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José Naranjo Orellana, Blanca de la Cruz Torres, Elena Sarabia Cachadiña, Moisés de Hoyo and Sergio Domínguez Cobo

Purpose:

The application of Poincaré-plot analysis to heart-rate variability (HRV) is a common method for the assessment of autonomic balance. However, results obtained from the indexes provided by this analysis tend to be difficult to interpret. In this study the authors aimed to prove the usefulness of 2 new indexes: the stress score (SS) and the sympathetic:parasympathetic ratio (S:PS ratio).

Methods:

25 professional Spanish soccer players from same team underwent 330 resting measurements of HRV. All subjects experienced 10 min of HRV monitoring through an R-R-interval recorder. The following parameters were calculated: (1) Poincaré-plot indexes: SD1 (transverse axis), which is proportional to parasympathetic activity; SD2 (longitudinal axis), which is inversely proportional to sympathetic activity; and the SD1:SD2 ratio; (2) time-domain parameters: standard deviation of R-R intervals (SDNN), root-mean-square differences of successive heartbeat intervals (rMSSD), and percentage of successive R-R-interval pairs differing in more than 50 ms in the entire recording divided by the total number of R-R intervals (pNN50); and (3) the proposed 2 new indexes: the SS and the S:PS ratio.

Results:

The study found a high negative correlation between the SS and SDNN (R 2 = .94). The S:PS ratio correlated inversely to rMSSD (R 2 = .95), SDNN (R 2 = .94), and pNN50 (R 2 = .74). The S:PS ratio showed a strong correlation with SD1 (R 2 = .95) and SS (r = .87, R 2 = .88).

Conclusions:

The application of the SS as sympathetic-activity index and the S:PS ratio as a representation of autonomic balance (SS:SD1) provides a better understanding of the Poincaré-plot method in HRV.

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Franciele Marques Vanderlei, Isadora Lessa Moreno, Luiz Carlos Marques Vanderlei, Carlos Marcelo Pastre, Luiz Carlos de Abreu and Celso Ferreira

Despite the importance of hydration during exercise, the impact of ingesting water or isotonic solution during and after exercise on the regulation of autonomic modulation is unclear. The study aimed to compare the effect of ingesting water or isotonic solution (Gatorade®, Brazil) on cardiac autonomic modulation in young people after submaximal aerobic exercise. Thirty-one young men were subjected to a protocol consisting of 4 steps: 1) incremental test, 2) control protocol without hydration, 3) protocol with ingestion of water, and 4) protocol with ingestion of isotonic solution. The protocol consisted of 10 min of rest, 90 min of treadmill exercise at 60% VO2peak, and 60 min of recovery at rest. In the hydration protocols, hydration occurred during and after exercise, every 15 min beginning after the 15th minute of exercise, with the amount ingested proportional to body mass lost in the control protocol. Autonomic modulation was evaluated by heart rate variability. The hydration protocols promoted a more efficient recovery of autonomic modulation, and for the exercise performed, regardless of the hydration administered, the effect on autonomic modulation was similar.

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Hélène Perrault, Maria Tzovanis, Dominique Johnson, André Davignon, Claude Chartrand, Abdelkader Mokrane and Réginald A. Nadeau

This study compares the autonomic responses of 9 adolescents (mean ± SEM: 17±1 years) successfully operated for tetralogy of Fallot (TOF) in early childhood and 8 age-matched healthy controls (CTRL) using R-R and blood pressure variability. Continuous ECG and BP recordings were obtained during spontaneous and controlled respiration (CR) at 0.20 Hz as well as after an 85° head-up tilt (HUT) and during steady-state cycling at heart rates of 100 and 120 bpm, selected to reflect partial and complete cardiac vagal withdrawal. TOF exhibited total R-R variance and HF power (ms2) lower than CTRL under both spontaneous (938 ± 322 vs. 1,714 ± 296) and CR (1,541 ± 527 vs. 4,725 ± 1,207; p < .05), which may be indicative of a lower cardiac vagal activity. HUT decreased the R-R HF component, which remained lower in TOF than CTRL and increased the diastolic BP LF component in TOF but not in CTRL. Exercise decreased the R-R HF power more in TOF than CTRL. The exaggerated diastolic BP and limited heart rate responses to tilting and the more marked vagal withdrawal at Ex120 in TOF may be suggestive of a disturbance in the cardiac sympathetic response. Further studies are needed to confirm these observations on larger groups of young adults successfully operated for TOF.

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Paulo Farinatti, Silvio Rodrigues Marques Neto, Ingrid Dias, Felipe A. Cunha, Eliete Bouskela and Luiz G. Kraemer-Aguiar

Purpose:

Cardiac autonomic dysfunction (CADysf) in children is often associated to obesity and may be attenuated by physical activity. In this study, we investigated the effects of resistance training (RT) upon CADysf assessed by heart rate variability (HRV) in obese adolescents.

Method:

Volunteers were assigned into groups according to standard deviation scores for body mass index (z-BMI) and percentile for age and sex: obese (OB; z-BMI from 2 to 3 and ≥ 95th percentile, n = 24) and normal weight controls (CG; z-BMI from -2–1 and < 85th percentile, n = 20). OB performed isolated RT during 12 weeks [3 sets of 6–10reps with 70–85% 10RM]. Waist circumference, systolic/diastolic blood pressures (SBP/DBP), lipids, and HRV were assessed at baseline. Only OB underwent postintervention assessments.

Results:

At baseline, SBP (122.4 ± 9.1 vs. 109.7 ± 11.5 mmHg, p < .001) and DBP (76.1 ± 7.1 vs. 65.3 ± 5.9 mmHg, p < .001) were higher, while parasympathetic HRV indexes were lower (p < .05) in OB compared with CG. After RT, waist circumference (3%, p < .001) and SBP (10%, p < .001) reduced in OB. Parasympathetic indexes of HRV increased in OB (SDNN: 25%, p = .03; rMSSD: 48%, p = .0006; pNN50: 67%, p = .001; total power: 54%, p = .01; HF: 101%, p = .001) and baseline differences between groups for sympathetic and parasympathetic activities were no longer observed after RT.

Conclusion:

RT attenuated CAdyfs and BP in obese adolescents, by increasing parasympathetic activity and decreasing sympatho-vagal balance.

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Stewart A. Vella and Dana J. Perlman

The purpose of this paper is to provide a concise resource for coaches, coach educators, and coaching scientists by reviewing three common approaches to coaching: the mastery approach to coaching; autonomy-supportive coaching; and the transformational leadership approach to coaching. The theoretical foundations, purpose, evidence base, specifed behaviours, and translation into coaching and coach education of each approach are reviewed. Despite diverse theoretical foundations and variations in purpose, there is some overlap in the coaching behaviours prescribed by each approach. However, there is limited empirical evidence to support the use of the three approaches in coach education and this is detrimental to effective and evidence-based coach education. Efforts to integrate theoretical foundations are promising, and a comprehensive prescription of coaching behaviours based on an integration of the three approaches is possible. This approach can potentially lead to cumulative effects on positive athlete outcomes. Future research should elucidate the common and unique contributions of these approaches to athletes’ outcomes, and whether they differ by age, sex, type of sport, or competition level.

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Hélcio Kanegusuku, Andréia C.C. Queiroz, Valdo J.D. Silva, Marco T. de Mello, Carlos Ugrinowitsch and Cláudia L.M. Forjaz

The effects of high-intensity progressive resistance training (HIPRT) on cardiovascular function and autonomic neural regulation in older adults are unclear. To investigate this issue, 25 older adults were randomly divided into two groups: control (CON, N = 13, 63 ± 4 years; no training) and HIPRT (N = 12, 64 ± 4 years; 2 sessions/week, 7 exercises, 2−4 sets, 10−4 RM). Before and after four months, maximal strength, quadriceps cross-sectional area (QCSA), clinic and ambulatory blood pressures (BP), systemic hemodynamics, and cardiovascular autonomic modulation were measured. Maximal strength and QCSA increased in the HIPRT group and did not change in the CON group. Clinic and ambulatory BP, cardiac output, systemic vascular resistance, stroke volume, heart rate, and cardiac sympathovagal balance did not change in the HIPRT group or the CON group. In conclusion, HIPRT was effective at increasing muscle mass and strength without promoting changes in cardiovascular function or autonomic neural regulation.

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Athanasios Mouratidis, Willy Lens and Maarten Vansteenkiste

We relied on self-determination theory (SDT; Deci & Ryan, 2000) to investigate to what extent autonomy-supporting corrective feedback (i.e., feedback that coaches communicate to their athletes after poor performance or mistakes) is associated with athletes’ optimal motivation and well-being. To test this hypothesis, we conducted a cross-sectional study with 337 (67.1% males) Greek adolescent athletes (age M = 15.59, SD = 2.37) from various sports. Aligned with SDT, we found through path analysis that an autonomy-supporting versus controlling communication style was positively related to future intentions to persist and well-being and negatively related to ill-being. These relations were partially mediated by the perceived legitimacy of the corrective feedback (i.e., the degree of acceptance of corrective feedback), and, in turn, by intrinsic motivation, identified regulation, and external regulation for doing sports. Results indicate that autonomy-supporting feedback can be still motivating even in cases in which such feedback conveys messages of still too low competence.

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Danae Dinkel, Jennifer Huberty, Melissa Tibbits and Melicia Whitt-Glover

Girls are less active than boys and in need of physical activity (PA) interventions. The time directly following school may be a prime opportunity to increase PA, specifically in girls. Afterschool programs and the staff who serve as role models play a critical role in promoting girls’ PA. However, staff do not always provide the support necessary to encourage girls to be active. Studies are needed to explore afterschool program staff’s perceptions of girls’ motivation, as well as their provision of support for autonomy, competence, and relationships with girls (relatedness) to understand how to best promote PA. The purpose of this study was to explore staff and girls’ perceptions of girls’ motivation for PA. The secondary purpose was to explore staff and girls’ perceptions of autonomy, competence, and relatedness support for PA. Interviews with staff (n = 45) and focus groups with girls (n = 88) occurred in 10 afterschool program sites. Half of staff compared with a majority of girls thought girls’ motivation was intrinsic and self-determined (e.g., participated for enjoyment). Three-fourths of staff reported attempting to gain girls’ input and a majority of girls felt they had autonomy to choose or input on the PA provided. Half of staff compared with a quarter of girls thought girls’ competence was negatively impacted by other children. Finally, staff and girls reported spending time together in sedentary pursuits. Efforts are needed to ensure staff: understand girls’ PA motivation, create an autonomy supportive environment, and engage girls in active pursuits.

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Frederiki C. Moustaka, Symeon P. Vlachopoulos, Chris Kabitsis and Yannis Theodorakis

Background:

The present study evaluated the effectiveness of an autonomy-supportive intervention based on self-determination theory in influencing perceptions of autonomy support, basic psychological needs, behavioral regulations, subjective vitality, and exercise behavior.

Methods:

35 female exercise participants age 30 to 58 years who enrolled to an 8-week exercise program attended 24 exercise classes that were taught using either an autonomy-supportive (n = 19) or a lack of autonomy support (n = 16) instructing style.

Results:

The experimental group reported an increase in perceived autonomy support, the fulfillment of the needs for autonomy and competence, identified regulation, intrinsic motivation, and subjective vitality. They also reported higher attendance rates during the program and greater participation to moderate and/or mild nonstructured exercise during 5 weeks after the end of the program. The control group reported a decrease in perceived autonomy support, the needs for autonomy and competence, intrinsic motivation, and subjective vitality.

Conclusion:

The results supported tenets of self-determination theory and highlighted the motivational and psychological benefits of an autonomy-supportive exercise instructing style among middle-age women.

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Doug Cooper and Justine Allen

foster an ego-involving climate ( Ames, 1992 ; Nicholls, 1984 ). According to SDT, coaches who foster an autonomy-supportive motivational climate support the satisfaction of participants’ basic psychological needs (autonomy, competence, and relatedness; Deci & Ryan, 2000 ; Mageau & Vallerand, 2003