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Inducing a heat-acclimated phenotype via repeated heat stress improves exercise capacity and reduces athletes̓ risk of hyperthermia and heat illness. Given the increased number of international sporting events hosted in countries with warmer climates, heat acclimation strategies are increasingly popular among endurance athletes to optimize performance in hot environments. At the tissue level, completing endurance exercise under heat stress may augment endurance training adaptation, including mitochondrial and cardiovascular remodeling due to increased perturbations to cellular homeostasis as a consequence of metabolic and cardiovascular load, and this may improve endurance training adaptation and subsequent performance. This review provides an up-to-date overview of the metabolic impact of heat stress during endurance exercise, including proposed underlying mechanisms of altered substrate utilization. Against this metabolic backdrop, the current literature highlighting the role of heat stress in augmenting training adaptation and subsequent endurance performance will be presented with practical implications and opportunities for future research. [ABSTRACT FROM AUTHOR]

Over the past three decades, how plants sense and respond to mechanical stress has become a flourishing field of research. The pivotal role of mechanosensing in organogenesis and acclimation was demonstrated in various plants, and links are emerging between gene regulatory networks and physical forces exerted on tissues. However, how plant cells convert physical signals into chemical signals remains unclear. Numerous studies have focused on the role played by mechanosensitive (MS) calcium ion channels MCA, Piezo and OSCA. To complement these data, we combined data mining and visualization approaches to compare the tissue-specific expression of these genes, taking advantage of recent single-cell RNA-sequencing data obtained in the root apex and the stem of Arabidopsis and the Populus stem. These analyses raise questions about the relationships between the localization of MS channels and the localization of stress and responses. Such tissue-specific expression studies could help to elucidate the functions of MS channels. Finally, we stress the need for a better understanding of such mechanisms in trees, which are facing mechanical challenges of much higher magnitudes and over much longer time scales than herbaceous plants, and we mention practical applications of plant responsiveness to mechanical stress in agriculture and forestry.

This Article brings new perspectives on the well-known Viking and Laval cases, decided by the Court of Justice of the European Union (CJEU) in December 2007, by studying the processes and modalities of the construction of this case law as a major defeat for social Europe. It demonstrates that the political and legal implications of these two rulings were socially constructed by a variety of European actors (especially trade unionists and academics specialising in labour law) rather than legally inscribed in the rulings. In doing so, the author defends a constructivist approach in the analysis of European case law, both contextual and processual. The Article is divided into two parts. The first retraces the pre-ruling construction of the Viking and Laval cases, and shows that trade union and academic actors as well as parliamentarians worked to construct the judgements on these cases as decisive landmarks for social Europe. The second part considers the process of interpretation of the rulings after they were delivered by the CJEU. It evidences the central role played by trade union and academic actors in promoting a critical reading of the rulings, arguing that the Court subordinated social rights to economic liberties. The Article concludes by showing that this interpretation has tended to become subject to consensus, to the extent that it is now European common sense. [ABSTRACT FROM AUTHOR]

Purpose: (1) To compare the sleep of female players from a professional soccer team to nonathlete controls across an in-season week and (2) to compare the sleep of core and fringe players from the same team on the night after a match to training nights. Methods: Using an observational design, 18 professional female soccer players and 18 female nonathlete controls were monitored for their sleep via wristwatch actigraphy across 1 week. Independent-sample t tests and Mann–Whitney U tests were performed to compare sleep between groups, while an analysis of variance compared sleep on training nights to the night after a match. Results: Soccer players had significantly greater sleep duration than nonathlete controls (+38 min; P =.009; d: 0.92), which may have resulted from an earlier bedtime (−00:31 h:min; P =.047; d: 0.70). The soccer players also had less intraindividual variation in bedtime than nonathletes (−00:08 h:min; P =.023; r:.38). Despite this, sleep-onset latency was significantly longer among soccer players (+8 min; P =.032; d: 0.78). On the night after a match, sleep duration of core players was significantly lower than on training nights (−49 min; P =.010; d: 0.77). In fringe players, there was no significant difference between nights for any sleep characteristic. Conclusions: During the in-season period, sleep duration of professional female soccer players is greater than nonathlete controls. However, the night after a match challenges the sleep of players with more match involvement and warrants priority of sleep hygiene strategies. [ABSTRACT FROM AUTHOR]

The major intrinsic protein (MIP) superfamily is a key part of the fungal transmembrane transport network. It facilitates the transport of water and low molecular weight solutes across biomembranes. The fungal uncharacterized X-Intrinsic Protein (XIP) subfamily includes the full protein diversity of MIP. Their biological functions still remain fully hypothetical. The aim of this study is still to deepen the diversity and the structure of the XIP subfamily in light of the MIP counterparts—the aquaporins (AQPs) and aquaglyceroporins (AQGPs)—and to describe for the first time their function in the development, biomass accumulation, and mycoparasitic aptitudes of the fungal bioagent Trichoderma atroviride. The fungus-XIP clade, with one member (TriatXIP), is one of the three clades of MIPs that make up the diversity of T. atroviride MIPs, along with the AQPs (three members) and the AQGPs (three members). TriatXIP resembles those of strict aquaporins, predicting water diffusion and possibly other small polar solutes due to particularly wider ar/R constriction with a Lysine substitution at the LE2 position. The XIP loss of function in ∆TriatXIP mutants slightly delays biomass accumulation but does not impact mycoparasitic activities. ∆TriatMIP forms colonies similar to wild type; however, the hyphae are slightly thinner and colonies produce rare chlamydospores in PDA and specific media, most of which are relatively small and exhibit abnormal morphologies. To better understand the molecular causes of these deviant phenotypes, a wide-metabolic survey of the ∆TriatXIPs demonstrates that the delayed growth kinetic, correlated to a decrease in respiration rate, is caused by perturbations in the pentose phosphate pathway. Furthermore, the null expression of the XIP gene strongly impacts the expression of four expressed MIP-encoding genes of T. atroviride, a plausible compensating effect which safeguards the physiological integrity and life cycle of the fungus. This paper offers an overview of the fungal XIP family in the biocontrol agent T. atroviride which will be useful for further functional analysis of this particular MIP subfamily in vegetative growth and the environmental stress response in fungi. Ultimately, these findings have implications for the ecophysiology of Trichoderma spp. in natural, agronomic, and industrial systems.

Purpose: Carbohydrate (CHO) intake periodization via the sleep low train low (SL‐TL) diet–exercise model increases fat oxidation during exercise and may enhance endurance‐training adaptation and performance. Conversely, training under environmental heat stress increases CHO oxidation, but the potential of combined SL‐TL and heat stress to enhance metabolic and performance outcomes is unknown. Methods: Twenty‐three endurance‐trained males were randomly assigned to either control (n = 7, CON), SL‐TL (n = 8, SLTemp) or SL‐TL + heat stress (n = 8, SLHeat) groups and prescribed identical 2‐week cycling training interventions. CON and SLTemp completed all sessions at 20°C, but SLHeat at 35°C. All groups consumed matched CHO intake (6 g·kg−1·day−1) but timed differently to promote low CHO availability overnight and during morning exercise in both SL groups. Submaximal substrate utilization was assessed (at 20°C), and 30‐min performance tests (at 20 and 35°C) were performed Pre‐, Post‐, and 1‐week post‐intervention (Post+1). Results: SLTemp improved fat oxidation rates at 60% MAP (~66% VO2peak) at Post+1 compared with CON (p < 0.01). Compared with SLTemp, fat oxidation rates were significantly lower in SLHeat at Post (p = 0.02) and Post+1 (p < 0.05). Compared with CON, performance was improved at Post in SLTemp in temperate conditions. Performance was not different between any groups or time points in hot conditions. Conclusion: SL‐TL enhanced metabolic adaptation and performance compared with CON and combined SL‐TL and heat stress. Additional environmental heat stress may impair positive adaptations associated with SL‐TL. [ABSTRACT FROM AUTHOR]

Major intrinsic proteins (MIP) are characterized by a transmembrane pore-type architecture that facilitates transport across biomembranes of water and a variety of low molecular weight solutes. They are found in all parts of life, with remarkable protein diversity. Very little is known about MIP from fungi. And yet, it can legitimately be stated that MIP are pivotal molecular components in the privileged relationships fungi enjoy with plants or soil fauna in various environments. To date, MIP have never been studied in a mycoparasitism situation. In this study, the diversity, expression and functional prediction of MIP from the genus Trichoderma were investigated. Trichoderma spp. genomes have at least seven aquaporin genes. Based on a phylogenetic analysis of the translated sequences, members were assigned to the AQP, AQGP and XIP subfamilies. In in vitro and in planta assays with T. harzianum strain Ths97, expression analyses showed that four genes were constitutively expressed. In a mycoparasitic context with Fusarium solani, the causative agent of fusarium dieback on olive tree roots, these genes were up-regulated. This response is of particular interest in analyzing the MIP promoter cis-regulatory motifs, most of which are involved in various carbon and nitrogen metabolisms. Structural analyses provide new insights into the possible role of structural checkpoints by which these members transport water, H2O2, glycerol and, more generally, linear polyols across the membranes. Taken together, these results provide the first evidence that MIP may play a key role in Trichoderma mycoparasitism lifestyle.

Master athletes are often considered exemplars of successful aging, thanks to their capacity to maintain a high sports performance during their entire life. A high training capacity, regular participation in sporting competitions, and delayed alterations in body composition and physiological capacities have been listed among the main factors contributing to impressive master athletes' performances.However, there is a paucity of data on themetabolismand dietary habits ofmaster athletes, and the question ofwhether they need to adapt their nutrition to the aging process remains open. Herein, the authors presented a contemporary overview of the metabolic challenges associatedwith aging, including the risk of low energy availability, anabolic resistance, and periods ofmetabolic crisis due to forced immobilization. After assembling scientific evidence to show that master athletes must adapt their dietary intake, the authors proposed a summary of nutritional recommendations for master athletes and suggested the next stage of research. [ABSTRACT FROM AUTHOR]