Hydration and cooling in elite athletes: relationship with performance, body mass loss and body temperatures during the Doha 2019 IAAF World Athletics Championships

Purpose: To characterise hydration, cooling, body mass loss, and core (Tcore) and skin (Tsk) temperatures during World Athletics Championships in hot-humid conditions. Methods: Marathon and race-walk (20 km and 50 km) athletes (n=83, 36 women) completed a pre-race questionnaire. Pre-race and post-race body weight (n=74), Tcore (n=56) and Tsk (n=49; thermography) were measured. Results: Most athletes (93%) had a pre-planned drinking strategy (electrolytes (83%), carbohydrates (81%)) while ice slurry was less common (11%; p<0.001). More men than women relied on electrolytes and carbohydrates (91%–93% vs 67%–72%, p≤0.029). Drinking strategies were based on personal experience (91%) rather than external sources (p<0.001). Most athletes (80%) planned pre-cooling (ice vests (53%), cold towels (45%), neck collars (21%) and ice slurry (21%)) and/or midcooling (93%; head/face dousing (65%) and cold water ingestion (52%)). Menthol usage was negligible (1%–2%). Pre-race Tcore was lower in athletes using ice vests (37.5°C±0.4°C vs 37.8°C±0.3°C, p=0.024). Tcore (pre-race 37.7°C±0.3°C, post-race 39.6°C±0.6°C) was independent of event, ranking or performance (p≥0.225). Pre-race Tsk was correlated with faster race completion (r=0.32, p=0.046) and was higher in non-finishers (did not finish (DNF); 33.8°C±0.9°C vs 32.6°C±1.4°C, p=0.017). Body mass loss was higher in men than women (−2.8±1.5% vs −1.3±1.6%, p<0.001), although not associated with performance. Conclusion: Most athletes’ hydration strategies were pre-planned based on personal experience. Ice vests were the most adopted pre-cooling strategy and the only one minimising Tcore, suggesting that event organisers should be cognisant of logistics (ie, freezers). Dehydration was moderate and unrelated to performance. Pre-race Tsk was related to performance and DNF, suggesting that Tsk modulation should be incorporated into pre-race strategies

Hydration and cooling in elite athletes: relationship with performance, body mass loss and body temperatures during the Doha 2019 IAAF World Athletics Championships.

PURPOSE: To characterise hydration, cooling, body mass loss, and core (Tcore) and skin (Tsk) temperatures during World Athletics Championships in hot-humid conditions. METHODS: Marathon and race-walk (20 km and 50 km) athletes (n=83, 36 women) completed a pre-race questionnaire. Pre-race and post-race body weight (n=74), Tcore (n=56) and Tsk (n=49; thermography) were measured. RESULTS: Most athletes (93%) had a pre-planned drinking strategy (electrolytes (83%), carbohydrates (81%)) while ice slurry was less common (11%; p<0.001). More men than women relied on electrolytes and carbohydrates (91%-93% vs 67%-72%, p≤0.029). Drinking strategies were based on personal experience (91%) rather than external sources (p<0.001). Most athletes (80%) planned pre-cooling (ice vests (53%), cold towels (45%), neck collars (21%) and ice slurry (21%)) and/or mid-cooling (93%; head/face dousing (65%) and cold water ingestion (52%)). Menthol usage was negligible (1%-2%). Pre-race Tcore was lower in athletes using ice vests (37.5°C±0.4°C vs 37.8°C±0.3°C, p=0.024). Tcore (pre-race 37.7°C±0.3°C, post-race 39.6°C±0.6°C) was independent of event, ranking or performance (p≥0.225). Pre-race Tsk was correlated with faster race completion (r=0.32, p=0.046) and was higher in non-finishers (did not finish (DNF); 33.8°C±0.9°C vs 32.6°C±1.4°C, p=0.017). Body mass loss was higher in men than women (-2.8±1.5% vs -1.3±1.6%, p<0.001), although not associated with performance. CONCLUSION: Most athletes' hydration strategies were pre-planned based on personal experience. Ice vests were the most adopted pre-cooling strategy and the only one minimising Tcore, suggesting that event organisers should be cognisant of logistics (ie, freezers). Dehydration was moderate and unrelated to performance. Pre-race Tsk was related to performance and DNF, suggesting that Tsk modulation should be incorporated into pre-race strategies

Hardware Implementation of FTC of Induction Machine on FPGA

In this paper, a new design method of Direct Torque Control using Space Vector Modulation (DTC-SVM) of an Induction Machine (IM), which is based on Fault Tolerant Control (FTC) is proposed. Due to its complexity, the FTC implemented on a microcontroller and a Digital Signal Processor (DSP) is characterized by a calculating delay. To solve this problem, an alternative digital solution is used, based on the Field Programmable Gate Array (FPGA), which is characterized by a fast processing speed. However, as an FPGAs increase in size, there is a need for improved productivity, and this includes new design flows and tools. Xilinx System Generator (XSG) is a high-level block-based design tool that offers bit and cycle accurate simulation. This tool can automatically generate the Very High-Density Logic (VHDL) code without resorting to a tough programming, without being obliged to do approximations and more we can visualize the behavior of the machine before implementation which is very important for not damage our machine. Simulation and experimental results using Hardware In the Loop (HIL) of the FTC based DTC-SVM is compared with those of the conventional DTC. The comparison results illustrate the reduction in the torque and stator flux ripples. Our purpose is to reveal our algorithm efficiency and to show the Xilinx Virtex V FPGA performances in terms of execution time.

Hardware software co-simulation of a digital EMI filter using Xilinx system generator

Mitigation of electromagnetic inference (EMI) is currently a challenge for scientists and designers in order to cope with electromagnetic compatibility (EMC) compliance in switching mode power supply (SMPS) and ensure the reliability of the whole system. Standard filtering techniques: passive and active ones present some insufficiency in terms of performance at high frequencies (HF) because analog components would no longer be controllable and this is mainly due to their parasitic elements. So developing EMI digital filters is very interesting, especially with the embedment of a machine control system on a field programmable gate array (FPGA) chip. In this paper, we present a design of an active digital EMI filter (ADF) to be integrated in a drive train system of an electric vehicle (EV). Hardware design as well as FPGA implementation issues have been presented to prove the efficiency of the developed digital filtering structure

Integrated Maintenance-Quality strategies taking into account the impact of the system degradation on the quality of output products.

This paper deals with integrated models joining maintenance and quality. We consider a manufacturing system composed of a single machine subject to an increased random failure rate and producing conforming and non-conforming items. In order to decrease the random failure rate and its impact on the quality of output products, a bloc type preventive maintenance strategy with minimal repair is considered. Our study consists in developing integrated analytical models joining maintenance and quality in order to determine the optimal preventive maintenance plan taking into account the progressive quality perturbation and the economic impact of reworking activities. Two strategies are developed. In fact, for the first strategy, we propose reworking activities for all non-conforming products in order to improve their quality condition and to sell all batches at the best price Pmax. The aim of this strategy is to found the optimal number of batches produced and reworked N* before each preventive maintenance action, maximizing the total net profit per time unit PT1. For the second strategy, the same problem is studied but for a finite horizon. Two mathematical models are developed in order to find the optimal value of the decision variable N* for both strategies. Numerical examples are presented in order to illustrate proposed models and a sensitivity study is developed to evaluate the influence of the variation of some parameters.

Heat stress impairs proprioception but not running mechanics

Objectives To determine the effects of heat stress on ankle proprioception and running gait pattern. Design Counterbalanced repeated measures. Methods 12 trained runners performed a proprioception test (active movement discrimination) before and immediately after a 30 min, self-paced treadmill run in HOT (39 °C) and COOL (22 °C) ambient conditions. Velocity was imposed during the first and last minute (70% of maximal aerobic velocity, 13.3 ± 0.8 km h−1) for determination of running mechanics and spring–mass characteristics. Results Rectal (39.7 ± 0.4 vs. 39.4 ± 0.4 °C), skin (36.3 ± 1.1 vs. 31.8 ± 1.1 °C) and average body (38.3 ± 0.2 vs. 36.4 ± 0.4 °C) temperatures together with heart rate (178 ± 8 vs. 174 ± 6 bpm) and thermal discomfort (6.5 ± 0.5 vs. 4.3 ± 1.3) were all higher at the end of the HOT compared to COOL run (all p  0.05). Conclusions Heat stress exacerbates thermal, cardiovascular and perceptual responses, while running velocity was slower during a 30 min self-paced treadmill run. Heat stress also impairs ankle proprioception during an active movement discrimination task, but it has no influence on gait pattern assessed at a constant, sub-maximal velocity.The authors thank Clint Hansen for his methodological input. The authors thank Mohammed Aziz Farooq for his support with the statistical analysis. The authors thank the participants for their involvement. The results of this study are presented clearly, honestly, and without fabrication, falsification, or inappropriate data manipulation. This study was internally funded by Aspetar Orthopedic and Sports Medicine Hospital . This project was conducted using an instrumented treadmill that was funded by QNRF (NPRP 4-760-3-217).Scopu

Cost-Effectiveness of once-daily, single-inhaler indacaterol acetate/ glycopyrronium bromide/ mometasone furoate in Patients with uncontrolled moderate-to-severe asthma in Canada

This is the final version. Available from Dove Medical Press via the DOI in this record. Data are available from the corresponding author upon reasonable request.Purpose: We evaluated the cost-effectiveness of high-dose indacaterol acetate (IND)/glycopyrronium bromide (GLY)/mometasone furoate (MF) (150/50/160 μg, once daily) compared with high-dose salmeterol/fluticasone (SAL/FLU; 50/500 µg, twice daily)+tiotropium (TIO; 5 µg, once daily) (SAL/FLU+TIO) and with high-dose SAL/FLU (50/500 µg, twice daily) for the treatment of inadequately controlled moderate-to-severe asthma. Patients and Methods: A Markov model estimated the incremental cost-effectiveness ratio of treatment with high-dose IND/GLY/MF compared with SAL/FLU+TIO and high-dose IND/GLY/MF compared with SAL/FLU. The model included three health states (day-to-day symptoms without exacerbations, day-to-day symptoms with exacerbations, and death) with a 4-week cycle length. A lifetime time horizon was used. Exacerbation rates and utility values were derived from ARGON and IRIDIUM clinical trials. Canadian dollars (CAD$, 2020) were applied. Results: IND/GLY/MF was the less costly and more effective treatment strategy compared with SAL/FLU+TIO and SAL/FLU in the base-case analyses. IND/GLY/MF had lower costs (CAD$33,501 versus CAD $50,907) and higher quality-adjusted life-years (QALYs) (18.37 versus 18.06 QALYs) compared with SAL/FLU+TIO. Compared with SAL/FLU, IND/GLY/ MF had lower costs (CAD$33,408 versus CAD $36,577) and higher QALYs (19.33 versus 19.04 QALYs). IND/GLY/MF was the most cost-effective option in all scenarios tested. Conclusion: IND/GLY/MF was cost-effective at a willingness-to-pay threshold of CAD$50,000/QALY in patients with uncontrolled, moderate-to-severe asthma versus SAL/FLU +TIO and SAL/FLU in the base case and all scenarios tested. Keywords: moderate to severe asthma, indacaterol acetate, glycopyrronium bromide, mometasone furoate, cost-effectiveness, health care payer perspective, Canada, uncontrolled asthmaNovartis Pharma A