The ergogenic effects of acute carbohydrate feeding on endurance performance: a systematic review, meta-analysis and meta-regression.

A systematic review with meta-analysis was conducted to analyze the effect of carbohydrate (CHO) intake during exercise and some variables that could moderate this effect on endurance performance. We included 136 studies examining the effect of CHO ingestion during endurance exercise in the meta-analysis. The overall effect on performance showed a significant increase after CHO intake compared to the placebo/control groups. A larger effect of CHO consumption is observed in time to exhaustion than in time trials performance test. Moreover, the effectiveness of CHO supplementation was greater the longer the duration of the events. Also, there seems to be a higher effect of CHO intake in lower trained than in higher trained participants. In contrast, the magnitude of performance change of CHO intake is not affected by the dosage, ergometer used, the type of intake of the CHO ingestion and the type of CHO. In addition, a lower rate of perceived exertion and higher power and heart rate are significantly associated with the ingestion of CHO during endurance exercise. These results reinforce that acute CHO feeding is an effective strategy for improving endurance performance, especially, in less trained subjects participating in time to exhaustion tests of longer durations.

Comparison of Visual Skills between Federated and Non-Federated Athletes.

Background: To perform motor tasks, athletes must gather a considerable amount of visual information quickly. Evidence shows that visual skills vary between athletes and non-athletes, and impact athletic performance. However, there is no scientific evidence suggesting that there are any differences between the visual skills of federated and non-federated athletes. As such, the objective of this paper was to compare how visual skills influence the sports performance of federated and non-federated athletes, respectively. Methods: A visual examination has been conducted on a total of 52 athletes between 18 and 37 years of age. The COI-Sport Vision system screen (International Optometry Center, Madrid, Spain) was used to examine static visual acuity, dynamic visual acuity, contrast sensitivity, stereopsis, fixation disparity, visual memory, identification, anticipation time, peripheral awareness, and hand-eye coordination. Results: On average, federated athletes train more hours per day than non-federated athletes (1.4 ± 0.8) (p = 0.046). A significant correlation was observed between the average time of visual memory (ß = −0.0683, p < 0.001), the average time of anticipation (ß = 0.006, p = 0.009), the average time of peripheral awareness (ß = 0.026, p = 0.002), hand-eye coordination (ß = 0.028, p = 0.004), dynamic visual acuity (ß = 0.055, p < 0.001), and the number of training hours. Conclusion: Results suggest that federated athletes are more concerned about their ocular health. Nonetheless, no differences were found in the oculomotor skills of both groups. Further investigation is required to consider each sport discipline individually.

Validity of detrended fluctuation analysis of heart rate variability to determine intensity thresholds in elite cyclists.

Background: The evaluation of performance in endurance athletes and the subsequent individualisation of training is based on the determination of individual physiological thresholds during incremental tests. Gas exchange or blood lactate analysis are usually implemented for this purpose, but these methodologies are expensive and invasive. The short-term scaling exponent alpha 1 of detrended Fluctuation Analysis (DFA-α1) of the Heart Rate Variability (HRV) has been proposed as a non-invasive methodology to detect intensity thresholds. Purpose: The aim of this study is to analyse the validity of DFA-α1 HRV analysis to determine the individual training thresholds in elite cyclists and to compare them against the lactate thresholds. Methodology: 38 male elite cyclists performed a graded exercise test to determine their individual thresholds. HRV and blood lactate were monitored during the test. The first (LT1 and DFA-α1-0.75, for lactate and HRV, respectively) and second (LT2 and DFA-α1-0.5, for lactate and HRV, respectively) training intensity thresholds were calculated. Then, these points were matched to their respective power output (PO) and heart rate (HR). Results: There were no significant differences (p > 0.05) between the DFA-α1-0.75 and LT1 with significant positive correlations in PO (r = 0.85) and HR (r = 0.66). The DFA-α1-0.5 was different against LT2 in PO (p = 0.04) and HR (p = 0.02), but it showed significant positive correlation in PO (r = 0.93) and HR (r = 0.71). Conclusions: The DFA1-a-0.75 can be used to estimate LT1 non-invasively in elite cyclists. Further research should explore the validity of DFA-α1-0.5.HighlightsThe power and heart rate values derived from the DFA-α1-0.75 threshold showed high levels of validity and agreement when they were compared against the first lactate threshold.The second lactate threshold and the DFA-α1-0.5 were different (p < 0.05) but showed high levels of correlation.The detrended fluctuation analysis is a valid method to estimate the first lactate threshold and more studies are needed to verify its validity with the second lactate threshold.

Autonomic stress response of physiotherapy student in the different scenarios of an objective structured clinical examination.

The aim of the present research was to analyse modifications in the autonomic stress response of Physiotherapy students undergoing a 12-scenario Objective Structured Clinical Evaluation (OSCE). A total of 86 last year students of the Physiotherapy bachelor's degree (27.29 years (SD = 6.66); 36 females and 50 males) randomly assigned were monitored during the complete OSCE to measure heart rate variability (HRV) in temporal, frequency, and non-linear domains. The HRV analysed showed a large anticipatory stress response of students maintained during the entire evaluation. The stress response varied regarding OSCE station complexity and demands and the highest sympathetic response was not found in higher emotional scenarios.The autonomic modulation monitoring allows teachers to design OSCE scenarios more adapted to the students, limiting the effect of the stress response to allow a better performance.

Acute Effects of Whole-Body Electromyostimulation during a Single Maximal Strength Training Session.

Whole-body electromyostimulation (WB-EMS) training is effective in improving training adaptation. However, WB-EMS may have side effects and contraindications that can lead to excessive muscle damage and physiological impairment. This randomized crossover study aimed to analyze the acute effects of WB-EMS on muscle damage, autonomic modulation and performance during a single maximal strength session in physically active participants. Twenty healthy and physically active participants randomly performed three maximal strength training sessions (90% 1RM) consisting of bench presses and squat exercises, with a continuous stimulus, a coordinated stimulus with concentric and eccentric phases, and without WB-EMS. Data showed no significant differences between the trials for muscle damage (blood creatine kinase levels), lactate blood levels and performance after exercise. Likewise, the heart rate, blood oxygen saturation and the rate of perceived exertion were similar during exercise between trials. The heart rate variability analysis also showed a similar autonomic response among the trials. Training with WB-EMS seemed to be safe at the observed time intervals while offering a stimulus similar to regular training in physically active participants, regardless of the delivery of the electrical stimuli. More studies are needed to assess the effectiveness of WB-EMS in improving exercise adaptations during training programs.

Central and Peripheral Fatigue in Physical Exercise Explained: A Narrative Review.

The study of the origin and implications of fatigue in exercise has been widely investigated, but not completely understood given the complex multifactorial mechanisms involved. Then, it is essential to understand the fatigue mechanism to help trainers and physicians to prescribe an adequate training load. The present narrative review aims to analyze the multifactorial factors of fatigue in physical exercise. To reach this aim, a consensus and critical review were performed using both primary sources, such as scientific articles, and secondary ones, such as bibliographic indexes, web pages, and databases. The main search engines were PubMed, SciELO, and Google Scholar. Central and peripheral fatigue are two unison constructs part of the Integrative Governor theory, in which both psychological and physiological drives and requirements are underpinned by homeostatic principles. The relative activity of each one is regulated by dynamic negative feedback activity, as the fundamental general operational controller. Fatigue is conditioned by factors such as gender, affecting men and women differently. Sleep deprivation or psychological disturbances caused, for example, by stress, can affect neural activation patterns, realigning them and slowing down simple mental operations in the context of fatigue. Then, fatigue can have different origins not only related with physiological factors. Therefore, all these prisms must be considered for future approaches from sport and clinical perspectives.

Ready for Combat, Psychophysiological Modifications in a Close-Quarter Combat Intervention After an Experimental Operative High-Intensity Interval Training.

ABSTRACT: Tornero-Aguilera, JF, Fernandez-Elias, VE, and Clemente-Suárez, VJ. Ready for combat, psychophysiological modifications in a close-quarter combat intervention after an experimental operative HIIT. J Strength Cond Res 36(3): 732-737, 2022-This study aimed to analyze the effect of an experimental operative high-intensity interval training (HIIT) program on the psychophysiological response of soldiers in a close-quarter combat (CQC) intervention. The psychophysiological response of 22 professional soldiers in a CQC before and after an experimental 2-week operative HIIT was analyzed. Training intervention produced a significant increase in blood lactate, isometric hand-grip strength, perceived stress, rates of perceived exertion, anxiety response, heart rate, and autonomic sympathetic modulation and a significant decrease in cortical arousal requirements. An experimental operative high-intensity interval training produced an increase on the psychophysiological operativity for CQC scenarios, increasing the sympathetic and physiological response and decreasing the cortical arousal requirement of soldiers.

Implications of surgical mask use in physical education lessons.

COVID-19 is being a huge challenge for education systems. Mandatory use of face masks in presential classes may lead to psychophysiological impairment of students, which affect lessons. Thus, the aim of the present research was to analyze the effect of mask use in basal psychophysiological status of physical education students prior to a physical education lesson. We analyzed 72 physical education students in two moments prior to two physical education lessons with 48 h between them. Blood oxygen saturation, body, temple and face temperatures, perceived stress and exertion, and heart rate variability were measured. Results showed that the use of surgical masks in physical education students produced a significant increase on subjective stress perception, sympathetic modulation, cardiovascular response, face, and temple temperature while decreasing blood oxygen saturation. We concluded that the use of surgical masks by physical education students induce modifications on the organic status, which could represent a handicap compromising the academic objectives of physical education lessons. This information can help teachers design efficient physical education lessons.

Psychophysiological response of military pilots in different combat flight maneuvers in a flight simulator.

OBJECTIVE: To analyze the psychophysiological response during takeoff, landing, air-air attack and air-ground attack maneuvers. METHODS: A total of 11 expert pilots (age=33.36 (5.37)) from the Spanish Air Force participated in this cross-sectional study. Participants had to complete in a flight simulator the following missions: 1) takeoff; 2) Air-air attack; 3) Air-Ground attack, and 4) Landing. The electroencephalographic activity (EEG) and heart rate variability (HRV) were collected during all these maneuvers. RESULTS: Significant higher values of theta (during takeoff, air-air attack and air-ground attack) EEG power spectrum were obtained when compared to baseline. Significant difference in the P3 scalp location was observed between landing and takeoff maneuvers in the beta EEG power spectrum. Furthermore, significant lower values of HRV were obtained during takeoff, landing, air-air attack and air-ground attack when compared to baseline values. Also, landing showed a higher sympathetic response when compared to takeoff maneuver. CONCLUSION: Takeoff, landing, air-air attack or air-ground attack maneuvers performed in a flight simulator produced significant changes in the electroencephalographic activity and autonomic modulation of professional pilots. Beta EEG power spectrum modifications suggest that landing maneuvers induced more attentional resources than takeoff. In the same line, a reduced HRV during landing was obtained when compared to takeoff. These results should be considered to training purposes.

Gender, Anxiety, and Legitimation of Violence in Adolescents Facing Simulated Physical Aggression at School.

We analyzed gender and anxiety differences in middle school students facing a physical peer aggression situation. The participants were 1147 adolescents aged between 12 and 18 years (male: n = 479; female: n = 668) who watched a 12 s animation representing the situation and filled out a questionnaire to analyze the legitimation of violent behaviors and anxiety levels. We registered their decisions to solve the situation using a categorical scale that included assertive, avoidant, aggressive, submissive, and supportive behaviors. Gender was not associated with the adolescent's behaviors in facing a simulated peer aggression situation. However, male teenagers tended to perceive adults as sanctioners and neutrals; those who used the diffusion of responsibility and dehumanization to justify their behavior also showed a higher state of anxiety. Female teenagers who expected legitimation from their peers, presented higher anxiety as well. Educational interventions may use these results, helping adolescents to understand that their acts have substantial implications in the lives of others. It is essential to develop group interventions that modify how adolescents manage their conflicts and change gender stereotypes that significantly impact health. We highlight the need for linking families in educational programs facing the challenges of transforming the legitimization of violence in parental practices.

Impact of Real and Simulated Flights on Psychophysiological Response of Military Pilots.

OBJECTIVE: The present research aimed to analyse the autonomic, anxiety, perceived exertion, and self-confidence response during real and simulated flights. METHODS: This cross-sectional study participated 12 experienced male pilots (age = 33.08 (5.21)) from the Spanish Air Force. Participants had to complete a real and a simulated flight mission randomly. The heart rate variability (HRV), anxiety, self-confidence, and rating of perceived exertion were collected before and after both manoeuvres, and HRV was also collected during both simulated and real flights. RESULTS: When studying the acute effects of real and simulated flights, the mean heart rate, the R-to-R interval, the cognitive anxiety and the perceived exertion were significantly impacted only by real flights. Furthermore, significant differences in the mean heart rate and RR interval were found when compared to the acute effects of real and simulated flights (with higher acute effects observed in real flights). Additionally, when compared the HRV values during simulated and real flights, significant differences were observed in the RR and heart rate mean (with lower RR interval and higher heart rate mean observed during real flights). CONCLUSION: Real flights significantly reduced the RR interval and cognitive anxiety while increased the heart rate mean and the rating of perceived exertion, whereas simulated flights did not induce any significant change in the autonomic modulation.

Psychophysiological respond in a swimming ultra-endurance event.

BACKGROUND: Ultra-endurance events under critical environmental conditions represent unique stress, resulting in acute marked adaptations to the cardiovascular, respiratory, metabolic and neuromuscular systems of the organism. In line with this, no studies in swimming events were found thus far. METHODS: This research aimed to analyze the psychophysiological response of swimmers in an ultra-endurance swimming event. Changes in the rate of perceived exertion, blood lactate concentration, 1000m swimming time and cortical arousal were measured in 19 male volunteer swimmers (28.0±5.6 years; 175.0±7.9 cm; 70.1±7.8 kg) in 3 moments during a 24h swimming event. RESULTS: We found a significant increase in lactate concentration after series 1, decreasing the values in series 2 and series 3. Cortical arousal decreased significantly in series 3 respect the basal sample. Rate of perceived exertion significantly increased in the swimming ultra-endurance event and 1000m swimming time was maintained during the series analyzed. CONCLUSIONS: An ultra-endurance swimming event produced an increase in blood lactate concentration and rated of perceived exertion and a decrease in cortical arousal, not affecting average swimming velocity along the event.

Airsoft: an efficient and motivating cardiovascular training choice.

BACKGROUND: Obesity and sedentarism have reached pandemic levels, postulating World Health Organization physical exercise as an important key factor for the prevention and treatment. In order to find a motivating and effective physical activity, we conducted this research intending to analyze the physiological and mechanical demands of an airsoft game. METHODS: Cardiovascular and mechanical activity were analyzed by heart rate monitors and GPS in 32 sedentary subjects (27.3±6.2 years; 26.3±7.9 BMI). RESULTS: Participants performed moderate to vigorous aerobic intensity for 3 hours and 20 min of which 55.2% was between 60-70% of their maximal heart rate and 14.2% above 70% of it, turned into distance 9.5 km of which 91.5% was moderate and 8.5% vigorous intensity. CONCLUSIONS: A single airsoft game performed by sedentary subject exceed the international recommendation of physical activity and weekly physical activity of US adults' citizens. This motivating and outdoor activity is an effective alternative to increase the population's physical activity levels.

Corrigendum: Psychophysiological Patterns Related to Success in a Special Operation Selection Course.

[This corrects the article DOI: 10.3389/fphys.2019.00867.].

The effect of final dissertation defense language, native vs. non-native, in the psychophysiological stress response of university students.

The objective of this study was to analyze the effect of final dissertation defense language in the autonomic stress response and cortical arousal of Physiotherapy students. We analysed in 110 students divided in 2 groups: native language (83) and non-native language (27), the autonomic stress response in four different moments of the dissertation defense; the cortical arousal and subjective perception of distress before and after the dissertation; and academic performance perception of students and the real performance obtained. Results showed a high sympathetic modulation at the beginning of the evaluation, which was maintained until the end of the evaluation in both groups. In addition, no decrease in cortical activity was found, possibly due to the short time of exposure to the stressful event. The final dissertation defense of Physiotherapy students produces an anticipatory anxiety response and a maintained high sympathetic nervous system activation during the defense, not negatively affecting cortical arousal, regardless of defending in native or non-native language.

Psychophysiological stress response of physiotherapy last year students in his final degree dissertation.

Final dissertation is considered one of the most stressful situations in university studies, but the stress response and its incidence in academic achievement is poor knowledge. The aim of the present research was to analyze the effect of the psychophysiological stress response of physiotherapy last year students in his final degree dissertation performance. We analyzed the heart rate variability (HRV) of 110 volunteers during their final degree dissertation to evaluate the autonomic stress response. Results showed a large anticipatory anxiety response of students prior to the final degree dissertation and a no habituation response, since low HRV results were found before and during the final degree dissertation. Only after the dissertation, the HRV increased. No relationship between autonomic modulation and the dissertation academic achievement were found. Final degree dissertation in physiotherapy students, produce a large anticipatory anxiety response. Autonomic modulation parameters do not present relationship with the final degree dissertation performance.

Warming Up Before a 20-Minute Endurance Effort: Is It Really Worth It?

PURPOSE: To analyze the effects of different warm-up protocols on endurance-cycling performance from an integrative perspective (by assessing perceptual, neuromuscular, physiological, and metabolic variables). METHODS: Following a randomized crossover design, 15 male cyclists (35 [9] y; peak oxygen uptake [VO2peak] 66.4 [6.8] mL·kg-1·min-1) performed a 20-minute cycling time trial (TT) preceded by no warm-up, a standard warm-up (10 min at 60% of VO2peak), or a warm-up that was intended to induce potentiation postactivation (PAP warm-up; 5 min at 60% of VO2peak followed by three 10-s all-out sprints). Study outcomes were jumping ability and heart-rate variability (both assessed at baseline and before the TT), TT performance (mean power output), and perceptual (rating of perceived exertion) and physiological (oxygen uptake, muscle oxygenation, heart-rate variability, blood lactate, and thigh skin temperature) responses during and after the TT. RESULTS: Both standard and PAP warm-up (9.7% [4.7%] and 12.9% [6.5%], respectively, P < .001), but not no warm-up (-0.9% [4.8%], P = .074), increased jumping ability and decreased heart-rate variability (-7.9% [14.2%], P = .027; -20.3% [24.7%], P = .006; and -1.7% [10.5%], P = .366). Participants started the TT (minutes 0-3) at a higher power output and oxygen uptake after PAP warm-up compared with the other 2 protocols (P < .05), but no between-conditions differences were found overall for the remainder of outcomes (P > .05). CONCLUSIONS: Compared with no warm-up, warming up enhanced jumping performance and sympathetic modulation before the TT, and the inclusion of brief sprints resulted in a higher initial power output during the TT. However, no warm-up benefits were found for overall TT performance or for perceptual or physiological responses during the TT.

Social Support Mediates the Effect of Burnout on Health in Health Care Professionals.

Burnout is characterized by emotional exhaustion and caused by exposure to excessive and prolonged stress related to job conditions. Moreover, burnout is highly prevalent among health care professionals. The aim of this study is, first, to examine the mediating role of social support over the effect of burnout in health care professionals and, second, to explore potential gender differences. A convenience sample of 1,035 health professionals from Ecuador, including 608 physicians and 427 nurses (68% women, with and age M = 40 + 9 years old), was surveyed using the Maslach Burnout Inventory (MBI), Social Support Survey (MOS), and General Health Questionnaire (GHQ-28) as measures of burnout, social support, and general health, respectively. Social support was found to mediate the negative effects of burnout on health regardless of gender. Differences across the three dimensions of burnout and health are further discussed, along with their implications for designing effective burnout interventions for health care professionals in Ecuador.

Psychophysiological Patterns Related to Success in a Special Operation Selection Course.

Actual theaters of operations require fast actions from special operations units with a high level of readiness and survival. Mission accomplishment depends on their psychological and physiological performance. The aim of the present study was to analyze: (1) the physical parameters related with success in a special operation selection course; and (2) the modifications of the psychological profile of recruits before and after a special operation selection course. Fifty-five male soldiers of the Spanish Army (25.1 ± 5.0 years, 1.8 ± 0.1 cm, 76.8 ± 7.9 kg, 24.4 ± 2.5 kg/m2) undertaking a 10-week special operation selection course performed a battery of physiological and psychological tests. Results showed how successful soldiers presented higher leg strength, anaerobic running performance, and cardiovascular response than non-successful soldiers. The psychological values of life engagement test, acceptance and action questionnaire, coping flexibility scale, and perceived stress scale did not present significant differences after the selection course. We can conclude that success in a special operation selection course was related to higher anaerobic and cardiovascular fitness. This special operation selection course did not modify the psychological profile of successful soldiers.

Effect of different combat jet manoeuvres in the psychophysiological response of professional pilots.

Extreme limits of the human body could be reached in air combat. We analysed 29 fighter pilots before and after offensive and defensive manoeuvres on heart rate (HR), heart rate variability, leg and hand strength, spirometry, temperature, blood oxygen saturation (BOS), lactate, hydration (USG), cortical activation, memory and psychological variables. The defensive manoeuvre produced a significative decrease in forced vital capacity from spirometry and USG post flight, a moderate effect in the decrease in cognitive anxiety and an increase in leg strength. A significant increase in mean HR and an increase with a large effect size was reported for Stress Subjective Perception and Rating of Perceived Exertion in both manoeuvres. With this data we can conclude that high level of physical fitness and specific training programs should be applied to fighter pilots.