Laurent Schmitt

Laurent Schmitt
National Ski-Nordic Centre, Premanon, France · Research, Performance

PhD

About

73
Publications
44,970
Reads
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2,462
Citations
Additional affiliations
September 2013 - present
University of Lausanne
Position
  • Research Associate
September 1984 - present
National Ski-Nordic Centre, Premanon, France
Position
  • Head of Department
Description
  • National training and research centre for the french national teams in nordic-combined, biathlon, cross-country skiing.

Publications

Publications (73)
Article
Full-text available
Easy-to-use and accurate heart rate variability (HRV) assessments are essential in athletes’ follow-up, but artifacts may lead to erroneous analysis. Artifact detection and correction are the purpose of extensive literature and implemented in dedicated analysis programs. However, the effects of number and/or magnitude of artifacts on various time-...
Article
Purpose: To present training load (TL) and heart-rate variability (HRV) in an elite sprinter monitored before, during, and after a COVID-19 infection until successful return to performance. Methods: TL, subjective morning fatigue (MF), and supine HRV were monitored during a 12-week period. Results: During a high-TL period (training camp), MF a...
Article
Full-text available
Purpose: This study aimed to investigate the differences between normobaric (NH) and hypobaric hypoxia (HH) on supine heart rate variability (HRV) during a 24-h exposure. We hypothesized a greater decrease in parasympathetic-related parameters in HH than in NH. Methods: A pooling of original data from forty-one healthy lowland trained men was analy...
Article
High-intensity training sessions are known to alter cardiac autonomic modulation. The purpose of this study was to compare the effects of whole-body cryotherapy, contrast water therapy and passive recovery on the time course of cardiac autonomic markers following a standardized HIT session. Eleven runners completed a high intensity session followed...
Article
Full-text available
PurposeTo examine physiological and technical responses to repeated-sprint training in normobaric hypoxia at ∼3,000 m (RSH, n = 11) or in normoxia (RSN, n = 11) compared to a control group (CON, n = 8) in well-trained tennis players. Participants were 28.8 ± 5.9 years old without any previous experience of training in hypoxia.Methods In addition to...
Article
Full-text available
Introduction Strict lockdown rules were imposed to the French population from 17 March to 11 May 2020, which may result in limited possibilities of physical activity, modified psychological and health states. This report is focused on HRV parameters kinetics before, during and after this lockdown period. Methods 95 participants were included in th...
Article
Full-text available
Purpose: To report the changes in the training characteristics, performance, and heart-rate variability (HRV) of the world's most successful male biathlete of the last decade. Method: During the analyzed 11-year (2009-2019) period, the participant won 7 big crystal globes, corresponding to the winner of the International Biathlon Union World Cup...
Article
Heart rate variability (HRV) is an analysis of milliseconds variations in intervals between heartbeats and has become an increasingly used tool for clinical investigation of fatigue, especially in athletes. Eliciting an indirect index of the autonomic nervous system regulation on the heart rate, HRV correlates with different fatigue states and appe...
Preprint
Full-text available
Introduction: Strict lockdown rules were imposed to the French population from 17 March to 11 May 2020, which may result in limited possibilities of physical activity, modified psychological and health states. This report is focused on HRV parameters kinetics before, during and after this lockdown period. Methods: 95 participants were included in t...
Chapter
Introduction Le succès au tennis dépend largement des qualités mentales et technico-tactiques du joueur mais requiert également une interaction complexe entre les qualités physiques (force, vitesse, coordination, souplesse, endurance, agilité) et les systèmes de fourniture d’énergie (aérobie et anaérobie) (Fernandez et al., 2006). Afin de maximise...
Article
Full-text available
This study examined the physiological, physical and technical responses to repeated-sprint training in normobaric hypoxia [RSH, inspired fraction of oxygen (FiO2) 14.5%] vs. normoxia (RSN, FiO2 20.9%). Within 12 days, eighteen well-trained tennis players (RSH, n = 9 vs. RSN, n = 9) completed five specific repeated-sprint sessions which consisted of...
Article
Full-text available
Purpose: To analyze the effects of different training strategies (i.e., mainly intensity distribution) during living high – training low (LHTL) between elite cross-country skiers and Nordic-combined athletes. Methods: 12 cross-country skiers (XC) (7 men, 5 women), and 8 male Nordic combined (NC) of the French national teams were monitored during 15...
Article
Purpose: To compare technical and physiological responses between junior and professional female players during an incremental field test to exhaustion specific to tennis (TEST). Methods: Twenty-seven female players (n=14 and 13 for juniors and professionals, respectively) completed an incremental field test to exhaustion specific to tennis, whi...
Article
The aim of this case study was to investigate the effects of a shock microcycle of repeated-sprint training in hypoxia (RSH) on physical fitness and tennis performance. One rookie professional tennis player performed repeated-sprint ability (RSA) and Yo-Yo Intermittent Recovery level 2 (YYIR2) tests before and after (+3 days and +21 days) six sessi...
Article
We aimed to analyse the relationship between training load/intensity and different heart rate variability (HRV) fatigue patterns in 57 elite Nordic-skiers. 1063 HRV tests were performed during 5 years. R-R intervals were recorded in resting supine (SU) and standing (ST) positions. Heart rate, low (LF), high (HF) frequency powers of HRV were determi...
Article
Full-text available
Purpose: To analyze if live high-train low (LHTL) effectiveness is improved when daily training is guided by heart rate variability (HRV). Methods: Twenty-four elite Nordic skiers took part in a 15-day LHTL study and were randomized into a HRV-guided training hypoxic group (H-HRV, n = 9, sleeping in normobaric hypoxia, FiO2 = 15.0%) and two pred...
Article
Si bien el análisis del rendimiento tenístico subraya la relación entre los parámetros físicos y técnicos, los enfoques científicos o de entrenamiento suelen dejar de lado estos dos aspectos en la misma sesión de entrenamiento. La efectividad de combinar los factores físicos y técnicos se ve reforzada por los nuevos resultados disponibles gracias a...
Article
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Although tennis performance analysis underlines the relationship between physical and technical parameters, scientific or coaching approaches often neglect to develop these two aspects in the same training session. The effectiveness of combining physical and technical factors is reinforced by new results made available through the optimization of n...
Article
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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...
Article
It has been proposed that athletes with high initial values of hemoglobin mass (Hbmass ) will have a lower Hbmass increase in response to 'live high-train low' (LHTL) altitude training. To verify this assumption, the relationship between initial absolute and relative Hbmass values and their respective Hbmass increase following LHTL in male enduranc...
Article
Full-text available
Heart rate variability (HRV) is non-invasive and commonly used for monitoring responses to training loads, fitness, or overreaching in athletes. Yet, the recording duration for a series of RR-intervals varies from 1 to 15 min in the literature. The aim of the present work was to assess the minimum record duration to obtain reliable HRV results. RR-...
Article
Purpose: To compare individual hemoglobin mass (Hbmass) changes following a live high-train low (LHTL) altitude training camp under either normobaric hypoxia (NH) or hypobaric hypoxia (HH) conditions in endurance athletes. Methods: In a crossover design with a one-year washout, 15 male triathletes randomly performed two 18-d LHTL training camps...
Article
Full-text available
Purpose: We investigated technical and physiological responses along with their relationships during an incremental field test to exhaustion specific to tennis (TEST) in elite players. Methods: Twenty male elite tennis players completed TEST, which consisted of hitting alternatively forehand and backhand strokes at increasing ball frequency (bal...
Article
Full-text available
Although assessment of the technical, physical and physiological qualities required for performance optimisation is complex in tennis, it is nonetheless essential to training planning. While physical goals are often dissociated from technical ones, we argue that a recently validated stress test specific to tennis, known as "TEST" (Brechbuhl, Girard...
Article
Full-text available
TEST D’EFFORT SPÉCIFIQUE AU TENNIS (TEST) : ÉTUDE DE CAS D’UN JOUEUR ÉLITE. Cyril Brechbuhl (FRA, Fédération Française de Tennis, Doctorant UNIL), Olivier Girard (FRA, PhD, Aspetar), Grégoire Millet (FRA, PhD, UNIL), Laurent Schmitt (FRA, PhD, CNSN Prémanon) RÉSUMÉ L’évaluation des qualités techniques, physiques et physiologiques requises pour l'o...
Article
Full-text available
Saugy, Jonas J., Laurent Schmitt, Sibylle Fallet, Raphael Faiss, Jean-Marc Vesin, Mattia Bertschi, Raphael Heinzer, and Gregoire P. Millet. Sleep disordered breathing during live high-train low in normobaric versus hypobaric hypoxia. High Alt Med Biol. 16:000-000, 2016.-The present study aimed to compare sleep disordered breathing during live high-...
Article
PURPOSE: To compare hemoglobin mass (Hbmass) changes during an 18-d live high-train low (LHTL) altitude training camp in normobaric hypoxia (NH) and hypobaric hypoxia (HH). METHODS: Twenty-eight well-trained male triathletes were split into three groups (NH: n = 10, HH: n = 11, control [CON]: n = 7) and participated in an 18-d LHTL camp. NH and HH...
Article
Full-text available
Purpose: We investigated the changes in physiological and performance parameters after a Live High-Train Low (LHTL) altitude camp in normobaric (NH) or hypobaric hypoxia (HH) to reproduce the actual training practices of endurance athletes using a crossover-designed study. Methods: Well-trained triathletes (n = 16) were split into two groups and...
Article
Full-text available
Purpose: We aimed to a) introduce a new Test to Exhaustion Specific to Tennis (TEST) and compare performance (test duration) and physiological responses to those obtained during the 20-m multistage shuttle test (MSST), and b) determine to which extent those variables correlate with performance level (tennis competitive ranking) for both test proce...
Article
Full-text available
Conclusion: both the accuracy and the reliability of this new ball machine appear satisfying enough for field testing and training. Key pointsThe reliability and accuracy of a new ball machine named 'Hightof' were assessed.The impact point was reproducible and similar on the right and left sides (±0.63 m).The precision was constant and did not inc...
Article
Full-text available
Among the tools proposed to assess the athlete's “fatigue,” the analysis of heart rate variability (HRV) provides an indirect evaluation of the settings of autonomic control of heart activity. HRV analysis is performed through assessment of time-domain indices, the square root of the mean of the sum of the squares of differences between adjacent no...
Article
Full-text available
“Live High-Train Low” (LHTL) training can alter oxidative status of athletes. This study compared prooxidant/antioxidant balance responses following two LHTL protocols of the same duration and at the same living altitude of 2250 m in either normobaric (NH) or hypobaric (HH) hypoxia. Twenty-four well-trained triathletes underwent the following two 1...
Article
This study investigated changes in heart rate variability (HRV) in elite Nordic-skiers to characterize different types of "fatigue" in 27 men and 30 women surveyed from 2004 to 2008. R-R intervals were recorded at rest during 8 min supine (SU) followed by 7 min standing (ST). HRV parameters analysed were powers of low (LF), high (HF) frequencies, (...
Article
Full-text available
The inspired fraction of oxygen (F i O 2) for the normobaric hypoxic condition was incorrectly reported to be 15.8 ± 0.8%. The correct F i O 2 value for the NH condition is 17.9 ± 0.2% and the correct inspired pressure of oxygen (P i O 2) values were 111.1 ± 1.1 vs 111.5 ± 1.0 mmHg in nor-mobaric and hypobaric hypoxia, respectively. The authors wis...
Article
Full-text available
We investigated the changes in both performance and selected physiological parameters following a Live High-Train Low (LHTL) altitude camp in either normobaric hypoxia (NH) or hypobaric hypoxia (HH) replicating current "real" practices of endurance athletes. Well-trained triathletes were split into two groups (NH, n = 14 and HH, n = 13) and complet...
Article
Purpose: We analyzed heart rate variability (HRV) to detect alterations in autonomic function that may be associated with functional overreaching (F-OR) in endurance athletes. Methods: Twenty one trained male triathletes were randomly assigned to either intensified training (n=13) or normal training (n=8) groups during 5 weeks. HRV measures were t...
Article
Full-text available
We analyzed HR variability (HRV) to detect alterations in autonomic function that may be associated with functional overreaching (F-OR) in endurance athletes. Twenty-one trained male triathletes were randomly assigned to either intensified training (n = 13) or normal training (n = 8) groups during 5 wk. HRV measures were taken daily during a 1-wk m...
Poster
The aim of this research is to compare the evolution of anthropometric variables and body composition in 2 groups of athletes during a stay at altitude, living upstairs - training below (LHTL), a group lived in rooms of normobaric hypoxia (HN) and the another in hypobaric hypoxia (HH).
Article
Full-text available
This longitudinal study aimed at comparing heart rate variability (HRV) in elite athletes identified either in 'fatigue' or in 'no-fatigue' state in 'real life' conditions. 57 elite Nordic-skiers were surveyed over 4 years. R-R intervals were recorded supine (SU) and standing (ST). A fatigue state was quoted with a validated questionnaire. A multil...
Data
Questionnaire of the French Society of Sport Medicine (QSFMS). (DOC)
Article
Full-text available
to the editor: To explain an ineffective live high-train low (LHTL) in normobaric hypoxia (e.g., where the athletes slept in hypoxic chamber), Siebenman et al. ([4][1]) suggested that the recommended 16 h/day of room confinement may lead to a reduction in plasma volume: 13.8% and 20.1% in the
Article
Full-text available
New methods and devices for pursuing performance enhancement through altitude training were developed in Scandinavia and the USA in the early 1990s. At present, several forms of hypoxic training and/or altitude exposure exist: traditional ‘live high-train high’ (LHTH), contemporary ‘live high-train low’ (LHTL), intermittent hypoxic exposure during...
Article
Full-text available
It has been shown that the antioxidant status was altered by the "live high-train low" (LHTL) method, however, no information is available regarding the antioxidant restoration during the recovery period. We tested the hypothesis that the antioxidant status is impaired by 18 days LHTL in elite athletes and remained altered after 14 days of recovery...
Article
The aim of this study was to determine the response of blood markers to acute hypoxia in high-level endurance athletes before training based on "living high-training low" model. Thirty endurance athletes performed a hypoxic cycling test and spent 3 h at rest in a simulated altitude of 3,000 m. At the end of the hypoxic cycling test, the quantity of...
Article
Full-text available
We investigated the strength of the association between oxidative stress, hypoxia inducible factor 1 (HIF-1 alpha) and acute hypoxic ventilatory response (AHVR) after hypoxic training in elite runners. Six elite runners were submitted to 18-day of "living high-training low" (LHTL) and six performed the same training in normoxia. AHVR was measured d...
Article
We investigated whether acute hypoxic exposures could modify the pro-oxidant/antioxidant balance in elite endurance athletes, known to have efficient antioxidant status. Forty-one elite athletes were subjected to two hypoxic tests: one at an altitude of 4 800 m during 10-min of mild exercise (4 800 m test) and the second at rest for 3 h at an altit...
Article
Full-text available
We previously demonstrated that acute exposure to hypoxia (3 h at 3000 m) increased oxidative stress markers. Thus, by using the 'living high-training low' (LHTL) method, we further hypothesized that intermittent hypoxia associated with endurance training alters the prooxidant/antioxidant balance. Twelve elite athletes from the Athletic French Fede...
Article
Opuntia ficus indica (OFI) has many physiological effects, but a relationship between OFI and heart-rate variability (HRV) has never been established. The aim of this study was to describe the effects of a diet supplement of OFI on HRV in athletes. The first day, heart rate (HR) was measured at rest in supine (SU) and standing (ST) positions to ana...
Article
Full-text available
Opuntia ficus indica (OFI) has many physiological effects, but a relationship between OFI and heart-rate variability (HRV) has never been established. The aim of this study was to describe the effects of a diet supplement of OFI on HRV in athletes. The first day, heart rate (HR) was measured at rest in supine (SU) and standing (ST) positions to ana...
Article
Full-text available
We analyzed the relationship between aerobic capacities and changes in heart rate variability (HRV) in Nordic-skiers during living high-training low (Hi-Lo). Eleven skiers trained for 18 days at 1200 m, sleeping at 1200 m (LL, n = 5) or in hypoxic rooms (HL, n = 6, 3 x 6 days at altitudes of 2500 - 3000 - 3500 m, 11 h . day (-1)). Measurements were...
Article
Altitude training is popular among athletes to augment oxygen delivery capabilities to tissues and to improve physical performance. Hypoxia inducible factor-1 (HIF-1) controls the expression of several genes' encoding involved in physiological responses towards reduced oxygen availability, in particular by increasing serum erythropoietin (EPO). It...
Article
Full-text available
The "living high-training low" model (Hi-Lo) may improve aerobic performance in athletes, and the main mechanism of this improvement is thought to be augmented erythropoiesis. A positive effect of Hi-Lo has been demonstrated previously by using altitudes of 2,000-3,000 m. Since the rate of erythropoiesis is altitude-dependent, we tested whether a h...
Article
Full-text available
This study tested the effects of “living high-training low” (Hi–Lo) on aerobic performance and economy of work in elite athletes. Forty endurance athletes (cross-country skiers, swimmers, runners) performed 13–18 consecutive days of training at 1,200 m altitude, by sleeping at 1,200 m (LL, n = 20) or in hypoxic rooms with 5–6 nights at 2,500 m foll...
Article
Full-text available
The “living high–training low” model (LHTL), i.e., training in normoxia but sleeping/living in hypoxia, is designed to improve the athletes performance. However, LHTL efficacy still remains controversial and also little is known about the duration of its potential benefit. This study tested whether LHTL enhances aerobic performance in athletes, and...
Article
Full-text available
Unlabelled: The aim of this study was to compare the effects of training at two different altitudes on heart rate variability (HRV) and performance in well-trained swimmers. Eight national-level male swimmers (age = 17.0 +/- 1.8 yrs, weight = 67.0 +/- 6.6 kg, height = 180.4 +/- 7.2 cm, V(O2max) = 60.4 +/- 4.0 ml.min(-1). kg(-1)) trained 17 days at...
Article
Full-text available
The effects of living and training have not been compared at different altitudes in well trained subjects. Nine international swimmers lived and trained for 13 days similarly at 1200 m (T1200) and 1850 m (T1850). The two altitude training periods were separated by six weeks of sea level training. Before and after each training trip, subjects perfor...
Article
The autonomic and cardiovascular adaptations to hypoxia are opposite to those resulting from aerobic training. We investigated (1) whether exposure to hypoxia in a live high-train low (LHTL) session limits the autonomic and cardiovascular adaptations to training, and (2) whether such interactions remain 15 days after the end of the LHTL. Eighteen n...
Article
Full-text available
The "living high-training low" (LHTL) model is frequently used to enhance aerobic performance. However, the clinical tolerance and acclimatization process to this intermittent exposure needs to be examined. Forty one athletes from three federations (cross-country skiers, n=11; swimmers, n=18; runners, n=12) separately performed a 13 to 18-day train...