Mild preexercise hyperhydration with electrolyte-containing beverages: effect on thirst, water intake, and physiologic function

The American College of Sports Medicine\u27s (ACSM) position stand on appropriate fluid intake for long duration exercise states that individuals should drink fluids containing sodium (0.5 - 0.7 g/l), potassium (0.08 - 0.2 g/l), and carbohydrate (5 - 10%) at a rate of 400 - 800 ml/h, depending on the individual\u27s sweat rate and body size, in order to keep body water losses \u3c 2%. The ACSM guidelines for preexercise hydration are unclear. Beverages containing significant amounts of sodium increase water intake and retention, subsequently improving fluid balance during and after exercise. However, whether sodium containing beverages ingested before exercise influence water intake and urine production during endurance exercise has not been studied. Two primary studies were conducted in order to test the efficacy of chicken noodle soup (167 mmol Na+/l) to improve fluid balance by increasing water intake and retention during exercise in thermoneutral (WBGT = 16°C) and hot, dry (WBGT = 26°C) environments. In both studies, fluid balance was improved during 90 min of moderate intensity exercise (∼55% VO2peak) 45 min after ingesting 355 ml of chicken noodle soup (CNS) compared with a similar quantity of water (WATER). The improvement in fluid balance was mainly because of an increase in ad libitum water intake that persisted throughout the 90 min of exercise. The increase in water intake was apparent in both the thermoneutral (801 +/- 415 vs. 594 +/- 391; CNS vs. WATER) and hot, dry (1434 +/- 592 vs. 1163 +/- 427; CNS vs. WATER) environments. Water retention was also improved after CNS in the thermoneutral environment, but not the hot, dry environment despite decreased calculated free water clearance in both studies. Although fluid balance was greater in both studies, no cardiovascular, temperature regulatory, or performance benefits were observed. Perceived thirst was also similar in all trials when water intake was allowed ad libitum. When water ingested at a similar rate to the CNS trial during a second water hyperhydration trial (WATER/R) in the hot, dry environment, ratings of perceived thirst decreased. Interestingly, when participants were forced to drink more water than normal in the hot, dry environment (WATER/R) without the additional preexercise sodium load (CNS), plasma sodium concentrations were consistently lower during exercise. From these studies we conclude that preexercise beverage composition can affect both dipsogenic drive and kidney function resulting in improved body water status during exercise. Also, these results indicate that it may not be necessary to replace sodium losses during exercise if anticipated losses are ingested before exercise

Boost your brain: a simple 100% normobaric oxygen treatment improves human motor learning processes

IntroductionHuman motor learning processes are a fundamental part of our daily lives and can be adversely affected by neurologic conditions. Motor learning largely depends on successfully integrating cognitive and motor-related sensory information, and a simple, easily accessible treatment that could enhance such processes would be exciting and clinically impactful. Normobaric 100% oxygen treatment (NbOxTr) is often used as a first-line intervention to improve survival rates of brain cells in neurological trauma, and recent work indicates that improvements in elements crucial for cognitive-motor-related functions can occur during NbOxTr. However, whether NbOxTr can enhance the motor learning processes of healthy human brains is unknown. Here, we investigated whether a brief NbOxTr administered via nasal cannula improves motor learning processes during a visuomotor adaptation task where participants adapt to a visual distortion between visual feedback and hand movements.Methods40 healthy young adults (M = 21 years) were randomly assigned to a NbOxTr (N = 20; 100% oxygen) or air (N = 20; regular air) group and went through four typical visuomotor adaptation phases (Baseline, Adaptation, After-Effect, Refresher). Gas treatment (flow rate 5 L/min) was only administered during the Adaptation phase of the visuomotor experiment, in both groups.ResultsThe NbOxTr provided during the Adaptation phase led to significantly faster and about 30% improved learning (p < 0.05). Notably, these motor learning improvements consolidated into the subsequent experiment phases, i.e., after the gas treatment was terminated (p < 0.05).DiscussionWe conclude that this simple and brief NbOxTr dramatically improved fundamental human motor learning processes and may provide promising potential for neurorehabilitation and skill-learning approaches. Further studies should investigate whether similar improvements exist in elderly and neurologically impaired individuals, other motor learning tasks, and also long-lasting effects

Emerging professional skills: Insights and methods

In this workshop run by the Engineering skills SIG, attendees were given the opportunity to learn about emerging professional competencies, and strategies to overcome teaching barriers.The workshop format was “world cafe” with several tables for small groups to informally discuss these strategies within a time limit. Each table focussed on an emerging skill and/or scenario and participants each visited several tables. The session was informed by the engineering skills survey taken by SEFI 2021 conference attendees. It gave us views on new competencies, barriers to teaching them, and illustrations of good practice. Obstacles to teaching them include motivation, legitimacy, overloaded curriculums, student resistance, resource constraints, and pedagogical understandings.Ideally skills should be learned by students in contexts where they’re used. While many technical competencies are primarily developed in engineering practice, professional/soft abilities are often not. As a result, there ought to be some opportunity for the student to transfer, adapt and (re)learn them in an engineering degree. This report summarises the conference workshop outputs with sections for each table. Each section acknowledges the hosts/authors, a summary of the discussion, and any materials presented. Readers may find this paper useful when facilitating related discussions

Who, What, How? Tackling Skills Challenges: Future Relevance, Stakeholder Differences, And Teaching Hurdles

The Engineering Skills Special Interest Group (SIG) ran a workshop on the current challenges in teaching engineering skills. This workshop employed the “world café” participatory method where attendees visited three tables for a structured discussion with a member of the SIG. Each table posed a different question: On the What? table we discussed which skills are most relevant for future practitioners. The Who? table focussed on the differences in the way that various professional skills are conceptualised by main stakeholders. Finally, at the How? table we discussed the facilitators and barriers in designing and delivering skills education. The outcome of the workshop presented here is a mapping of skills in terms of present and future importance to attendees and their countries, and a classification of stakeholders in terms of macro, meso, micro level when considering their influence over skill conceptualisation and realisation

PGC1α

PGC1α, a transcriptional coactivator, interacts with PPARs and others to regulate skeletal muscle metabolism. PGC1α undergoes splicing to produce several mRNA variants, with the NTPGC1α variant having a similar biological function to the full length PGC1α (FLPGC1α). CVD is associated with obesity and T2D and a lower percentage of type 1 oxidative fibers and impaired mitochondrial function in skeletal muscle, characteristics determined by PGC1α expression. PGC1α expression is epigenetically regulated in skeletal muscle to determine mitochondrial adaptations, and epigenetic modifications may regulate mRNA splicing. We report in this paper that skeletal muscle PGC1α  −1 nucleosome (−1N) position is associated with splice variant NTPGC1α but not FLPGC1α expression. Division of participants based on the −1N position revealed that those individuals with a −1N phased further upstream from the transcriptional start site (UP) expressed lower levels of NTPGC1α than those with the −1N more proximal to TSS (DN). UP showed an increase in body fat percentage and serum total and LDL cholesterol. These findings suggest that the −1N may be a potential epigenetic regulator of NTPGC1α splice variant expression, and −1N position and NTPGC1α variant expression in skeletal muscle are linked to CVD risk. This trial is registered with clinicaltrials.gov, identifier NCT00458133

Determinants of the changes in glycemic control with exercise training in type 2 diabetes:A randomized trial

To assess the determinants of exercise training-induced improvements in glucose control (HbA1C) including changes in serum total adiponectin and FFA concentrations, and skeletal muscle peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) protein content.A sub-cohort (n = 35; 48% men; 74% Caucasian) from the HART-D study undertaking muscle biopsies before and after 9 months of aerobic (AT), resistance (RT), or combination training (ATRT).Changes in HbA1C were associated with changes in adiponectin (r = -0.45, P = 0.007). Participants diagnosed with type 2 diabetes for a longer duration had the largest increase in PGC-1α (r = 0.44, P = 0.008). Statistical modeling examining changes in HbA1C suggested that male sex (P = 0.05), non-Caucasian ethnicity (P = 0.02), duration of type 2 diabetes (r = 0.40; P<0.002) and changes in FFA (r = 0.36; P<0.004), adiponectin (r = -0.26; P<0.03), and PGC-1α (r = -0.28; P = 0.02) explain ∼65% of the variability in the changes in HbA1C.Decreases in HbA1C after 9 months of exercise were associated with shorter duration of diabetes, lowering of serum FFA concentrations, increasing serum adiponectin concentrations and increasing skeletal muscle PGC-1α protein expression.ClinicalTrials.gov NCT00458133

Exercise-induced changes in central adiposity during a RCT: effect of exercise dose and associations with compensation

Context: Exercise can decrease central adiposity, but the effect of exercise dose and the relationship between central adiposity and exercise-induced compensation is unclear. Objective: Test the effect of exercise dose on central adiposity change and the association between central adiposity and exercise-induced weight compensation. Methods: In this ancillary analysis of a 6-month randomized controlled trial, 170 participants with overweight or obesity (mean±SD BMI: 31.5±4.7 kg/m2) were randomized to a control group or exercise groups that reflected exercise recommendations for health (8 kcal/kg/week [KKW]) or weight loss and weight maintenance (20 KKW). Waist circumference was measured, and dual-energy X-ray absorptiometry assessed central adiposity. Predicted weight change was estimated and weight compensation (weight change minus predicted weight change) was calculated. Results: Between-group change in waist circumference (control: 0.0 cm [95% CI: -1.0,1.0], 8 KKW: -0.7 cm [95% CI: -1.7,0.4], 20 KKW: -1.3 cm [95% CI: -2.4, -0.2]) and visceral adipose tissue (VAT; control: -0.02 kg [95% CI: -0.07,0.04], 8 KKW: -0.01 kg [95% CI: -0.07,0.04], 20 KKW: -0.04 kg [95% CI: -0.10,0.02]) was similar (P≥0.23). Most exercisers (82.6%) compensated (predicted weight change lower than actual weight change). Exercisers who compensated exhibited a 2.5 cm (95% CI: 0.8,4.2) and 0.23 kg (95% CI: 0.14,0.31) increase in waist circumference and VAT, respectively, versus those who did not (P&lt;0.01). Desire to eat predicted VAT change during exercise (β=0.21; P=0.03). Conclusions: In the presence of significant weight compensation, exercise at doses recommended for health and weight loss and weight maintenance leads to negligible changes in central adiposity

Precision exercise medicine: understanding exercise response variability

There is evidence from human twin and family studies as well as mouse and rat selection experiments that there are considerable interindividual differences in the response of cardiorespiratory fitness (CRF) and other cardiometabolic traits to a given exercise programme dose. We developed this consensus statement on exercise response variability following a symposium dedicated to this topic. There is strong evidence from both animal and human studies that exercise training doses lead to variable responses. A genetic component contributes to exercise training response variability. In this consensus statement, we (1) briefly review the literature on exercise response variability and the various sources of variations in CRF response to an exercise programme, (2) introduce the key research designs and corresponding statistical models with an emphasis on randomised controlled designs with or without multiple pretests and post-tests, crossover designs and repeated measures designs, (3) discuss advantages and disadvantages of multiple methods of categorising exercise response levels-a topic that is of particular interest for personalised exercise medicine and (4) outline approaches that may identify determinants and modifiers of CRF exercise response. We also summarise gaps in knowledge and recommend future research to better understand exercise response variability531811411153The consensus meeting that led to the writing of this manuscript was held with the financial support of the Pennington Biomedical Research Foundation, the Pennington Biomedical Research Center Division of Education, the LSU Boyd Professorship and the John W. Barton, Sr. Chair in Genetics and Nutrition. No funding and/or honorarium was provided to any member of the writing group for the production of this manuscrip

The Effect of Exercise Training Modality on Serum Brain Derived Neurotrophic Factor Levels in Individuals with Type 2 Diabetes

Introduction: Brain derived neurotrophic factor (BDNF) has been implicated in memory, learning, and neurodegenerative disease. However, the relationship of BDNF with cardiometabolic risk factors is unclear, and the effect of exercise training on BDNF has not been previously explored in individuals with type 2 diabetes. Methods: Men and women (N=150) with type 2 diabetes were randomized to an aerobic exercise (aerobic), resistance exercise (resistance), or a combination of both (combination) for 9 months. Serum BDNF levels were evaluated at baseline and follow-up from archived blood samples. Results: Baseline serum BDNF was not associated with fitness, body composition, anthropometry, glucose control, or strength measures (all, p\u3e0.05). Similarly, no significant change in serum BDNF levels was observed following exercise training in the aerobic (-1649.4 pg/ml, CI: -4768.9 to 1470.2), resistance (-2351.2 pg/ml, CI: -5290.7 to 588.3), or combination groups (-827.4 pg/ml, CI: -3533.3 to 1878.5) compared to the control group (-2320.0 pg/ml, CI: -5750.8 to 1110.8). However, reductions in waist circumference were directly associated with changes in serum BDNF following training (r=0.25, p=0.005). Conclusions: Serum BDF was not associated with fitness, body composition, anthropometry, glucose control, or strength measures at baseline. Likewise, serum BDNF measures were not altered by 9 months of aerobic, resistance, or combination training. However, reductions in waist circumference were associated with decreased serum BDNF levels. Future studies should investigate the relevance of BDNF with measures of cognitive function specifically in individuals with type-2 diabetes

Neonatal head and torso vibration exposure during inter-hospital transfer

Inter-hospital transport of premature infants is increasingly common, given the centralisation of neonatal intensive care. However, it is known to be associated with anomalously increased morbidity, most notably brain injury, and with increased mortality from multifactorial causes. Surprisingly, there have been relatively few previous studies investigating the levels of mechanical shock and vibration hazard present during this vehicular transport pathway. Using a custom inertial datalogger, and analysis software, we quantify vibration and linear head acceleration. Mounting multiple inertial sensing units on the forehead and torso of neonatal patients and a preterm manikin, and on the chassis of transport incubators over the duration of inter-site transfers, we find that the resonant frequency of the mattress and harness system currently used to secure neonates inside incubators is ~9Hz. This couples to vehicle chassis vibration, increasing vibration exposure to the neonate. The vibration exposure per journey (A(8) using the ISO 2631 standard) was at least 20% of the action point value of current European Union regulations over all 12 neonatal transports studied, reaching 70% in two cases. Direct injury risk from linear head acceleration (HIC15) was negligible. Although the overall hazard was similar, vibration isolation differed substantially between sponge and air mattresses, with a manikin. Using a Global Positioning System datalogger alongside inertial sensors, vibration increased with vehicle speed only above 60 km/h. These preliminary findings suggest there is scope to engineer better systems for transferring sick infants, thus potentially improving their outcomes