Florence Riera | Université de Perpignan-Via Domitia (original) (raw)

Papers by Florence Riera

International Journal of Sports Medicine, 2016

This study investigated whether the combination of internal precooling (PC) and internal midcooli... more This study investigated whether the combination of internal precooling (PC) and internal midcooling (MC cooling during exercise) would enhance performance more than MC alone. 9 trained males completed two 30-km cycling trials in a hot and humid environment (WBGT: 29±0.7°C, 80±0.02% relative humidity). For 30 min before exercise, the subjects sat quietly and drank water at 23°C (MC) or 3°C (PC+MC). During the MC and PC+MC time trials, they drank an ice-slush/menthol beverage (i. e., 0.025% menthol). Trial time, gastrointestinal temperature (Tco ), heart rate (HR), rating of perceived exertion (RPE), thermal sensation (TS), and thermal comfort (TC) were assessed. Trial time was not significantly different (P>0.05) between MC and PC+MC (3 737±552 s and 3 815±455 s). Before exercise, Tco was lower with precooling (37.0±0.3°C; P<0.02). During exercise, no between-trial differences were noted for Tco, HR, RPE, TC or TS, but RPE was significantly lower with PC+MC in the latter stages (P<0.05). (1) Cold beverage intake before exercise did not improve the subsequent exercise performance with ice-slush/menthol beverage intake, and (2) despite no improvement in performance, RPE declined in the latter stages of exercise in the condition of PC+MC, suggesting that this combination might be beneficial for longer exercise.

Significant (P<0.05) differences are represented by letters (N: di... more Significant (P<0.05) differences are represented by letters (N: different from neutral, C: different from cold, I: different from Ice, NM: different from Neutral-Menthol, IM: different from Ice-Menthol, CM: different from Cold-Menthol, I/IM: different from both Ice and Ice-Menthol, I/NM/IM: different from Ice, Neutral-Menthol and Ice-Menthol, I/CM/IM: different from Ice, Cold-Menthol and Ice-Menthol).</p

Mean values are shown.</p

Mean values and SD are shown. * significantly different from Neutral (P</i&g... more Mean values and SD are shown. * significantly different from Neutral (P<0.01), † significantly different from Neutral-Menthol (P<0.01), and β significantly different from water Cold-Menthol (P<0.01).</p

Sports Medicine, 2020

Introduction Menthol topical application and mouth rinsing are ergogenic in hot environments, imp... more Introduction Menthol topical application and mouth rinsing are ergogenic in hot environments, improving performance and perception, with differing effects on body temperature regulation. Consequently, athletes and federations are beginning to explore the possible benefits to elite sport performance for the Tokyo 2021 Olympics, which will take place in hot (~ 31 °C), humid (70% RH) conditions. There is no clear consensus on safe and effective menthol use for athletes, practitioners, or researchers. The present study addressed this shortfall by producing expert-led consensus recommendations. Method Fourteen contributors were recruited following ethical approval. A three-step modified Delphi method was used for voting on 96 statements generated following literature consultation; 192 statements total (96/96 topical application/mouth rinsing). Round 1 contributors voted to “agree” or “disagree” with statements; 80% agreement was required to accept statements. In round 2, contributors vot...

Pflügers Archiv - European Journal of Physiology, 2007

Objective: The aim of this study is to review the existing indexes for quantifying the total musc... more Objective: The aim of this study is to review the existing indexes for quantifying the total muscle activity for muscle groups. Background: EMG has been used in ergonomics for many years with many approaches and techniques employed to solve different problems. Most previous studies used to detect surface EMG signals from several specific muscles, and present the electrical activity levels of muscles one by one. However, there are relatively few attempted to account the "total" muscular load of overall muscle groups. Method: Google scholar, ScienceDirect, Pubmed, and Springerlink were searched for studies describing total muscle activity. The methods of the existing research papers (subjects, measuring equipment, measurement position, measurement methods) and the research purposes (clinical, physical exercise, workplace design, health assessment etc.) were analyzed and summarized. Results: A total of 27 papers were eligible for this review study and the methods to quantity the "total EMG index" can be divided into 4, such as: (1) average method (10 studies), (2) summation method (8 studies), (3) magnitude method (7 studies), and (4) weighting method (2 studies). Conclusion: According to this review study, each of the indexes all has pros and cons, the research purpose and application field were different between each other, so a comparison would be needed to find the best index for quantifying the "total muscle activity" in the future. Application: The results of this review study might help to determine the method for quantifying the total muscle activity of muscle groups.

The aim of this study was to test the effect of face cooling with cold water (1.2 ± 0.7°C) vs. fa... more The aim of this study was to test the effect of face cooling with cold water (1.2 ± 0.7°C) vs. face cooling with neutral water (28.0 ± 3.0°C) during high-intensity swimming training on both the core temperature (Tco) and thermal perceptions in internationally ranked long-distance swimmers (5 men’s and 3 women’s) during 2 randomized swimming sessions. After a standardized warm-up of 1,200 m, the athletes performed a standardized training session that consisted of 2,000 m (5 × 400 m; start every 5’15”) at a best velocity then 600 m of aerobic work. Heart rate (HR) was continuously monitored during 5 × 400 m, whereas Tco, thermal comfort (TC), and thermal sensation (TS) were measured before and after each 400 m. Before and after each 400 m, the swimmers were asked to flow 200 mL of cold water (1.2°C) or neutral (22°C) water packaged in standardized bottles on their face. The swimmers were asked don’t drink during exercise. The velocity was significantly different between cold water and...

Afin de mieux comprendre les effets thermo-physiologiques de la plongee prolongee en eau froide, ... more Afin de mieux comprendre les effets thermo-physiologiques de la plongee prolongee en eau froide, une etude a ete conduite chez 10 plongeurs professionnels de la Marine nationale. Ils ont realise plusieurs immersions statiques completes pendant 6 heures a differents niveaux de temperature d’eau : 34°C sans protection thermique et deux en eau froide (18°C et 10°C) avec une combinaison de protection speciale. Des mesures thermiques, metaboliques et endocriniennes ont ete effectuees avant, pendant et au decours de ces immersions. A 34°C, un equilibre thermique quasi-parfait est maintenu pendant toute la duree de l’immersion et aucun ajustement metabolique significatif n’est observe. En eau froide et malgre la protection vestimentaire, la temperature corporelle profonde (Tco) diminue de facon reguliere et continue pendant toute l’immersion, de facon identique dans les deux situations (36,2 ± 0. 4 °C a la fin). La temperature cutanee moyenne (mTsk) diminue de facon rapide et importante au...

BACKGROUND Oxygen divers undergo environmental stressors such as immersion, ventilation with scub... more BACKGROUND Oxygen divers undergo environmental stressors such as immersion, ventilation with scuba, cold exposure, and increased ambient pressure. All of these stressors may be responsible for acute hemodynamic modifications. We hypothesized that repeated hyperbaric hyperoxia exposure induces long-term cardiovascular modifications. METHODS A Doppler echocardiography was conducted on 20 military oxygen divers (average 12 yr diving experience) and compared with 22 controls. Parameters known to be modified by acute hyperoxic exposure, such as left ventricular (LV) function (systolic and diastolic) and arterial compliance, were analyzed. RESULTS Controls and divers were matched appropriately for age and height, although the divers had a higher body mass index and aerobic capacity. Left atrial and left ventricular diameters did not differ between the two groups. On the other hand, left ventricular mass was significantly higher in the elite military divers (209 +/- 43 g) in comparison wit...

Life

The practice of physical activity in a variable climate during the same competition is becoming m... more The practice of physical activity in a variable climate during the same competition is becoming more and more common due to climate change and increasingly frequent climate disturbances. The main aim of this pilot study was to understand the impact of cold ambient temperature on performance factors during a professional cycling race. Six professional athletes (age = 27 ± 2.7 years; height = 180.86 ± 5.81 cm; weight = 74.09 ± 9.11 kg; % fat mass = 8.01 ± 2.47%; maximum aerobic power (MAP) = 473 ± 26.28 W, undertook ~20 h training each week at the time of the study) participated in the Tour de la Provence under cold environmental conditions (the ambient temperature was 15.6 ± 1.4 °C with a relative humidity of 41 ± 8.5% and the normalized ambient temperature (Tawc) was 7.77 ± 2.04 °C). Body core temperature (Tco) was measured with an ingestible capsule. Heart rate (HR), power, speed, cadence and the elevation gradient were read from the cyclists’ onboard performance monitors. The inte...

Revue Européenne de Psychologie Appliquée/European Review of Applied Psychology, 2015

Introduction.-Colors may influence motor performance. Objective.-The present study aimed to compa... more Introduction.-Colors may influence motor performance. Objective.-The present study aimed to compare the effects of perception of red and green environments on physical (performance and heart rate) and psychological (perceived effort, anxiety and enjoyment) parameters during cycling trials. Method.-Ten cyclists achieved two identical series of three randomized 7-minute trials on home trainers, during which they were continuously exposed to red, green, and gray environments. Covered distance and heart rate were recorded during each trial, after which participants answered items intended to assess perceived effort, anxiety, and enjoyment experienced during the trial. Results.-Results showed that covered distance (ps ≤ .02) and heart rate (ps ≤ .03) were lower in the red environment than in the gray and green environments. Enjoyment was higher in the green environment than in the red environment (p = .006). The colored environments did not influence perceived effort and anxiety (ps > .05). Conclusion.-This study is the first to show that perceiving red is detrimental for motor performance over an extended period of time.

Applied Physiology, Nutrition, and Metabolism

Endurance exercise performance is impaired in a hot and humid environment. This study compared th... more Endurance exercise performance is impaired in a hot and humid environment. This study compared the effects of cold water immersion, with (CMWI) and without (CWI) menthol, on the recovery of cycling performance. Eight heat-acclimatized cyclists (age, 24.1 ± 4.4 years; mass, 65.3 ± 5.2 kg) performed 2 randomized sessions, each consisting of a 20-min cycling trial (T1) followed by 10 min of immersion during recovery and then a second 20-min cycling trial (T2). Mean power output and perceived exertion (RPE) were recorded for both trials. Rectal (Trec) and skin temperatures were measured before and immediately after T1, immersion, and T2. Perceived thermal sensation (TS) and comfort were measured immediately after T1 and T2. Power output was significantly improved in T2 compared with T1 in the CMWI condition (+15.6%). Performance did not change in the CWI condition. After immersion, Trec was lower in CWI (–1.17 °C) than in CMWI (–0.6 °C). TS decreased significantly after immersion in bot...

Sports

This systematic review and meta-analysis aimed to assess studies which have investigated cooling ... more This systematic review and meta-analysis aimed to assess studies which have investigated cooling methodologies, their timing and effects, on endurance exercise performance in trained athletes (Category 3; VO 2max ≥ 55 mL•kg•min −1) in hot environmental conditions (≥28 • C). Meta-analyses were performed to quantify the effects of timings and methods of application, with a narrative review of the evidence also provided. A computer-assisted database search was performed for articles investigating the effects of cooling on endurance performance and accompanying physiological and perceptual responses. A total of 4129 results were screened by title, abstract, and full text, resulting in 10 articles being included for subsequent analyses. A total of 101 participants and 310 observations from 10 studies measuring the effects of differing cooling strategies on endurance exercise performance and accompanying physiological and perceptual responses were included. With respect to time trial performance, cooling was shown to result in small beneficial effects when applied before and throughout the exercise bout (Effect Size: −0.44; −0.69 to −0.18), especially when ingested (−0.39; −0.60 to −0.18). Current evidence suggests that whilst other strategies ameliorate physiological or perceptual responses throughout endurance exercise in hot conditions, ingesting cooling aids before and during exercise provides a small benefit, which is of practical significance to athletes' time trial performance.

Plos One, Mar 1, 2015

A recent laboratory study demonstrated that the ingestion of a cold/menthol beverage improved exe... more A recent laboratory study demonstrated that the ingestion of a cold/menthol beverage improved exercise performance in a hot and humid environment during 20 km of all-out cycling. Therefore, the aim of this study was to determine whether the ingestion of cold water/ ice-slurry with menthol would improve performance in hot and humid outdoor conditions.

International Journal of Sports Medicine, 2015

Medécine et armées

Introduction : l'analyse spectrale de la variabilité de l'intervalle RR permet une évalua... more Introduction : l'analyse spectrale de la variabilité de l'intervalle RR permet une évaluation de l'activité du système nerveux autonome (SNA). Le but de cette étude était de déterminer les effets d'un programme militaire de formation à la plongée sous marine sur l'activité du SNA. Méthodes : Une mesure de la pression artérielle ainsi qu'un enregistrement électro-cardiographique battement par battement ont été réalisés chez 12 témoins non sédentaires et 12 militaires, admis à un cours de plongeurs professionnels. Ces derniers ont été évalués avant et après une formation de 15 semaines à la plongée sous-marine. Résultats : Après la formation, il existe une diminution significative de la pression artérielle systolique et de la pression pulsée aussi bien au bras qu'à la cheville. La fréquence cardiaque (bpm) est plus élevée chez les témoins (63 ± 8 bpm versus 54 ± 8 bpm – PRE ; 53 ± 5 bpm – POST). En fin de stage, les plongeurs ont des valeurs de Basses Fréqu...