Areas at high-altitude, annually attract millions of tourists, skiers, trekkers, and climbers. If not adequately prepared and not considering certain ascent rules, a considerable proportion of those people will suffer from acute mountain sickness (AMS) or even from life-threatening high-altitude cerebral (HACE) or/and pulmonary edema (HAPE). Reduced inspired oxygen partial pressure with gain in altitude and consequently reduced oxygen availability is primarily responsible for getting sick in this setting. Appropriate acclimatization by slowly raising the hypoxic stimulus (e.g., slow ascent to high altitude) and/or repeated exposures to altitude or artificial, normobaric hypoxia will largely prevent those illnesses. Understanding physiological mechanisms of acclimatization and pathophysiological mechanisms of high-altitude diseases, knowledge of symptoms and signs, treatment and prevention strategies will largely contribute to the risk reduction and increased safety, success and enjoyment at high altitude. Thus, this review is intended to provide a sound basis for both physicians counseling high-altitude visitors and high-altitude visitors themselves.
The ability of physical activity to ameliorate cardiovascular disease and improve cardiovascular health is well accepted, but many aspects of the molecular mechanisms underlying these benefits are incompletely understood. Exercise increases the levels of reactive oxygen species (ROS) through various mechanisms. This triggers the activation of Nrf2, a redox-sensitive transcription factor activated by increases in oxidative stress. Activation of Nrf2 mitigates oxidative stress by increasing the nuclear transcription of many antioxidant genes while also mediating additional beneficial effects through the cytoprotective nature of Nrf2 signaling. Understanding the transcriptional patterns of Nrf2 caused by exercise can help in the design of pharmacological mimicry of the process in patients who are unable to exercise for various reasons.
Our aim was to conduct a narrative review about physical exercise and Corona Virus Disease 2019 (COVID-19). A literature search was completed crossing the keywords “COVID-19” and “physical exercise”, for a narrative review, and physical activity (PA), physical exercise, physical training, sport, physical fitness, for a systematic review; search strategy (Randomized Controlled Trial, in the last 1 year, English). The first search date was closed on 04/26/2020 and 06/26/2020. This strategy was chosen to assess the dynamics of scientific information production for the pandemic. In two months, an increase of 76%, from 12 (19.4%) to 50 (80.64%) COVID-19 articles (n = 62, 100%) was found. The main types of articles published were editorial articles (16.13%, n = 10 of 62 articles) and commentary (9.68%, n = 6 of 62 articles). The most frequent country of origin of the scientific production was the United States (12.90%, n = 8 of 62 articles), the United Kingdom (12.90%, n = 8 of 62 articles), and Brazil (11.29%, n = 7 of 62 articles). However, in 2020, there were only 2 relevant randomized controlled trials on the COVID-19 topic in the context of physical exercise. Scientific information production shows the concern of the PA science community to bring a solution to the increase in physical inactivity generated by the COVID-19 pandemic. Our findings show the dynamics of scientific production on the COVID-19, in a situation so unique such as a pandemic, denotes that the practice of PA is essential to improve and/or maintain physical and mental health.
Intrinsic factors such as leg length, arm length, flexibility and training history are factors that may be relevant to the optimisation of the individual bicycle configuration process. Bike fitting methods do not always take all these variables into account, and as yet there have been limited studies examining how these variables can affect the cyclist's position on the bicycle. The main aims of this study were to establish how individual anthropometrics, training history and flexibility may influence cyclists' freely chosen bicycle configuration, and to determine the full-body static flexion angles chosen by cyclists on the bicycle.
Fifty well-trained male cyclists were recruited for the study. A multivariate linear regression analysis was performed to predict the four main configurations of a bicycle (saddle height, saddle setback, handlebar reach and handlebar drop) based on individual anthropometrics, flexibility and training history. Average joint kinematic ranges for the knee (36°±7°) and elbow (19°±8°) joint supported previous recommendations. Hip (77°±5°) and shoulder (112°±7°) joint angles should be determined as true clinical joints.
Trochanteric leg length (p < 0.01), Knee Extension Angle test (p < 0.01) and mSchober test (p = 0.04) were significant predictors for determining saddle height. Hamstring flexibility can be used to predict handlebar drop (p = 0.01).
A cyclist who wishes to adopt a more aerodynamic position with an increased handlebar drop should aim to improve their hamstring flexibility.
The purpose of this study was to examine the effects of a 1-h downhill running exercise on the elbow flexor muscles’ neuromuscular functions. Seventeen adults (Control [CON]: n = 9; Experimental [EXP]: n = 8) completed this study. The CON rested for 30 min while the EXP performed the downhill running. Before, 10 min, 24 h, and 48 h after the interventions, dependent variables (knee extensor muscle soreness, elbow flexion and knee extension isometric strength, elbow flexion resting twitch and voluntary activation [VA], and the biceps surface electromyography [EMG] amplitude) were measured. Knee extensor muscle soreness was significantly greater in the EXP than the CON group following the intervention throughout the entire 48 h. This was accompanied by the greater decline in the knee extension strength in the EXP than the CON (mean ± SD: -6.9 ± 3.4% vs. 1.0 ± 3.2%, p = 0.044). The elbow flexion strength, VA, and EMG amplitude were not affected by the exercise. However, the decline of the elbow flexion resting twitch was greater in the EXP than the CON (−19.6 ± 6.3% vs. 8.7 ± 5.9%, p = 0.003). Therefore, the downhill running impaired the remote elbow flexor muscles at a peripheral level.
Sport-related concussion (SRC) is a common and increasingly recognised sport-related injury and accounts for between 1% and 9% of all cycling-specific injuries. Attention has been drawn to the difficulty in managing suspected SRC in a fast-paced sport such as road cycling, particularly the lack of an effective and time-efficient assessment protocol. A meeting on cycling SRC was convened in Harrogate, United Kingdom, in an attempt to resolve this problem. The aim was to agree on standard terminology, definitions, diagnostic protocols and return to play protocols for the various differing codes of cycle sport. Seven experts in the field of cycling medicine were invited to participate by the International Cycling Union and are the authors of this report. The panel recognised that the sport of cycling consists of varied disciplines, some of which provide a setting in which a sideline assessment is possible which is in line with the Berlin Consensus statement. However, other disciplines provide challenging circumstances where health care providers have limited access to participants and where participants are unable to discontinue participation and participate in sideline assessment. Consensus-based discipline-specific protocols and guidelines which recognise the limitations posed by these circumstances, but nevertheless, improve on the current situation specific to the sport of cycling are presented as a potential solution to the unique challenges posed by these cycling disciplines.
The World Health Organization released new guidelines on physical activity and sedentary behaviour in November 2020. This commentary summarises these guidelines, including the new elements. An evaluation of the guidelines for each specific sub-population is provided. Finally, as the author group includes physical activity researchers from four continents, we provide recommendations on how to support the implementation of the new guidelines.
Patellofemoral pain (PFP) is a common overuse condition seen in high-volume runners, such as military recruits. Exercise is commonly prescribed, with benefit, for the rehabilitation of individuals with PFP. However, a substantial number of individuals with the condition do not achieve an optimal outcome, suggesting the condition can be difficult and complex. Given the challenging nature of the condition, and the risk of developing PFP in high-volume runners, it seems logical to investigate options for injury prevention. Eccentric exercise has been useful in the prevention of some pathologies so its utility in preventing PFP should be explored. Current evidence regarding prevention programs for PFP are limited. Preventative exercise programs for PFP have not been well described or reported, and questions remain regarding their effectiveness. Based on available evidence or lack thereof, and known physiological and clinical effects of eccentric exercise, suggestions for integration of eccentric exercise into PFP prevention programs are offered. Eccentric exercise may be useful for PFP prevention from a theoretical framework however additional longitudinal cohort studies would be useful in determining its utility.