Altitude training has become an important training application for athletes due its potential for altering physiology and enhancing performance. This practice is commonly used by athletes, with a popular choice being the live high - train low approach. This model recommends that athletes live at high altitude (1250-3000 m), but train at low altitude or sea-level (0-1200 m). Exposure to altitude often leads to hypoxic stress and in turn stimulates changes in total haemoglobin mass, erythropoietin, and soluble transferrin receptors, which alter further underlying physiology. Through enhanced physiology, improved exercise performance may arise through enhancement of the oxygen transport system which is important for endurance events. Previous investigations into the effects of altitude training on exercise performance have been completed in a range of contexts, including running, cycling, swimming, and triathlon. Often following a LHTL altitude intervention, athletes realise improvements in maximal oxygen consumption capacity, time trial performance and peak power outputs. Although heterogeneity exists among LHTL methodologies, i.e., exposure durations and altitude ranges, we synthesised this data into kilometre hours, and found that the most common hypoxic doses used in LHTL interventions ranged from ∼578-687 km h. As this narrative review demonstrates, there are potential advantages to using altitude training to enhance physiology and improve performance for endurance athletes.

Clinical complications are not expected in current space missions; however, for future long-duration missions to the Moon and Mars, a new perspective may be needed - a more clinical approach. Different risks, both environmental, such as radiation, accidents, and biopsychological, including neurological problems, represent potential sources of subsequent neurocognitive deficits.
This study aims to review research studies published to this date in microgravity conditions using existing spaceflight neurocognitive assessment batteries. This study also discusses the different risks of neuropsychological impairment in spaceflight and the potential benefits of increasing the clinical validity of these tools with neurological clinical samples on Earth for future long-duration missions.
A PRISMA guidelines-based review of specialized literature on neurocognitive assessment batteries and human spaceflight was performed. Different factors including type of tool or battery used, sample size, mission duration, etc. were included in this review. After the scrutiny of 192 articles, a total of 27 studies were detailed in the review outcome.
Results showed that neuropsychological function research target has changed over the years, with working memory and perception studies being predominant in the 80s and 90s while reaction time being more frequent in recent research. We also found a lack of language-related research in microgravity and the predominance of two neurocognitive assessment batteries in microgravity research.
With this study, we want to emphasize the importance of increasing the clinical validity of neurocognitive or neuropsychological assessment tools to be used in space, especially in long-duration missions because in this type of mission the risk of suffering a brain injury or neurological condition increases due to multiple factors. Testing these tools with neurological clinical samples and using machine learning, predictive systems may help crews in early detection of potential clinical, neurological, or neurocognitive problems during these long-duration missions to Mars and beyond.

BACKGROUND: Human performance in classical ballet is a research field of growing interest in the past decades. Technology used to acquire data in human movement sciences has evolved, and is specifically being applied to evaluate ballet movements to better understand dancers\' profiles. We aimed to systematically review sensing technologies that were used to extract data from dancers, in order to improve knowledge regarding the performance of ballet movements through quantification.
METHODS: PubMed, MEDLINE, EMBASE, and Web of Science databases were accessed through 2020. All studies that used motor control tools to evaluate classical ballet movements, and possible comparisons to other types of dance and sports movements were selected. Pertinent data were filled into a customized table, and risk of bias was carefully analyzed.
RESULTS: Eighty studies were included. The majority were regarding classical ballet and with pre-professional dancers. Forty-four studies (55%) used two or more types of technology to collect data, showing that motion capture technique, force plates, electromyography, and inertial sensors are the most frequent ways to evaluate ballet movements.
CONCLUSIONS: Research to evaluate ballet movements varies greatly considering study design and specific intervention characteristics. Combining two or more types of technology may increase data reliability and optimize the characterization of ballet movements. A lack of studies addressing muscle-brain interaction in dancers were observed, and given the potential of novel insights, further studies in this field are warranted. Finally, using quantitative tools opens the perspective of defining what is considered an elite dancer.

The effects of short sprint interval training (sSIT) with efforts of ≤10 s on maximal oxygen consumption (V̇O2 max), aerobic and anaerobic performances remain unknown. To verify the effectiveness of sSIT in physically active adults and athletes, a systematic literature search was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The databases PubMed/MEDLINE, ISI Web of Science, and SPORTDiscus were systematically searched on May 9, 2020, and updated on September 14, 2021. Inclusion criteria were based on PICO and included healthy athletes and active adults of any sex (≤40 years), performing supervised sSIT (≤10 s of \"all-out\" and non-\"all-out\" efforts) of at least 2 weeks, with a minimum of 6 sessions. As a comparator, a non-sSIT control group, another high-intensity interval training (HIIT) group, or a continuous training (CT) group were required. A total of 18 studies were deemed eligible. The estimated SMDs based on the random-effects model were -0.56 (95% CI: -0.79, -0.33, p < 0.001) for V̇O2 max, -0.43 (95% CI: -0.67, -0.20, p < 0.001) for aerobic performance, and -0.44 (95% CI: -0.70, -0.18, p < 0.001) for anaerobic performance after sSIT vs. no exercise/usual training. However, there were no significant differences (p > 0.05) for all outcomes when comparing sSIT vs. HIIT/CT. Our findings indicate a very high effectiveness of sSIT protocols in different exercise modes (e.g., cycling, running, paddling, and punching) to improve V̇O2 max, aerobic, and anaerobic performances in physically active young healthy adults and athletes.

Human performance optimization of tactical personnel requires accurate, meticulous, and effective monitoring of biological adaptations and systemic recovery. Due to an increased understanding of its importance and the commercial availability of assessment tools, the use of heart rate variability (HRV) to address this need is becoming more common in the tactical community. Measuring HRV is a non-invasive, practical method for objectively assessing a performer\'s readiness, workload, and recovery status; when combined with additional data sources and practitioner input, it provides an affordable and scalable solution for gaining actionable information to support the facilitation and maintenance of operational performance. This narrative review discusses the non-clinical use of HRV for assessing, monitoring, and interpreting autonomic nervous system resource availability, modulation, effectiveness, and efficiency in tactical populations. Broadly, HRV metrics represent a complex series of interactions resulting from internal and external stimuli; therefore, a general overview of HRV applications in tactical personnel is discussed, including the influence of occupational specific demands, interactions between cognitive and physical domains, and recommendations on implementing HRV for training and recovery insights into critical health and performance outcomes.

Although there is a plethora of information available regarding the impact of nutrition on exercise performance, many recommendations are based on male needs due to the dominance of male participation in the nutrition and exercise science literature. Female participation in sport and exercise is prevalent, making it vital for guidelines to address the sex-specific nutritional needs. Female hormonal levels, such as estrogen and progesterone, fluctuate throughout the mensural cycle and lifecycle requiring more attention for effective nutritional considerations. Sex-specific nutritional recommendations and guidelines for the active female and female athlete have been lacking to date and warrant further consideration. This review provides a practical overview of key physiological and nutritional considerations for the active female. Available literature regarding sex-specific nutrition and dietary supplement guidelines for women has been synthesized, offering evidenced-based practical information that can be incorporated into the daily lives of women to improve performance, body composition, and overall health.

Cranial electrotherapy stimulation (CES) is a neuromodulation tool used for treating several clinical disorders, including insomnia, anxiety, and depression. More recently, a limited number of studies have examined CES for altering affect, physiology, and behavior in healthy, non-clinical samples. The physiological, neurochemical, and metabolic mechanisms underlying CES effects are currently unknown. Computational modeling suggests that electrical current administered with CES at the earlobes can reach cortical and subcortical regions at very low intensities associated with subthreshold neuromodulatory effects, and studies using electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) show some effects on alpha band EEG activity, and modulation of the default mode network during CES administration. One theory suggests that CES modulates brain stem (e.g., medulla), limbic (e.g., thalamus, amygdala), and cortical (e.g., prefrontal cortex) regions and increases relative parasympathetic to sympathetic drive in the autonomic nervous system. There is no direct evidence supporting this theory, but one of its assumptions is that CES may induce its effects by stimulating afferent projections of the vagus nerve, which provides parasympathetic signals to the cardiorespiratory and digestive systems. In our critical review of studies using CES in clinical and non-clinical populations, we found severe methodological concerns, including potential conflicts of interest, risk of methodological and analytic biases, issues with sham credibility, lack of blinding, and a severe heterogeneity of CES parameters selected and employed across scientists, laboratories, institutions, and studies. These limitations make it difficult to derive consistent or compelling insights from the extant literature, tempering enthusiasm for CES and its potential to alter nervous system activity or behavior in meaningful or reliable ways. The lack of compelling evidence also motivates well-designed and relatively high-powered experiments to assess how CES might modulate the physiological, affective, and cognitive responses to stress. Establishing reliable empirical links between CES administration and human performance is critical for supporting its prospective use during occupational training, operations, or recovery, ensuring reliability and robustness of effects, characterizing if, when, and in whom such effects might arise, and ensuring that any benefits of CES outweigh the risks of adverse events.

Sleep inertia is a measurable decline in cognition some people experience upon and following awakening. However, a systematic review of the current up to date evidence of audio as a countermeasure has yet to be reported. Thus, to amend this gap in knowledge, the authors conducted this systematic review beginning with searches in three primary databases for studies published between the inception date of each journal and the year 2020. Search terms contained \"Sleep Inertia\" paired with: \"Sound\"; \"Noise\"; \"Music\"; \"Alarm\"; \"Alarm Tone\"; \"Alarm Sound\"; \"Alarm Noise\"; \"Alarm Music\"; \"Alarm Clock\"; \"Fire Alarm\", and \"Smoke Alarm\". From 341 study results, twelve were identified for inclusion against a priori conditions. A structured narrative synthesis approach generated three key auditory stimulus themes-(i) Noise, (ii) Emergency tone sequences; Voice Alarms and Hybrids, and (iii) Music. Across themes, participants have been assessed in two situational categories: emergency, and non-emergency awakenings. The results indicate that for children awakening in emergency conditions, a low pitch alarm or voice warnings appear to be more effective in counteracting the effects of sleep inertia than alarms with higher frequencies. For adults abruptly awakened, there is insufficient evidence to support firm conclusions regarding alarm types and voice signals. Positive results have been found in non-emergency awakenings for musical treatments in adults who preferred popular music, and alarms with melodic qualities. The results observed reflect the potential for sound, voice, and musical treatments to counteract sleep inertia post-awakening, and emphasize the requirements for further research in this domain.

In part 1 of this article, we describe an approach and methodology that bridges 2 worlds: the internal, subjective experience of emotions and thoughts, and the external world of brain electrical activity. Using a novel event-related brain activation imaging method, we demonstrate that within single trials, short-term mental processes, on the order of 100 ms, can be clearly related to observed brain activation in controlled experiments. We use an ipsative assessment validation process that combines self-report with real-time EEG recordings to provide a combined picture of both the mental and the brain activity, during short-term reactions, emotions, and decisions regarding controlled information. Part 2 provides a detailed description of the emerging emotional decision-making model.

In this report, we integrate the principles described in part 1 and describe an operational model for emotional decision making that incorporates brain activation data along with subjective experience correlates. This model takes the form of a state machine that carries out transitions between a finite set of 16 possible states of emotional and decision-making response. By considering a 4 × 4 grid of possible states based on left and right activation, in primary (sensation) and secondary (perception/comprehension) response, the range of responses is completely specified. The transition probabilities within this repertoire of possible response states can be used to characterize an individual (or any system) in terms of its likelihood to respond in a particular fashion. The possible value of this model in psychiatry, psychology, and counseling is introduced and discussed.