Sexually dimorphic effects of prenatal alcohol exposure on the murine skeleton

Background: Prenatal alcohol exposure (PAE) can result in lifelong disabilities known as foetal alcohol spectrum disorder (FASD) and is associated with childhood growth deficiencies and increased bone fracture risk. However, the effects of PAE on the adult skeleton remain unclear and any potential sexual dimorphism is undetermined. Therefore, we utilised a murine model to examine sex differences with PAE on in vitro bone formation, and in the juvenile and adult skeleton. Methods: Pregnant C57BL/6J female mice received 5% ethanol in their drinking water during gestation. Primary calvarial osteoblasts were isolated from neonatal offspring and mineralised bone nodule formation and gene expression assessed. Skeletal phenotyping of 4- and 12-week-old male and female offspring was conducted by micro-computed tomography (µCT), 3-point bending, growth plate analyses, and histology.Results: Osteoblasts from male and female PAE mice displayed reduced bone formation, compared to control (≤30%). Vegfa, Vegfb, Bmp6, Tgfbr1, Flt1 and Ahsg were downregulated in PAE male osteoblasts only, whilst Ahsg was upregulated in PAE females. In 12-week-old mice, µCT analysis revealed a sex and exposure interaction across several trabecular bone parameters. PAE was detrimental to the trabecular compartment in male mice compared to control, yet PAE females were unaffected. Both male and female mice had significant reductions in cortical parameters with PAE. Whilst male mice were negatively affected along the tibial length, females were only distally affected. Posterior cortical porosity was increased in PAE females only. Mechanical testing revealed PAE males had significantly reduced bone stiffness compared to controls; maximum load and yield were reduced in both sexes. PAE had no effect on total body weight or tibial bone length in either sex. However, total growth plate width in male PAE mice compared to control was reduced, whilst female PAE mice were unaffected. 4-week-old mice did not display the altered skeletal phenotype with PAE observed in 12-week-old animals. Conclusions: Evidence herein suggests, for the first time, that PAE exerts divergent sex effects on the skeleton, possibly influenced by underlying sex-specific transcriptional mechanisms of osteoblasts. Establishing these sex differences will support future policies and clinical management of FASD.<br/

Ethical dilemmas and validity issues related to the use of new cooling technologies and early recognition of exertional heat illness in sport

The Tokyo 2020 Olympic Games is expected to be among the hottest Games in modern history, increasing the chances for exertional heat stroke (EHS) incidence, especially in non-acclimatised athletes/workers/spectators. The urgent need to recognise EHS symptoms to protect all attendees'' health has considerably accelerated research examining the most effective cooling strategies and the development of wearable cooling technology and real-time temperature monitoring. While these technological advances will aid the early identification of EHS cases, there are several potential ethical considerations for governing bodies and sports organisers. For example, the impact of recently developed cooling wearables on health and performance is unknown. Concerning improving athletic performance in a hot environment, there is uncertainty about this technology''s availability to all athletes. Furthermore, the real potential to obtain real-time core temperature data will oblige medical teams to make crucial decisions around their athletes continuing their competitions or withdraw. Therefore, the aim of this review is (1) to summarise the practical applications of the most novel cooling strategies/technologies for both safety (of athletes, spectators and workers) and performance purposes, and (2) to inform of the opportunities offered by recent technological developments for the early recognition and diagnosis of EHS. These opportunities are presented alongside several ethical dilemmas that require sports governing bodies to react by regulating the validity of recent technologies and their availability to all

The potential of blood flow restriction exercise to overcome Jetlag : important implications for Tokyo 2020

The decision taken by the International Olympic Committee (IOC) to host the Olympic Games this summer brings new challenges for event organisers and athletes. One such measure taken by the IOC is to mandate that athletes may not enter the Olympic Village more than five days before competing at the Games in order to prevent the spread of COVID-19. As a result, athletes from around the globe that are unable to make alternative plans will need to travel to Tokyo and acclimatize within only 5 days before their event. Of particular concern are the adverse health and performance effects elicited by flight dysrhythmia, also known as jetlag, on those athletes travelling to the Olympic Games across multiple times zones. Blood flow restriction (BFR) is a safe exercise mode that can potentially diminish the impact of jetlag on performance through its numerous beneficial physiological adaptations that overlap with those of other jetlag mitigation strategies. Experimental data are required to confirm this intriguing possibility. The present commentary aims to encourage more research into the effects of BFR training in conjunction with other strategies to overcome the effects of jetlag prior, during and after a long-haul flight on the subsequent performance of elite athletes, particularly during these difficult times of the COVID19 pandemic.https://www.minervamedica.it/en/journals/medicina-dello-sport2022-07-17hj2021Sports Medicin

Editorial:Protecting Olympic Participants from COVID-19 — The Trialled and Tested Process

The COVID-19 pandemic has created many challenges to ensure a safe environment for competitive sport. While modern medicine has already developed effective protocols for the treatment and prevention of the disease, there are serious concerns about hosting a sporting event of the scale of the Olympic Games, where more than 11¿000 athletes from over 200 nations are expected to participate. Accordingly, there have been many calls to cancel the Tokyo Olympic Games, also known as Tokyo 2020, in both the international press and the scientific literature. A recent perspective published in the New England Journal of Medicine (NEJM) highlights the complexity and risks of convening the Tokyo Olympic Games during the COVID-19 pandemic. Despite the many uncertainties, much has been learnt over the past 18 months and many policies trialled and tested to protect athletes during sports participation..

Recommendations for Face Coverings While Exercising During the COVID-19 Pandemic

In an effort to reduce transmission and number of infections of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 or COVID-19) virus, governments and official bodies around the world have produced guidelines on the use of face masks and face coverings. While there is a growing body of recommendations for healthcare professionals and the wider population to use facial protection in “enclosed spaces” where minimal distancing from other individuals is not possible, there is a dearth of clear guidelines for individuals undertaking exercise and sporting activity. The present viewpoint aims to propose recommendations for face coverings while exercising during the COVID-19 pandemic that consider physical distancing, the environment, the density of active cases associated with the specific sports activity, and the practical use of face coverings in order to reduce potential viral transmission. Recommendations are provided on the basis of very limited available evidence in conjunction with the extensive collective clinical experience of the authors and acknowledging the need to consider the likelihood of the presence of the SARS-CoV-2 in the general population. We recommend that face coverings should be used in any environment considered to be of a high or moderate transmission risk, where tolerated and after individual risk assessment. In addition, as national caseloads fluctuate, individual sporting bodies should consider up to date guidance on the use of face coverings during sport and exercise, alongside other preventative measures

Extremely short duration high intensity interval training substantially improves insulin action in young healthy males

Background: Traditional high volume aerobic exercise training reduces cardiovascular and metabolic disease risk but involves a substantial time commitment. Extremely low volume high-intensity interval training (HIT) has recently been demonstrated to produce improvements to aerobic function, but it is unknown whether HIT has the capacity to improve insulin action and hence glycemic control. Methods: Sixteen young men (age: 21 ± 2 y; BMI: 23.7 ± 3.1 kg·m-2; VO2peak: 48 ± 9 ml·kg-1·min-1) performed 2 weeks of supervised HIT comprising of a total of 15 min of exercise (6 sessions; 4-6 × 30-s cycle sprints per session). Aerobic performance (250-kJ self-paced cycling time trial), and glucose, insulin and NEFA responses to a 75-g oral glucose load (oral glucose tolerance test; OGTT) were determined before and after training. Results: Following 2 weeks of HIT, the area under the plasma glucose, insulin and NEFA concentration-time curves were all reduced (12%, 37%, 26% respectively, all P < 0.001). Fasting plasma insulin and glucose concentrations remained unchanged, but there was a tendency for reduced fasting plasma NEFA concentrations post-training (pre: 350 ± 36 v post: 290 ± 39 μmol·l-1, P = 0.058). Insulin sensitivity, as measured by the Cederholm index, was improved by 23% (P < 0.01), while aerobic cycling performance improved by ∼6% (P < 0.01). Conclusion: The efficacy of a high intensity exercise protocol, involving only ∼250 kcal of work each week, to substantially improve insulin action in young sedentary subjects is remarkable. This novel time-efficient training paradigm can be used as a strategy to reduce metabolic risk factors in young and middle aged sedentary populations who otherwise would not adhere to time consuming traditional aerobic exercise regimes

Commentaries on viewpoint : physiology and fast marathons

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