Braid Groups on Triangulated Surfaces and Singular Homology

Let $\Sigma_g$ denote the closed orientable surface of genus $g$ and fix an arbitrary simplicial triangulation of $\Sigma_g$. We construct and study a natural surjective group homomorphism from the surface braid group on $n$ strands on $\Sigma_g$ to the first singular homology group of $\Sigma_g$ with integral coefficients. In particular, we show that the kernel of this homomorphism is generated by canonical braids which arise from the triangulation of $\Sigma_g$. This provides a simple description of natural subgroups of surface braid groups which are closely tied to the homology groups of the surfaces $\Sigma_g$

Pedaling time variability is increased in dropped riding position

Variability of cycle-to-cycle duration during a pedaling task is probably related to the rhythmic control of the lower limb muscles as in gait. Although walking variability has been extensively studied for its clinical and physiological implications, pedaling variability has received little attention. The present contribution determines the variability of the cycling time during a 10-min exercise as a function of upper body position. Nine healthy males were required to pedal on cycle-ergometer at a self-selected speed for 10 min in two different upper body positions [hands on upper handlebars (UP) or lower handlebars (DP)]. Time domain measures of cycling variability [total standard deviation (SDtot), mean standard deviation cycle-to-cycle intervals over 100 cycles (SD100), standard deviation of the average cycle-to-cycle intervals over 100 cycles (SDA100)] were measured. Moreover, the same time domain measures were also calculated for heart rate in order to discriminate possible involvements of autonomic regulation. Finally, the structure of the cycle variations has been analyzed in the framework of deterministic chaos calculating the maximum Lyapunov exponents. Significant increases in cycle-to-cycle variability were found for SDtot, SD100 in DP compared to UP, whereas cardiac parameters and other cycling parameters were not changed in the two positions. Moreover, the maximum Lyapunov exponent was significantly more negative in DP. The results suggest that small perturbations of upper body position can influence the control of cycling rhythmicity by increasing the variability in a dissipative deterministic regimen

Gait alterations during constant pace treadmill racewalking

Racewalking is an Olympic event requiring great endurance, and racewalkers often use treadmills in training because of the benefits of having a flat, unchanging surface where pace judgment can be learned, and because inclement weather can be avoided. The effects of fatigue associated with racewalking on a treadmill have not been studied, and could be informative with regard to the maintenance of legal technique. The aim of this study was to measure key gait variables during a physically demanding treadmill racewalk. Fourteen international racewalkers completed 10 km on an instrumented treadmill at a pace equivalent to 103% of their recent best time. Spatiotemporal and ground reaction force data were recorded at four distances. High-speed videography data were simultaneously recorded to analyze changes in knee angle between the early and late stages. Increases in step length and corresponding decreases in cadence were found, although the small changes were not considered meaningful. There was also a small increase in flight time and a small decrease in push-off force. There were no other significant changes for any other variables (including knee angles). The increase in flight time might be important given that racewalkers are not permitted a visible loss of contact and suggests that fatiguing sessions on a treadmill can lead to the adoption of non-legal technique. However, this disadvantage of treadmill training can be negated if the coach scrutinizes the athlete throughout the session, and overall the consistent technique used is of benefit with regard to learning correct form and pacing ability

Effect of three technical arms swings on the elevation of the center of mass during a standing back somersault

Arms swing during standing back somersaults relates to three different “gymnastics schools”, each is considered “optimal” by its adepts. In the three cases, technical performance, elevation and safety differ. Therefore, the aim of this study was to compare the mechanical variables of three different arms swing techniques in the performance of a standing back tucked somersault. Five high-level male gymnasts (age: 23.17±1.61 yrs; body height: 1.65±0.05 m; body mass: 56.80±7.66 kg) randomly performed standing somersaults under three conditions, each following a different arms’ swing technical angle (270°, 180° and 90°). A force plate synchronized with a three dimensional movement analysis system was used to collect kinetic and kinematic data. Significant differences were observed between somersaults’ performance. The back somersault performed with 270° arms swing showed the best vertical displacement (up to 13.73%), while the back somersaults performed with 180° arms swing showed a decrease in power (up to 22.20%). The back somersault with 90° arms swing showed the highest force (up to 19.46%). Considering that the higher elevation of the centre of mass during the flight phase would allow best performance and lower the risk of falls, this study demonstrated that optimal arms’ swing technique prior to back tucked somersault was 270°

Sport and health science: interdisciplinary approaches to modern challenges

Background: Sport and health science are undergoing a transformative shift driven by interdisciplinary approaches, technological innovations, and data-driven strategies. Sources of data: This invited editorial explores key advancements in precision athletic monitoring, holistic well-being, population health initiatives, and innovative training and rehabilitation techniques. The integration of wearable technology, real-time analytics, and psychological interventions enables more personalized and effective strategies to optimize performance and promoting overall health. Additionally, the role of physical activity in mitigating lifestyle-related diseases underscores the importance of tailored public health initiatives. Areas of agreement: Current consensus in sport and health science highlights that interdisciplinary collaboration-blending physiology, psychology, nutrition, and data analytics-significantly improves both athletic performance and public health outcomes. This progress is driven by precision monitoring technologies, holistic well-being strategies, innovative training methods, and a shared commitment to ethical standards ensuring equitable, responsible application of new health, and performance innovations. Areas of controversy: As the field progresses, ethical considerations regarding data privacy, accessibility, and equitable application of emerging technologies remain central. Growing points: Future directions include leveraging artificial intelligence, machine learning, and big data to refine personalized interventions, ensuring that both athletic and public health advancements are sustainable and inclusive. Areas timely for developing research: Emerging research in sport and health science focuses on harnessing artificial intelligence, machine learning, and big data to develop predictive models and personalized interventions, while tailoring physical activity programmes to diverse population needs based on age, gender, socioeconomic, and cultural factors. Simultaneously, priorities include advancing psychological and mindfulness-based strategies in athletic care, integrating cutting-edge rehabilitation technologies, promoting inclusive public health frameworks for ageing and chronically ill populations, and establishing ethical guidelines for the responsible use of innovative performance and health technologies

I.S.Mu.L.T - Rotator cuff tears guidelines

Despite the high level achieved in the field of shoulder surgery, a global consensus on rotator cuff tears management is lacking. This work is divided into two main sessions: in the first, we set questions about hot topics involved in the rotator cuff tears, from the etiopathogenesis to the surgical treatment. In the second, we answered these questions by mentioning Evidence Based Medicine. The aim of the present work is to provide easily accessible guidelines: they could be considered as recommendations for a good clinical practice developed through a process of systematic review of the literature and expert opinion, in order to improve the quality of care and rationalize the use of resources

I.S.Mu.L.T. Achilles Tendon Ruptures Guidelines

This work provides easily accessible guidelines for the diagnosis, treatment and rehabilitation of Achilles tendon ruptures. These guidelines could be considered as recommendations for good clinical practice developed through a process of systematic review of the literature and expert opinion, to improve the quality of care for the individual patient and rationalize the use of resources. This work is divided into two sessions: 1) questions about hot topics; 2) answers to the questions following Evidence Based Medicine principles. Despite the frequency of the pathology andthe high level of satisfaction achieved in treatment of Achilles tendon ruptures, a global consensus is lacking. In fact, there is not a uniform treatment and rehabilitation protocol used for Achilles tendon ruptures

The Balancing Act: Work Environment Issues for Women with Children in Student Affairs

Increasingly in the past two decades, student affairs work at American\u27s universities has been undertaken by women. This work with the co-curricular life of the students in higher education requires administrators at all levels to have a flexible schedule with the ability to commit evenings and weekends to their work. Challenges for academe and for women in the profession have emerged as more women enter the field. One of the most problematic areas is the retention of highly educated and experienced female administrators once they have children. Workplace environment, including work schedule, job demands and employer support, have been suggested as reasons why many working mothers leave the student affairs profession or are unable to advance to the highest levels of administration. To explore these problems in more detail, this study collected data from 35 working mothers in student affairs careers at universities in California. A Delphi process enabled the study participants, through four rounds of questionnaires, to arrive at consensus on the most important work environment issues affecting working mothers in both positive and negative ways. Strategies for both addressing work-family balance issues in the workplace and for seeking work environments which support work-family balance were identified. The finds of the study revealed that working mothers in student affairs value a flexible work schedule with little or no weekend or evening obligations, a job description which includes manageable responsibilities with flexibility for where and when to accomplish the work, and a supportive supervisor. Recommendations were offered for working mothers in the profession and for managers and supervisors who would like to retain these committed, experienced and talented professionals