Thomas Rupp

• Associate Professor (Human Movement Sciences)
• Professor (Associate) at University Savoie Mont Blanc, Chambéry, France

The aim of this study was to assess the effects of oxygen availability (normoxia vs. hypoxia), muscle mass and exercise type on pulse oxygen saturation, and quadriceps muscle oxygenation during repeated sprint exercises. Sixteen healthy participants completed 5 × ${\times} $ 12 s sprints (21 s rest). This sprint‐like exercise was performed under tw...

We compared neuromuscular fatigue induced by cycling at a fixed perceived effort in normoxic condition (NOR) and three purported hypoxia modalities: systemic hypoxia (SyH, FiO2 = 0.13), blood flow restriction (BFR, 50% arterial occlusion pressure) and airflow restriction mask (ARM, calibrated to ~3500 m). Seventeen healthy young participants cycled...

Purpose We examined how heat exposure affects muscle and cerebral oxygenation kinetics using statistical parametric mapping (SPM) during repeated treadmill sprints. Methods Eleven recreationally active males performed three sets of five 5-s sprints with 25 s of recovery and 3 min between sets in hot (38 °C) and temperate (25 °C) conditions. Contin...

Introduction: Neurovascular damage is one the main causes of morbidity and mortality in adults with sickle cell disease (SCD). This vulnerability is partly explained by chronic anemia and hemolysis, leading to endothelial dysfunction that can be associated with an impairment of cerebral vaso-reactivity. Near Infrared Spectroscopy (NIRS) has emerged...

Purpose Both cognitive motor dual-tasks (CMDT) protocols and hypoxic environments have been associated with significant impairments in cognitive and physical performance. We aimed to determine the effects of hypoxia on cognitive performance and neuromuscular fatigue during a highly physically demanding CMDT. Methods Fifteen young adults completed...

Background: Cerebral vasculopathy can induce chronic cerebral hypoperfusion leading to stroke in patients with sickle cell disease (SCD) and is treated by blood exchange transfusion (BET). However, no prospective clinical study has demonstrated the benefit of BET in adults with SCD and cerebral vasculopathy. Near Infrared Spectroscopy (NIRS) is a...

Purpose: Hypoxia is one major environmental factor, supposed to mediate central motor command as well as afferent feedbacks at rest and during exercise. By using a comparison of normobaric (NH) and hypobaric (HH) hypoxia with the same ambient pressure in oxygen, we examined the potential differences on the cerebrovascular and muscular regulation in...

Purpose: The aim of the present study was to assess left ventricular (LV) morphological and regional functional adaptations in backs and forwards elite rugby union (RU) players. Methods: Thirty-nine elite male RU players and twenty sedentary controls have been examined using resting echocardiography. RU players were divided into two groups, forw...

Purpose Repeated sprint ability is an integral component of team sports. This study aimed to evaluate fatigability development and its aetiology during and immediately after a cycle repeated sprint exercise performed until a given fatigability threshold. Methods On an innovative cycle ergometer, 16 healthy males completed an RSE (10-s sprint/28-s...

Purpose: While the physiological determinants of road running have been widely studied, there is a lack of research in trail-running racing performance. The aim of our study was to determine the physiological predictors of trail-running performance in races of different distances in similar terrain and weather conditions. Methods: Seventy-five t...

Purpose: Despite potential severe cardiac side effects, anabolic androgenic steroids (AAS) are increasingly used by strength athletes. However, previous echocardiographic studies focused on the left ventricular strains (LV) but did not assess LV twist and untwist mechanics. Moreover, LA function has been often neglected, and its stiffness, an impo...

Background: After anterior cruciate ligament reconstruction (ACLR), quadriceps strength must be maximized as early as possible. Objectives: We tested whether local vibration training (LVT) during the early post-ACLR period (i.e., ∼10 weeks) could improve strength recovery. Methods: This was a multicentric, open, parallel-group, randomized control...

The goal of this study was to analyse the effects of ground technicity on cardio‐respiratory and biomechanical responses during uphill running. Ten experienced male trail‐runners ran ∼10.5 min at racing pace on two trails with different (high and low) a priori technicity levels. These two runs were replicated (same slope, velocity, and distance) in...

The rise in oxygen consumption during the transition from rest to exercise is faster in those who are endurance-trained than those who have sedentary lifestyles, partly due to a more efficient cardiac response. However, data regarding this acute cardiac response in trained individuals are limited to heart rate (HR), stroke volume and cardiac output...

Purpose: Positive expiratory pressure (PEP) breathing has been shown to increase arterial oxygenation during acute hypoxic exposure but the underlying mechanisms and consequences on symptoms during prolonged high-altitude exposure remain to be elucidated. Methods: Twenty-four males (41 ± 16 years) were investigated, at sea level and at 5,085 m afte...

Background: Left ventricular (LV) remodeling, characterized by increased LV hypertrophy and depressed function, is observed in strength-trained athletes who use anabolic-androgenic steroids (AAS). Previous studies reported an increase in cardiac fibrosis in these athletes, which could promote intraventricular dyssynchrony. In this context, this st...

PurposeLower limbs’ neuromuscular force capabilities can only be determined during single sprints if the test provides a good fit of the data in the torque-velocity (T–V) and power-velocity (P–V) relationships. This study compared the goodness of fit of single sprints performed against traditional (7.5% of the body mass) vs. optimal load (calculate...

Introduction With millions of Europeans engaged in fitness club, strength training (ST) represents a widespread physical activity. At heart level, ST induces a concentric myocardial hypertrophy generally associated with a normal resting myocardial function. However, effect of ST have been described in men only, and whether women have similar cardia...

Fatigue‐related mechanisms induced by low‐intensity prolonged contraction in lower‐limb muscles are currently unknown. This study investigated central fatigue kinetics in the knee extensors during a low‐intensity sustained isometric contraction. Eleven subjects sustained a 10% maximal voluntary contraction (MVC) until task failure (TF) with neuromu...

Introduction: The understanding of fatigue in hypoxia is limited due to: lack of control in arterial saturation, different exercise intensities and hypoxia levels, lag time between exercise cessation and fatigue evaluation. We aimed at evaluating fatigue during cycling and immediately after exhaustion in normoxia, moderate and severe hypoxia at rel...

New findings: What is the central question of this study? Impairment and subsequent improvement in cerebral oxygenation during acute and prolonged exposure to high altitude affects exercise performance. However, this study innovates by investigating the effect of acute and prolonged high-altitude exposure on cerebral hemodynamics during a submaxim...

Sickle cell disease (SCD) is a genetic hemoglobinopathy leading to 2 major clinical manifestations: severe chronic hemolytic anemia and iterative vaso-occlusive crises. SCD is also accompanied by profound muscle microvascular remodeling. The beneficial effects of endurance training on microvasculature are widely known. The aim of this study was to...

Aims: Positive expiratory pressure (PEP) has been shown to limit hypoxia-induced reduction in arterial oxygen saturation but its effectiveness on systemic and cerebral adaptations depending on the type of hypoxic exposure (normobaric, NH vs. hypobaric, HH) remains unknown. Methods: Thirteen healthy volunteers completed three randomized sessions...

Purpose: Although strenuous exercise may expose sickle cell disease (SCD) patients to risks of vaso-occlusive crisis, evidence suggests that regular endurance exercise may be beneficial. This study aimed to test (i) the safety and usefulness of a submaximal incremental exercise in evaluating physical ability of SCD patients and identify a marker f...

Lower limbs muscle force capabilities can be determined during all-out sprints, but the method is accurate only if the testing protocol provides a good fit of the data in the torque-velocity (T-V) and power-velocity (P-V) relationship curves. This study compared the goodness of fit from single all-out sprints performed against the traditional (TRAD...

Fatigue may be defined as a progressive decline in maximal-force generating capacities and can occur although the target force can still be maintained (Zijdewind et al. 1998). Fatigue may arise in daily life activities when postural muscles are often involved over long periods of low-intensity contractions. To date, most studies have examined fatig...

Purpose This study aimed to determine the effects of hypoxia and/or blood flow restriction (BFR) on an arm-cycling repeated sprint ability test (aRSA) and its impact on elbow flexor neuromuscular function. Methods Fourteen volunteers performed an aRSA (10 s sprint/20 s recovery) to exhaustion in four randomized conditions: normoxia (NOR), normoxia...

Introduction L’atteinte vasculaire cérébrale sténosante dans la drépanocytose représente une des complications les plus graves, responsable d’accidents vasculaires cérébraux (AVC). La prévention de ces AVC repose sur la réalisation d’échanges transfusionnels (ET) au long cours. Cependant aucune évaluation n’a été faite à ce jour sur le bénéfice de...

Objectives: The purpose of this study was to investigate the acute vascular and oxygenation responses to repeated sprint exercise during arm cycling with either blood flow restriction (BFR) or systemic hypoxia alone or in combination. Design: The study design was a single-blinded repeated-measures assessment of four conditions with two levels of...

Purpose: At the onset of physical exercise, oxygen (O2) transport adapts to meet the working muscle O2 demands. Cardiac output abruptly increases through the concomitant changes of heart rate and stroke volume (SV), which is conditioned by the left ventricular (LV) function. The purpose of this study was to investigate the contribution of many LV...

INTRODUCTION: Fatigue may be defined as a progressive decline in maximal-force generating capacities and can occur although the target force can still be maintained (Zijdewind et al. 1998). Fatigue may arise in daily life activities when postural muscles are often involved over long periods of low-intensity contractions. To date, most studies have...

New findings: What is the central question of this study? This study is the first investigating the effects of high-altitude trekking on biventricular mechanics including measurements of left ventricular (LV) subendocardial and subepicardial function. What is the main finding and its importance? We provide new evidence that an increased contractil...

Purpose The adaptations induced by endurance training on the neuromuscular function remain under investigation and, for methodological reasons, unclear. This study investigates the effects of cycling training on neuromuscular fatigue and its peripheral contribution measured during and immediately after cycling exercise. Methods Fourteen healthy me...

This study investigated the effects of 9-week endurance cycling training on central fatigability and corticomotor excitability of the locomotor muscles. Fourteen healthy participants undertook three incremental fatiguing cycling tests to volitional exhaustion (EXH): (i) before training (PRE), (ii) after training at the same absolute power output as...

Background: Exercise could be a triggering factor for vaso-occlusive crises in patients with sickle-cell disease. We aimed to investigate whether a patient-adapted training programme of moderate endurance exercise could be safe and beneficial for patients with sickle-cell disease. Methods: We did a multicentre, prospective, open-label, randomised c...

INTRODUCTION: The magnitude and etiology of fatigue following whole-body exercises at different altitudes remain equivocal owing to i) the actual degree of hypoxemia (arterial saturation, SpO2) achieved by the subjects, ii) the consideration of relative vs absolute workloads and iii) the lag time between exercise cessation and fatigue evaluation, w...

Introduction La drépanocytose est une maladie génétique liée à une mutation de la bêta globine, caractérisée par une hémolyse chronique et une dysfonction vasculaire. L’atteinte vasculaire cérébrale sténosante représente une des complications les plus graves, responsable d’accidents vasculaires cérébraux, dont la prévalence se situe entre 4 à 13 %...

B Gellen and L Messonnier, and L Feasson and P Bartolucci equally contributed to this work Introduction Sickle cell disease (SCD) is the most common inherited disease worldwide. Because favoring the risk of vaso-occlusive crises (VOC), SCD patients are banned from strenuous exercise. We hypothesized that a well-controlled moderate-intensity enduran...

Abstract Normobaric hypoxia (NH) is used as a surrogate for hypobaric hypoxia (HH). Recent studies reported physiological differences between NH and HH. Baroreflex sensitivity (BRS) decreases at altitude or following intense training. However, until now no study compared the acute and chronic changes of BRS in NH vs. HH. First, BRS was assessed in...

Introduction : La drépanocytose est une hémoglobinopathie génétique ayant pour conséquences deux manifestations cliniques majeures : une anémie hémolytique chronique sévère et des crises vaso-occlusives itératives. Récemment, nous avons mis en évidence que la drépanocytose s’accompagnait d’un remodelage profond du tissu musculaire, contribuant à l’...

Objective: With an aging population and the increasing prevalence of heart failure with preserved ejection fraction, developing strategies to prevent diastolic dysfunction is crucial. Regular endurance training has been suggested to be one such strategy. However, the underlying mechanisms of training, including the effect on left ventricular (LV)...

Introduction : La drépanocytose est une hémoglobinopathie génétique ayant pour conséquences deux manifestations cliniques majeures : une anémie hémolytique chronique sévère et des crises vaso-occlusives itératives. Récemment, nous avons mis en évidence que la drépanocytose s’accompagnait d’un remodelage profond et délétère du tissu musculaire, cont...

Purpose: Currently, cortical voluntary activation (VATMS) is assessed by superimposing transcranial magnetic stimulation (TMS) on a maximal voluntary contraction (MVC), 75% MVC and 50% MVC, each contraction being interspersed with 5-10 s of relaxation. Here, we assessed whether this traditional approach (TRADI) underestimates central fatigue due t...

Purpose: While acute hypoxic exposure enhances exercise-induced central fatigue and can alter corticospinal excitability and inhibition, the effect of prolonged hypoxic exposure on these parameters remains to be clarified. We hypothesized that 5 days of altitude exposure would (i) normalize exercise-induced supraspinal fatigue during isolated musc...

Introduction: The aim of this study was to determine whether calf compression sleeves (CS) affects physiological and biomechanical parameters, exercise performance, and perceived sensations of muscle fatigue, pain and soreness during prolonged (~2 h 30 min) outdoor trail running. Methods: Fourteen healthy trained males took part in a randomized, cr...

Aims: The aim of this study was to analyse the underlying mechanisms of left and right ventricular (LV and RV) functional alterations during several days in high-altitude hypoxia. Methods and results: Resting evaluations of LV and RV function and mechanics were assessed by Speckle Tracking Echocardiography on 11 subjects at sea level (SLPRE), 3...

Purpose: Prolonged cycling exercise performance in normoxia is limited due to both peripheral and central neuromuscular impairments. It has been reported that cerebral perturbations are greater during short-duration exercise in hypoxia compared to normoxia. The purpose of this study was to test the hypothesis that central deficits are accentuated...

Objective: Hypoxic exposure in healthy subjects can induce acute mountain sickness including headache, lethargy, cerebral dysfunction, and substantial cerebral structural alterations which, in worst case, can lead to potentially fatal high altitude cerebral edema. Within this context, the relationships between high altitude-induced cerebral edema,...

Introduction: Calf compression sleeves (CS) are increasingly used in off-road exercises, however, no analyses have been conducted so far on the impact of wearing CS on simultaneous physiological and biomechanical adaptations during prolonged (>2 h) outdoor trail running. The aim of this study was therefore to analyse whether CS may modify muscle ox...

Ultramarathon runners are exposed to a high number of impact shocks and to severe neuromuscular fatigue. Runners may manage mechanical stress and muscle fatigue by changing their running kinematics. Our purposes were to study (i) the effects of a 110-km mountain ultramarathon (MUM) on tibial shock acceleration and lower limb kinematics, and (ii) wh...

Study objectives: Hypoxia is known to generate sleep-disordered breathing but there is a debate about the pathophysiological responses to two different types of hypoxic exposure: normobaric hypoxia (NH) and hypobaric hypoxia (HH), which have never been directly compared. Our aim was to compare sleep disorders induced by these two types of altitude...

PURPOSE: Slight physiological differences between acute exposure in normobaric hypoxia (NH) and hypobaric hypoxia (HH) have been reported. Taken together, these differences suggest different physiological responses to hypoxic exposure to a simulated altitude (NH) versus a terrestrial altitude (HH). For this purpose, in the present study, we aimed t...

Background To get insight into the underlying mechanisms of changes in left ventricular (LV) systolic and diastolic functions during several days in high-altitude hypoxia. Methods and results Resting evaluations of LV function and mechanics by 2D-strain echocardiography were performed on eleven subjects at sea level (SLPRE), 3h±2h after helicopter...

During the transition from rest to exercise, heart rate (HR) immediately increase to provide a sufficient O2 delivery to active muscle. This adaptation of HR induces a dramatically decrease of left ventricular (LV) filling time, that requires a very fast adaptation of the LV diastolic function to maintain LV filling. Diastolic function depends on m...

Means, standard deviations (SD), coefficients of variation (%CV), 95% confidence intervals (95% CI + and 95% CI -) and Cohen’s d coefficients for plantar flexors neuromuscular variables. (DOCX)

Means, standard deviations (SD), coefficients of variation (%CV), 95% confidence intervals (95% CI + and 95% CI -) and Cohen’s d coefficients for knee extensors neuromuscular variables. (DOCX)

Means, standard deviations (SD), coefficients of variation (%CV), 95% confidence intervals (95% CI + and 95% CI -) and Cohen’s d coefficients for impact-related variables. (DOCX)

Means, standard deviations (SD), coefficients of variation (%CV), 95% confidence intervals (95% CI + and 95% CI -) and Cohen’s d coefficients for kinematics. (DOCX)

Study objectives: To evaluate changes in muscle and cerebral oxygenation during intermittent hypoxia (IH). Methods: Fifteen healthy subjects were exposed to 45-min IH (2-min cycles). Arterial blood oxygen saturation (SpO2), prefrontal cortex and brachial biceps muscle oxygenation (assessed by near-infrared spectroscopy), heart rate, and ventilat...

AIMS: Investigations on the cardiac consequences of mountain ultra-marathon (MUM) > 100h are lacking. The present study assessed the progressive cardiac responses during the world's most challenging MUM (Tor des Geants; Italy; 330km; 24000m of positive elevation change). METHODS AND RESULTS: Resting echocardiographic evaluation of morphology, funct...

Introduction: It is well established that exposure to hypoxia can alter prooxidant/antioxidant balance. However, the effect of pressure per se on hypoxiainduced oxidative stress is not well established. Accordingly we investigated the effect of 10-hour exposure to either normobaric normoxic confinement (NN), simulated altitude (normobaric hypoxia;...

Transcranial magnetic stimulation (TMS) of the motor cortex during voluntary contractions elicits electrophysiological and mechanical responses in the target muscle. The effect of different TMS intensities on exercise-induced changes in TMS-elicited variables is unknown, impairing data interpretation. This study aimed to investigate TMS intensity e...

Factors underlying the amplitude of exercise performance reduction at altitude and the development of high-altitude illnesses are not completely understood. To better describe these mechanisms, we assessed cardiorespiratory and tissue oxygenation responses to hypoxia in elite high-altitude climbers. Eleven high-altitude climbers were matched with 1...

The central nervous system can play a critical role in limiting exercise performance during hypoxic conditions. Hypocapnia, which is associated with hypoxia-induced hyperventilation, may affect cerebral perfusion. We hypothesized that CO2 clamping during hypoxic isometric knee extensions would improve cerebral oxygenation and reduce central fatigue...

Hypoxia exposure in human can be obtained using two different type of paradigm: either hypobaric hypoxia (HH) or normobaric hypoxia (NH). It was believed that the decrease in the partial pressure of inspired oxygen (PiO2) was the unique modulator of the physiological responses to hypoxia. However, a growing body of evidence suggest that the differe...

In cardiac diseases or healthy aging, the oxygen uptake kinetics are limited by muscle O2 delivery, which directly depends of the response of the cardiorespiratory system at the onset of exercise. However, data regarding cardiac adaptation during the transition from rest to exercise are limited to heart rate, stroke volume and cardiac output. Today...

Introduction: Recently research has focused on the potential differences between normobaric hypoxia (NH) and hypobaric hypoxia (HH). Slight physiological differences between acute exposure in NH and HH have been reported. Taken together, these differences suggest different physiological responses to hypoxic exposure in simulated (NH) versus real al...

The automatic detection of sleep apnea episodes, without the need of polysomnography and outside a clinical facility, could help facilitate the diagnosis of this disorder. In this work, features to detect sleep apnea events were computed from respiration and electrocardiogram recordings acquired with a wearable smart-shirt. First, a classical schem...

This study investigated the effects of acute hypoxia on spinal reflexes and soleus muscle function after a sustained contraction of the plantar flexors at 40 % of maximal voluntary isometric contraction (MVC). Fifteen males (age 25.3 ± 0.9 year) performed the fatigue task at two different inspired O2 fractions (FiO2 = 0.21/0.11) in a randomized and...

Purpose: Despite interest in the possibility of females outperforming males in ultraendurance sporting events, little is known about the sex differences in fatigue during prolonged locomotor exercise. This study investigated possible sex differences in central and peripheral fatigue in the knee extensors and plantar flexors resulting from a 110-km...

The present study assessed the isolated and synergetic effects of hypoxic exposure and prolonged exercise on cerebral volume and subedema and symptoms of acute mountain sickness (AMS). Twelve healthy males performed three semirandomized blinded 11-hour sessions with (1) an inspiratory oxygen fraction (FiO2) of 12% and 4-hour cycling, (2) FiO2=21% a...

Background: The aim of this study was to test the effect of endurance training on the age-related changes of left ventricular (LV) twist-untwist mechanics. Aging has been shown to induce a decline of diastolic function and more recently an impairment of twist-untwist mechanics, which constitutes an important factor for early diastolic suction and...

New Findings What is the central question of this study? Progressive development of the supraspinal component of central fatigue and increases in corticospinal excitability and inhibition have been demonstrated during fatiguing contractions of the elbow flexors. However, the kinetics of mechanical and EMG responses induced by transcranial magnetic...

Transcranial magnetic stimulation (TMS) is a widely-used investigative technique in motor cortical evaluation. Recently, there has been a surge in TMS studies evaluating lower-limb fatigue. TMS intensity of 120-130% resting motor threshold (RMT) and 120% active motor threshold (AMT) and TMS intensity determined using stimulus-response curves during...

Maximal central motor drive is known to decrease during prolonged exercise although it remains to be determined whether a supraspinal deficit exists, and if so, when it appears. The purpose of this study was to evaluate corticospinal excitability and muscle voluntary activation before, during and after a 4-h cycling exercise. Ten healthy subjects p...

Introduction: Positive end-expiratory pressure (PEEP) is commonly used in critical care medicine to improve gas exchange. Altitude sickness is associated with exaggerated reduction in arterial oxygenation. We assessed the effect of PEEP and pursed lips breathing (PLB) on arterial and tissue oxygenation under normobaric and hypobaric hypoxic condit...

Objective: The aim of the study is to characterize left ventricular (LV) myocardial mechanics in adults with metabolic syndrome (MetS), and elucidate the effects of multiple risk-factors on myocardial function using speckle tracking echocardiography (STE); a more sensitive method than conventional echocardiography for detecting subclinical myocard...

Introduction “Real altitude” (e.g. hypobaric hypoxia) has been reported to impair sleep and induce sleep disordered breathing (SDB). It is however not clear whether for the same ambient Oxygen pressure (PO2) “simulated altitude” in a hypoxic chamber (e.g. normobaric hypoxia;) generates similar sleep alterations. Materials and methods Full polysomn...

The well-established central deficit in ultra-endurance running races is not understood. The use of transcranial magnetic stimulation (TMS) in parallel with peripheral nerve stimulation provides insight into the source of these central changes. The aims of this study were to determine the presence and magnitude of voluntary activation deficits, esp...

Objective: Recent findings indicated silent incipient myocardial dysfunction in juvenile obesity despite normal global cardiac function. The present study investigated whether lifestyle intervention is able to favorably impact these obesity-related myocardial abnormalities and whether improvements are related to changes in insulin resistance and c...