scholarly journals Positive Relationship Between Precompetitive Sympathetic Predominance and Competitive Performance in Elite Extreme Sports Athletes

2021 ◽  
Vol 3 ◽  
Author(s):  
Seiji Matsumura ◽  
Ken Watanabe ◽  
Naoki Saijo ◽  
Yuuki Ooishi ◽  
Toshitaka Kimura ◽  
...  
Keyword(s):  
Heart Rate ◽  
Sympathetic Tone ◽  
Superior Performance ◽  
High Frequency Component ◽  
Component Ratio ◽  
Competitive Performance ◽  
Extreme Sports ◽  
The Mean ◽  
And Performance ◽  
The Relationship

Elite athletes achieve superior performance under high pressure in competitive situations. Although it is known that such situations affect the precompetitive activity of their autonomic nervous system (ANS), the relationship between precompetitive ANS activity and performance remains controversial. Especially in extreme sports, it has been shown that cardiac sympathetic tone occurs in athletes before competition attempts. However, the relationship between precompetitive sympathetic tone and performance is unclear. To investigate this relationship in extreme sports, we organized a freestyle snowboard jumping competition and examined competitors' physiological states and performance during this event. The electrocardiograms (ECGs) of 20 elite snowboarders were measured 10 min before each jump in different competitive situations: practice, qualifying, and final sessions. The mean heart rate (HR), the low-frequency to high-frequency component ratio (LF/HF ratio), the logarithm of the HF (lnHF) component of the frequency-domain of the heart rate variability (HRV), the ratio of the standard deviation of all R–R intervals to the root mean square of successive differences of R–R intervals (SDNN/rMSSD ratio), and the rMSSD of the time-domain of the HRV were calculated from the ECG data. The results showed a significant increase in the mean HR as well as significant decreases in the lnHF component and rMSSD of the HRV as the sessions progressed. Interestingly, the mean HR, LF/HF ratio and SDNN/rMSSD ratio of the HRV showed significant positive correlations with competitive scores, and the lnHF component and rMSSD of the HRV showed significant negative correlations with the scores. Our results indicate that precompetitive ANS activity becomes predominantly sympathetic in elite extreme athletes, such as freestyle snowboarders, when the competition intensifies, and that this sympathetic predominance is positively related to competitive performance.

scholarly journals Indices of Heart Rate Variability and Performance During a Response-Conflict Task Are Differently Associated With ADHD and Autism

2021 ◽  
pp. 108705472097279
Author(s):  
Alessio Bellato ◽  
Iti Arora ◽  
Puja Kochhar ◽  
Chris Hollis ◽  
Madeleine J. Groom
Keyword(s):  
Heart Rate ◽  
Heart Rate Variability ◽  
Sensory Information ◽  
Response Conflict ◽  
Mediation Model ◽  
Conflict Task ◽  
Accurate Performance ◽  
And Performance ◽  
Comorbid Adhd ◽  
The Relationship

We investigated autonomic arousal, attention and response conflict, in ADHD and autism. Heart rate variability (HRV), and behavioral/electrophysiological indices of performance, were recorded during a task with low and high levels of response conflict in 78 children/adolescents (7–15 years old) with ADHD, autism, comorbid ADHD+autism, or neurotypical. ANOVA models were used to investigate effects of ADHD and autism, while a mediation model was tested to clarify the relationship between ADHD and slower performance. Slower and less accurate performance characterized ADHD and autism; however, atypical electrophysiological indices differently characterized these conditions. The relationship between ADHD and slower task performance was mediated by reduced HRV in response to the cue stimulus. Autonomic hypo-arousal and difficulties in mobilizing energetic resources in response to sensory information (associated with ADHD), and atypical electrophysiological indices of information processing (associated with autism), might negatively affect cognitive performance in those with ADHD+autism.

Heart Rate and Neurological Outcomes in Patients Undergoing Targeted Temperature Management

2020 ◽  
pp. 088506662098250
Author(s):  
Chad M. Conner ◽  
William H. Perucki ◽  
Andre Gabriel ◽  
David M. O’Sullivan ◽  
Antonio B. Fernandez
Keyword(s):  
Heart Rate ◽  
Positive Association ◽  
Targeted Temperature Management ◽  
Temperature Management ◽  
Neurological Outcomes ◽  
Neurologic Outcomes ◽  
Resuscitation Guidelines ◽  
The Mean ◽  
The Impact ◽  
The Relationship

Introduction: There is a paucity of data evaluating the impact of heart rate (HR) during Targeted Temperature Management (TTM) and neurologic outcomes. Current resuscitation guidelines do not specify a HR goal during TTM. We sought to determine the relationship between HR and neurologic outcomes in a single-center registry dataset. Methods: We retrospectively studied 432 consecutive patients who completed TTM (33°C) after cardiac arrest from 2008 to 2017. We evaluated the relationship between neurologic outcomes and HR during TTM. Pittsburgh Cerebral Performance Categories (CPC) at discharge were used to determine neurological recovery. Statistical analysis included chi square, Student’s t-test and Mann-Whitney U. A logistic regression model was created to evaluate the strength of contribution of selected variables on the outcome of interest. Results: Approximately 94,000 HR data points from 432 patients were retrospectively analyzed; the mean HR was 82.17 bpm over the duration of TTM. Favorable neurological outcomes were seen in 160 (37%) patients. The mean HR in the patients with a favorable outcome was lower than the mean HR of those with an unfavorable outcome (79.98 bpm vs 85.67 bpm p < 0.001). Patients with an average HR of 60-91 bpm were 2.4 times more likely to have a favorable neurological outcome compared to than HR’s < 60 or > 91 (odds ratio [OR] = 2.36, 95% confidence interval [CI] 1.61-3.46, p < 0.001). Specifically, mean HR’s in the 73-82 bpm range had the greatest rate of favorable outcomes (OR 3.56, 95% CI 1.95-6.50), p < 0.001. Administration of epinephrine, a history of diabetes mellitus and hypertension all were associated with worse neurological outcomes independent of HR. Conclusion: During TTM, mean HRs between 60-91 showed a positive association with favorable outcomes. It is unclear whether a specific HR should be targeted during TTM or if heart rates between 60-91 bpm might be a sign of less neurological damage.

Fitness Load and Exercise Time in Secondary Physical Education Classes

1993 ◽  
Vol 12 (2) ◽  
pp. 180-187 ◽  
Author(s):  
Xiao Jun Li ◽  
Paul Dunham
Keyword(s):  
Heart Rate ◽  
Physical Education ◽  
Student Behavior ◽  
Skill Level ◽  
Exercise Time ◽  
Record Heart Rate ◽  
Classified Students ◽  
The Mean ◽  
Relationship Of ◽  
The Relationship

This study investigated the effect of secondary school physical education on fitness load. Fitness load was defined as the product of the mean heart rate above threshold (144 bpm) and fitness time (the duration of the heart rate above threshold). The relationship of fitness load and skill level of students was also studied. Teachers of 24 classes classified students as having high, moderate, or low skill ability. Seventy-two students, 1 from each skill level in each class, wore heartwatches to record heart rate at 15-s intervals. Student behavior was videotaped and coded. Twenty-one percent of the classes produced an overload effect, and 79% did not. The highly and moderately skilled students achieved fitness load more frequently than their lower skilled colleagues. The relationship between fitness load and percentage of time exercising was r = .66, indicating 44% common variance.

scholarly journals Does social responsibility matter for firm performance? Evidence from Brazil

2012 ◽  
Vol 9 (3) ◽  
pp. 132-141 ◽  
Author(s):  
Thiago Emmanuel ◽  
Andre Carvalhal da Silva ◽  
Marcos Avila
Keyword(s):  
Firm Performance ◽  
Social Responsibility ◽  
Financial Performance ◽  
Firm Value ◽  
Superior Performance ◽  
Social Report ◽  
Points Of View ◽  
And Performance ◽  
The Relationship ◽  
Over Time

This paper analyses the relationship between social responsibility and financial performance of Brazilian companies. This subject has been largely studied and presents many discussions and different points of view. There are a considerably number of research that tries to link social responsibility and financial performance. However, there is not a fully established consensus about the issue. Despite a great number of empirical researches regarding this subject, there are few studies in the Brazilian market. We analyze 515 Brazilian companies listed on BM&FBovespa from 2001 to 2007 and check which companies have disclosed the IBASE social report, which proposes a standardized methodology for social reporting and allows us to compare companies in different sectors over time. Our results indicate that companies that disclose social information have a superior performance when compared with companies that do not disclose. Moreover, financial performance is positively related with social investments. Interestingly, the "voluntary" social investments, which are not mandatory by law, have a strong effect on firm value and performance.

scholarly journals Impact of Leadership on the Relationship Between Innovation and Performance

2021 ◽  
Vol 5 (2) ◽  
pp. 29-49
Author(s):  
Cláudia Ferreira Leitão ◽  
Jorge Gomes ◽  
Denise Capela dos Santos ◽  
Bruno Melo Maia
Keyword(s):  
Middle Managers ◽  
Hotel Industry ◽  
Moderating Effect ◽  
Superior Performance ◽  
Organizational Success ◽  
Positive Correlation ◽  
Hotel Sector ◽  
And Performance ◽  
The Impact ◽  
The Relationship

Leadership, innovation, and performance are essential factors to achieve the desired sustainable profitability of companies. The relationship between these variables is one of the keys to the organizational success, although their study has proved to be complex. The purpose of this article is to analyse the impact of leadership on the relationship between innovation and performance in the Portuguese hotel sector. To answer to this challenge, a survey was carried out to top and middle managers of four-star and five-star hotel units. The existence of a positive correlation between innovation and performance was found; however, leadership has not been shown to have a moderating effect on the relationship. The work highlights several important contributions to the hotel industry and identifies aspects that, when well implemented and developed, can lead to superior performance in organizations.

Multinationality and performance effects: an integrated theory of new patterns of multinationality and home political influence

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
I-Fan Yen ◽  
Hsin-Mei Lin
Keyword(s):  
Multinational Enterprises ◽  
Positive Relationship ◽  
Political Influence ◽  
Superior Performance ◽  
Foreign Investments ◽  
Content Type ◽  
Performance Effect ◽  
Performance Effects ◽  
And Performance ◽  
The Relationship

Purpose This paper aims to develop an integrated perspective on the relationship between multinationality and performance in the outward foreign direct investment (OFDI) of Chinese firms. The study not only represents contrasting OFDI patterns – namely, born global-natured multiple synchronous foreign investments versus conventional internationalization process (IP)-natured steady increasing foreign investments – but also contributes to understanding the extent to which explanations of home political influence need to be rooted within the general theory of multinationality. Design/methodology/approach By testing a comprehensive panel observation of 8,635 OFDI projects from 1991-2016 in China, this study found that multinationality with the new pattern of multiple synchronous OFDIs has a superior performance effect compared with the conventional pattern of steady increasing OFDIs. Findings This study also finds a positive relationship between multinationality (international diversification and home political influence) and the performance effect with the new pattern of multiple synchronous OFDIs, as well as a partial positive relationship between multinationality and the performance effect with the conventional pattern of steady increasing OFDIs. Research limitations/implications The study extends the understanding of the performance effects of Chinese multinational enterprises, which may benefit more from the new pattern of multiple synchronous OFDIs than from the conventional pattern of steady increasing OFDIs when the home-country institution is strongly positioned. Originality/value This paper concludes that multinationality needs an integrated framework that accounts for the new pattern of OFDI and the influence of diversification and home politics, particularly for the emerging country, China.

The relationship between heat flow and vasculature in the dorsal fin of wild bottlenose dolphinsTursiops truncatus

2002 ◽  
Vol 205 (22) ◽  
pp. 3475-3486 ◽  
Author(s):  
Erin M. Meagher ◽  
William A. McLellan ◽  
Andrew J. Westgate ◽  
Randall S. Wells ◽  
Dargan Frierson ◽  
...  
Keyword(s):  
Heart Rate ◽  
Heat Flux ◽  
Bottlenose Dolphins ◽  
Dorsal Fin ◽  
Respiratory Event ◽  
Vascular Structures ◽  
The Mean ◽  
Body Cooling ◽  
The Relationship ◽  
Body Heat

SUMMARYThe dorsal fin of the bottlenose dolphin Tursiops truncatuscontains blood vessels that function either to conserve or to dissipate body heat. Prior studies have demonstrated that heat flux, measured from a single position on the dorsal fin, decreases during body cooling and diving bradycardia and increases after exercise and at the termination of the dive response. While prior studies attributed changes in heat flux to changes in the pattern of blood flow, none directly investigated the influence of vascular structures on heat flux across the dorsal fin. In this study we examined whether heat flux is higher directly over a superficial vein,compared to a position away from a vein, and investigated the temporal relationship between heart rate, respiration and heat flux. Simultaneous records of heat flux and skin temperature at three positions on the dorsal fins of 19 wild bottlenose dolphins (with the fin in air and submerged) were collected, together with heart rate and respiration. When the fin was submerged, heat flux values were highest over superficial veins, usually at the distal tip, suggesting convective delivery of heat, via blood, to the skin's surface. Conversely, in air there was no relationship between heat flux and superficial vasculature. The mean difference in heat flux (48 W m-2) measured between the three fin positions was often equal to or greater than the heat flux that had been recorded from a single position after exercising and diving in prior studies. Tachycardia at a respiratory event was not temporally related to an increase in heat flux across the dorsal fin. This study suggests that the dorsal fin is a spatially heterogeneous thermal surface and that patterns of heat flux are strongly influenced by underlying vasculature.

scholarly journals Physiological Response of Quality Cardiopulmonary Resuscitation, Crossover Trial on Mannequin in Extreme Temperature Conditions

2020 ◽  
Vol 17 (16) ◽  
pp. 5835 ◽  
Author(s):  
José Luis Martin-Conty ◽  
Begoña Polonio-López ◽  
Clara Maestre-Miquel ◽  
Alicia Mohedano-Moriano ◽  
Carlos Durantez-Fernández ◽  
...  
Keyword(s):  
Heart Rate ◽  
Cardiopulmonary Resuscitation ◽  
Extreme Temperature ◽  
Physiological Parameters ◽  
Thermal Environments ◽  
Cpr Quality ◽  
Total Proportion ◽  
The Mean ◽  
The Relationship

Background: To determine the relationship between physiological fatigue and the quality of cardiopulmonary resuscitation (CPR) in trained resuscitators in hostile thermal environments (extreme cold and heat) simulating the different conditions found in an out-of-hospital cardiorespiratory arrest. Methods: Prospective observational study involving 60 students of the health sciences with training in resuscitation, who simulated CPR on a mannequin for 10 min in different thermal environments: thermo-neutral environment (21 °C and 60% humidity), heat environment (41 °C and 98% humidity) and cold environment (−35 °C and 80% humidity). Physiological parameters (heart rate and lactic acid) and CPR quality were monitored. Results: We detected a significant increase in the number of compressions per minute in the “heat environment” group after three minutes and in the mean rate after one minute. We observed a negative correlation between the total number of compressions and mean rate with respect to mean depth. The fraction of compressions (proportion of time in which chest compressions are carried out) was significant over time and the mean rate was higher in the “heat environment”. Physiological parameters revealed no differences in heart rate depending on the resuscitation scenario; however, there was a greater and faster increase in lactate in the “heat environment” (significant at minute 3). The total proportion of participants reaching metabolic fatigue was also higher in the “heat environment”. Conclusions: A warm climate modifies metabolic parameters, reducing the quality of the CPR maneuver.

scholarly journals The Relationship Between Intensity Indicators in Small-Sided Soccer Games

2015 ◽  
Vol 46 (1) ◽  
pp. 119-128 ◽  
Author(s):  
David Casamichana ◽  
Julen Castellano
Keyword(s):  
Heart Rate ◽  
External Load ◽  
Perceived Exertion ◽  
Internal Load ◽  
Heart Rate Monitors ◽  
The Mean ◽  
Gps Devices ◽  
The Individual ◽  
The Relationship ◽  
Mean Heart Rate

AbstractThe aim of the present study was to examine the relationship between different kinds of intensity indicators in small-sided soccer games. This descriptive correlational study included 14 semi-professional male soccer players (21.3 ± 2.3 years, 174 ± 4.0 cm, 73.4 ± 5.1 kg) from the same team. The players were monitored by means of heart rate monitors and GPS devices during 27 small-sided games of nine different formats, yielding a total of 217 recordings. After each game the Borg scale was used to give a rate of perceived exertion (RPE). The internal load indicators were the mean heart rate relative to the individual maximum (%HRmean) and the RPE, while those for the external load were the player load, total distance covered, distance covered in two intensity ranges (>18 km·h-1 and >21 km·h-1), and frequency of effort (in the same two intensity ranges). There was a significant moderate correlation (r=0.506) between the two internal load measurements (%HRmean and RPE). Although there were significant correlations of different degrees between various external load measurements, only the player load was significantly correlated with the internal load indicators (r=0.331 with %HRmean and r=0.218 with RPE). During training programes of this kind, it is necessary to consider a range of intensity indicators so as to obtain complementary information. This will enable coaches to more accurately assess the load imposed on players and therefore optimize the training process.

scholarly journals La variabilidad de la frecuencia cardiaca en el control del entrenamiento en un corredor de Ironman. Estudio de caso (Heart Rate Varibility in the training monitoring of an Ironman runner. A case study)

Retos ◽  
2019 ◽  
pp. 339-343
Author(s):  
Claudio Nieto-Jimenez ◽  
José Ruso-Álvarez ◽  
Elena Elena Pardos-Mainer ◽  
José Naranjo Orellana
Keyword(s):  
Heart Rate ◽  
Sympathetic Activity ◽  
Training Load ◽  
Moderate Increase ◽  
Load Planning ◽  
Training Methodology ◽  
The Mean ◽  
Stress Score ◽  
The Relationship

El objetivo de este artículo es el de proporcionar información sobre la carga de entrenamiento a partir del seguimiento de un atleta durante siete meses de preparación para una competición de Ironman (3.8 km de natación, 180 km de ciclismo y 42.195 km de carrera), utilizando una metodología de entrenamiento con registros diarios de variabilidad de la frecuencia cardiaca (VFC). Como variable para evaluar la actividad parasimpática se calculó la raíz cuadrada de la media de las diferencias de la suma de los cuadrados entre intervalos RR adyacentes (RMSSD) y el índice de estrés (SS) como indicador de actividad simpática. En los meses dos, tres y cuatro presentó un moderado incremento del SS (d =1,17) paralelamente a una moderada disminución de la RMSSD (d = -1,04). Para los meses cinco, seis, y siete se observó una pequeña disminución del SS (d = -0,23) y moderado aumento de la RMSSD (d = 1,08). Como concusión es que las mediciones de VFC de cinco minutos al despertar parecen ser una forma útil de monitorizar el estado de equilibrio parasimpático en un triatleta antes de abordar las sesiones de entrenamiento. El análisis de esta monitorización serviría para detectar precozmente posibles estados de fatiga y para poder modificar, en caso necesario, la planificación de las cargas de entrenamiento en la preparación para una competición de Ironman.  Summary. The objective of this article is to provide information on the relationship between external (TL) and internal training load (ITL) from the tracking of an athlete during seven months of preparation for an Ironman competition (3.8 km of swimming, 180 km of cycling, and 42,195 km of running), using a training methodology with daily records of the heart rate variability (HRV). As a variable to assess parasympathetic activity, the square root of the mean of the differences in the sum of the squares between adjacent RR intervals (RMSSD) was calculated, together with the stress score (SS) as an indicator of sympathetic activity. In months two, three and four, there was a moderate increase in SS (d = 1.17) parallel to a moderate decrease in RMSSD (d = -1.04). In months five, six, and seven, a small decrease in SS (d = -0.23) and a moderate increase in RMSSD (d = 1.08) were observed. As a conclusion, the five-minute HRV measurements upon awakening appear to be a useful tool to monitor the state of parasympathetic equilibrium in a triathlete before approaching training sessions. The analysis of this monitoring would serve to detect possible fatigue states in the early stages and to modify, if necessary, the training load planning in preparation for an Ironman competition.

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