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Christian Collet, Aymeric Guillot, Olivier Bolliet and André Dittmar

Purpose:

To examine the preparation phase for the snatch lift in Olympic weight lifting. Two behavioral periods were studied, each corresponding to specific mental processes: a stance in front of the bar and placement of hands on the bar. Each period was hypothesized to elicit different responses of autonomic-nervous-system activity.

Methods:

Twelve elite male subjects completed 12 lifts at 90% to 95% of their best grade after warm-up (80% of their best grade). Because peripheral autonomic-nervous-system activity is related to arousal and activation variation, 6 variables were continuously recorded: electrodermal (skin resistance and potential), thermovascular (skin temperature and skin blood flow), and cardiorespiratory (heart rate and respiratory frequency).

Results:

Responses (ie, phasic activities) were evident during the fi rst behavioral period. Decrease in heart rate (mean = 19 beats/min) or in respiratory frequency (mean = 8.6 beats/min) was related to attention processes. These responses were weaker (−0.16°C vs −0.25°C in skin temperature) and shorter (2.7 seconds vs 4.3 seconds in skin resistance) than those recorded during execution. The second phase showed variations in basal levels (mean increase in heart rate of 25%), related to increase in activation, thus attesting the muscle system’s process of preparation for effort.

Conclusion:

Weight lifters separated the preparation phase into 2 stages that were closely matched by different physiological activities. Weight lifting requires participants to share their mental resources among the 2 demanding concentration phases by first focusing their attention on the execution and then mobilizing energizing resources.

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Mònica Solana-Tramunt, Jose Morales, Bernat Buscà, Marina Carbonell and Lara Rodríguez-Zamora

-rate variability (HRV) describes the variation in beat-by-beat intervals in different situations. 9 Several studies have used HRV to monitor individual recovery and training adaptations to better understand the status of the autonomic nervous system, stress, and recovery balance in elite athletes. 4 , 10 , 11

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Nicolas Olivier, Renaud Legrand, Jacques Rogez, FX Gamelin, Serge Berthoin and Thierry Weissland

Objective:

To analyze the consequences on heart rate variability (HRV) of a hospitalization period due to surgery of the knee in sportsmen.

Patients:

Ten soccer players who had undergone knee surgery took part in this study.

Design:

HRV was measured before and after hospitalization within a 7-day interval.

Results:

After the hospitalization phase, heart rate at rest increased significantly (3 beats/minute). A significant decrease of 7% in the cardiac inter beat interval (R-R interval), P < 0.05 and a 66% decrease in total power spectral density: −66%, P < 0.05 were observed. The disturbance of the autonomic nervous system could be due to a variation in cardiac vagal activity resulting in a 64% decrease in the high frequencies (P < 0.05). This variation was not associated with a modification in normalized markers (LFn.u., HFn.u.) and LF/HF ratio (P > 0.05).

Conclusion:

In sportsmen, a hospitalization period led to an increase in resting heart rate and was associated with a disturbance of the autonomic nervous system.

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Kaisu Marjut Kaikkonen, Raija irmeli Korpelainen, Mikko P. Tulppo, Hannu Sakari Kaikkonen, Marja Liisa Vanhala, Mika Antero Kallio, Sirkka M. Keinänen-Kiukaanniemi and Juha Tapani Korpelainen

Background:

Autonomic nervous system (ANS) dysfunction and obesity are intrinsically related to each other. In normal-weight subjects physical activity (PA) and fitness are related to cardiovascular autonomic regulation, providing evidence that aerobic training may improve ANS functioning measured by heart rate variability (HRV). The goal of this study was to investigate the association between lifetime PA, aerobic fitness and HRV in obese adults.

Methods:

Participants included 107 (87 females) volunteers (mean age 44.5 years, median BMI 35.7) who completed health and lifestyle questionnaires and measurements of maximal aerobic performance, anthropometry and 24 h HRV.

Results:

In the multivariate linear regression analyses, lifetime physical activity explained 40% of the variance in normal R-R intervals (SDNN). Each 1-category increase in the activity index increased SDNN by 15.4 (P = .009) and 24% of the variance in natural logarithmic value of ultra-low frequency power (P = .050). High measured VO2max explained 45% of the variance in natural logarithmic value of high-frequency power (P = .009) and 25% of the variance in low frequency/high frequency ratio (P < .001).

Conclusions:

Lifetime physical activity and aerobic fitness may reduce obesity-related health risks by improving the cardiac autonomic function measured by HRV in obese workingage subjects. This research supports the role of lifetime physical activity in weight management strategies and interventions to reduce obesity-related health risks.

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Carla Cristiane da Silva, Ligia Maxwell Pereira, Jefferson Rosa Cardoso, Jonathan Patrick Moore and Fábio Yuzo Nakamura

The positive effects of physical training on heart rate variability (HRV) in healthy adults are widely recognized; however, the responsiveness to training in healthy children has not yet been established. The aim of this study was to determine the influence of physical training on HRV in prepubertal healthy children. Systematic computerized searches were performed from 1950 to 2012 in the following databases: Medline, Embase, Cinahl, Lilacs, Scielo, SportDiscus, ProQuest; Web of Science; PEDro; Academic Search Premier and the Cochrane Library. The key words used were: heart rate variability, autonomic nervous system, exercise training, physical activity, continuous exercise, intermittent exercise, children, prepubescent, adolescents, and healthy. Although the database search initially identified 6,164 studies, after removing duplicates and excluding by title the number was 148, however, only 2 studies were included in this systematic review. The meta-analysis compared the experimental group (n = 29) with the control group (n = 28) for the HRV parameters: RR intervals, SDNN, RMSSD, pNN50, LF (log), HF (log), LF/HF and Total Power (log). The meta-analysis demonstrated similar HRV indices between both the experimental and control groups. In conclusion, the available results from randomized controlled trials do not support the hypothesis that physical training improves HRV in healthy children[AUQ2].

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Júlio A. Costa, João Brito, Fábio Y. Nakamura, Eduardo M. Oliveira, Ovidio P. Costa and António N. Rebelo

bright polychromatic light (≥1000 lux) being sufficient to elicit maximal alerting effects during sleep. 38 Overnight HRV has been attracting great interest in the assessment of the autonomic nervous system activity and recovery from daily load, due to its noninvasive nature. 6 Nighttime is generally

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Anna Valenzano, Fiorenzo Moscatelli, Antonio Ivano Triggiani, Laura Capranica, Giulia De Ioannon, Maria Francesca Piacentini, Sergio Mignardi, Giovanni Messina, Stefano Villani and Giuseppe Cibelli

Purpose:

To evaluate the effect of a solo ultraendurance open-water swim on autonomic and nonautonomic control of heart rate (HR).

Methods:

A male athlete (age 48 y, height 172 cm, body mass 68 kg, BMI 23 kg/m2) underwent HR-variability (HRV) and circulating catecholamine evaluations at different times before and after an ultraendurance swim crossing the Adriatic Sea from Italy to Albania. HRV was measured in 5-min segments and quantified by time and frequency domain. Circulating catecholamines were estimated by salivary alpha-amylase (sAA) assay.

Results:

The athlete completed 78.1 km in 23:44 h:min. After arrival, sAA levels had increased by 102.6%. Time- and frequency-domain HRV indexes decreased, as well (mean RR interval, −29,7%; standard deviation of normal mean RR interval, −63,1%; square root of mean squared successive differences between normal-to-normal RR intervals, −49.3%; total power, −74.3%; low frequency, −78.0%; high frequency, −76.4%), while HR increased by 41.8%. At 16-h recovery, sAA had returned to preevent values, while a stable tachycardia was accompanied by reduced HRV measures.

Conclusion:

To the authors’ knowledge, this is the first study reporting cardiac autonomic adjustments to an extreme and challenging ultraendurance open-water swim. The findings confirmed that the autonomic drives depend on exercise efforts. Since HRV changes did not mirror the catecholamine response 16 h postevent, the authors assume that the ultraendurance swim differently influenced cardiac function by both adaptive autonomic and nonautonomic patterns.

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Clint R. Bellenger, Laura Karavirta, Rebecca L. Thomson, Eileen Y. Robertson, Kade Davison and Jonathan D. Buckley

Purpose:

Heart-rate variability (HRV) as a measure of autonomic function may increase in response to training interventions leading to increases or decreases in performance, making HRV interpretation difficult in isolation. This study aimed to contextualize changes in HRV with subjective measures of training tolerance.

Methods:

Supine and standing measures of vagally mediated HRV (root-mean-square difference of successive normal RR intervals [RMSSD]) and measures of training tolerance (Daily Analysis of Life Demands for Athletes questionnaire, perception of energy levels, fatigue, and muscle soreness) were recorded daily during 1 wk of light training (LT), 2 wk of heavy training (HT), and 10 d of tapering (T) in 15 male runners/triathletes. HRV and training tolerance were analyzed as rolling 7-d averages at LT, HT, and T. Performance was assessed after LT, HT, and T with a 5-km treadmill time trial (5TTT).

Results:

Time to complete the 5TTT likely increased after HT (effect size [ES] ± 90% confidence interval = 0.16 ± 0.06) and then almost certainly decreased after T (ES = −0.34 ± 0.08). Training tolerance worsened after HT (ES ≥ 1.30 ± 0.41) and improved after T (ES ≥ 1.27 ± 0.49). Standing RMSSD very likely increased after HT (ES = 0.62 ± 0.26) and likely remained higher than LT at the completion of T (ES = 0.38 ± 0.21). Changes in supine RMSSD were possible or likely trivial.

Conclusion:

Vagally mediated HRV during standing increased in response to functional overreaching (indicating potential parasympathetic hyperactivity) and also to improvements in performance. Thus, additional measures such as training tolerance are required to interpret changes in vagally mediated HRV.

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Lucas C. Bianco, James M. May, Smokey L. Fermin, Robert Oates and Scott W. Cheatham

In the current case series, three male patients aged 19–21 years, all participating in basketball activities during their competitive season, were evaluated and classified with patella tendinopathy. A combination of positional release therapy (PRT) treatment with therapeutic exercises was used to decrease pain and improve function. Over the course of the treatment, each patient improved outcomes at discharge and sustained the improvements at follow-up. The purpose of this paper is to compare the results of this case series with a study of the effects of eccentric exercises on physically active patients diagnosed with patella tendinopathy and participating in jumping sports.

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Carla Cristiane Silva, Maurizio Bertollo, Felipe Fossati Reichert, Daniel Alexandre Boullosa and Fábio Yuzo Nakamura

Purpose:

To examine which body position and indices present better reliability of heart rate variability (HRV) measures in children and to compare the HRV analyzed in different body positions between sexes.

Method:

Twenty eutrophic prepubertal children of each sex participated in the study. The RR intervals were recorded using a portable heart rate monitor twice a day for 7 min in the supine, sitting, and standing positions. The reproducibility was analyzed using the intraclass correlation coefficient (ICC; two way mixed) and within-subject coefficient of variation (CV).Two-way ANOVA with repeated measures was used to compare the sexes.

Results:

High levels of reproducibility were indicated by higher ICC in the root-mean-square difference of successive normal RR intervals (RMSSD: 0.93 and 0.94) and Poincaré plot of the short-term RR interval variability (SD1: 0.92 and 0.94) parameters for boys and girls, respectively, in the supine position. The ICCs were lower in the sitting and standing positions for all HRV indices. In addition, the girls presented significantly higher values than the boys for SDNN and absolute high frequency (HF; p < .05) in the supine position.

Conclusions:

The supine position is the most reproducible for the HRV indices in both sexes, especially the vagal related indices.