-phase tapers were compared after a 28-day overload period at 120% of normal training.

A comparison of lactate indices during ramp exercise using modelling techniques and conventional methods.

The aim of this study was to compare the lactate indices provided by single- and double-breakpoint models with lactate thresholds obtained with conventional methods. Arterial samples for the determination of lactate concentrations were drawn from eight participants at rest and every minute during a ramp test (15 W x min(-1)) on a cycle ergometer. Lactate thresholds were determined from a blood lactate concentration equal to 4 mM (LT(4)), from an increase of 1 mM above the resting level (Delta1 mM), and from indirect methods using ventilatory parameters.

Implications of breath-by-breath oxygen uptake determination on kinetics assessment during exercise.

We tested that the breath-by-breath V(O2) determination by an algorithm termed BR did not bias the kinetics parameters. It was compared to two other algorithms using a correction for changes in lung gas stores between two successive breaths (AU, W) and one without correction (NC). Ten healthy male subjects cycled 10 min at 15 and 30 W below and above ventilatory threshold (VT) after 3 min at 0 W.

Effect of acute hypoxia on central fatigue during repeated isometric leg contractions.

To determine whether hypoxia has a direct influence on the central command independently of the working muscles, 16 subjects performed intermittent isometric unilateral knee extensions until exhaustion either in normobaric hypoxia (inspired O(2) fraction=0.11, arterial oxygen saturation approximately 84%) or in normoxia while the knee extensor muscles were exposed to circulatory occlusion with a 250 mmHg cuff. Among the subjects, 11 also performed the tests in hypoxia and normoxia without occlusion.

A model study of optimal training reduction during pre-event taper in elite swimmers.

The aim of this study was to assess responses to taper in elite athletes using computer simulations. Parameters of a non-linear model were derived from training and performance data over two seasons for eight elite swimmers. The fit between modelled and actual performances was statistically significant for each swimmer (r(2) = 0.

Accumulated oxygen deficit during ramp exercise.

This study aimed to compare oxygen deficit during exhaustive ramp exercise (OD ramp and OD lag) with maximal oxygen deficit during a high-intensity constant-power test (MAOD). OD ramp was estimated from the difference between oxygen demand and actual oxygen uptake. OD lag was estimated using a simple equation assuming a linear increase in oxygen uptake lagging behind metabolic requirement.