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Heart Rate Variability Biofeedback as a Strategy for Dealing with Competitive Anxiety: A Case Study


Abstract and Figures

Heart rate variability (HRV) biofeedback (BFB) is a relatively new approach for helping athletes to regulate competitive stress. To investigate this phenomenon further, a qualitative case study examined the impact of HRV BFB on the mood, physiology, and sport performance of a 14-year-old golfer. The golfer met once per week at a university lab for 10 consecutive sessions of HRV BFB training that included breathing at a frequency of 0.1 Hz. The format and duration of sessions followed the HRV BFB protocol outlined previously by Lehrer, Vaschillo, and Vaschillo. Acute increases in total HRV, low-frequency HRV, and amplitude of oscillation at 0.1 Hz were observed during biofeedback practice. This effect became stronger across sessions, suggesting increases in baroreflex gain. Following HRV BFB, the golfer achieved his personal record score for 18 holes of golf, and his mean golf score (total number of shots per 18 holes of golf) was 15 shots lower than in his previous golf season. The golfer received no golf instructions during HRV BFB training. The results of this case study suggest that HRV BFB training may help the athlete cope with the stress of competition and/or improve neuromuscular function.
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Volume 36, Issue 3, pp. 109–115
©Association for Applied Psychophysiology & Biofeedback
Biofeedback Fall 2008
Heart Rate Variability Biofeedback as a Strategy for
Dealing with Competitive Anxiety: A Case Study
Leah Lagos,1 Evgeny Vaschillo,1 Bronya Vaschillo,1 Paul Lehrer,2 Marsha Bates,1 and Robert Pandina1
Center of Alcohol Studies, Rutgers, The State University of New Jersey, New Brunswick, NJ; 2University of Medicine and Dentistry of New Jersey,
Department of Psychiatry, Piscataway, NJ
Keywords: biofeedback, heart rate variability, golf, competitive stress, optimal performance
Heart rate variability (HRV) biofeedback (BFB) is a relatively
new approach for helping athletes to regulate competitive
stress. To investigate this phenomenon further, a qualitative
case study examined the impact of HRV BFB on the mood,
physiology, and sport performance of a 14-year-old golfer.
The golfer met once per week at a university lab for 10
consecutive sessions of HRV BFB training that included
breathing at a frequency of 0.1 Hz. The format and duration of
sessions followed the HRV BFB protocol outlined previously
by Lehrer, Vaschillo, and Vaschillo. Acute increases in total
HRV, low-frequency HRV, and amplitude of oscillation at
0.1 Hz were observed during biofeedback practice. This
effect became stronger across sessions, suggesting increases
in baroreflex gain. Following HRV BFB, the golfer achieved
his personal record score for 18 holes of golf, and his mean
golf score (total number of shots per 18 holes of golf) was
15 shots lower than in his previous golf season. The golfer
received no golf instructions during HRV BFB training. The
results of this case study suggest that HRV BFB training
may help the athlete cope with the stress of competition
and/or improve neuromuscular function.
The term “heart rate variability” (HRV) refers to a measure
of the beat-to-beat changes in duration of the RR intervals
(RRIs) in the electrocardiogram (ECG). The RRI, or
interbeat interval, is the distance between one R-spike and
the next in the ECG. Psychophysiological models consider
HRV as a measure of the continuous interplay between
sympathetic and parasympathetic influences on heart rate
that yield information about autonomic flexibility and
thereby represent the capacity for regulated emotional
responding (Applehans & Luecken, 2006). The activation of
the sympathetic branch of the autonomic nervous system
(ANS) increases heart rate, while the activation of the
parasympathetic branch, primarily mediated by the vagus
nerve, slows it. Variation in heart rate can be caused by a
variety of factors, including breathing, emotions, and various
physical and behavioral changes. The heart rate changes as
well in response to internal body rhythms, many of which
reflect various homeostatic control systems. In general, high
HRV represents a flexible ANS that is responsive to both
internal and external stimuli and is associated with fast
reactions and adaptability. Diminished HRV, on the other
hand, represents a less transient, less flexible ANS that is
less able to respond to stimuli change (Giardino, Lehrer,
& Feldman, 2000). It follows that HRV may provide a
promising index of an athlete’s ability to respond to both
physical and emotional stress and thus of the capacity to
perform physically at maximal levels.
Strategies for Managing Competitive Stress
A number of stress reduction exercises have been described
in the sport psychology literature to treat child athletes’
symptoms of competitive stress. Studies have dealt with
the influence of relaxation techniques on anxiety in sport,
as well as the integration of cognitive behavioral therapies
to diffuse stress in a number of anxiety-provoking sport
situations, ranging from athletic practice to competition.
The development of mental rehearsal skills has been a staple
of traditional sport psychology interventions (Cummings &
Hall, 2002). The purpose of imagery interventions has been
to reduce state anxiety by familiarizing the athlete with a
specific sport task. Through mental simulation of a stress-
evoking situation in sport, the athlete is believed to get
the “feel” of successful sport-specific motor performances
and reduce precompetitive anxiety. Many protocols call
for athletes to vividly re-create a particular stress-eliciting
situation in their minds and draw attention to the sensation
of stress in the body. Yet the vast majority of such relaxation
techniques aim to relieve the psychophysiological symptoms
of stress rather than address the source of autonomic
imbalance in the body.
Resonance Frequency Breathing
According to Vaschillo, Lehrer, Rishe, and Konstantinov
(2002), the cardiovascular system is characterized by
specific resonance frequencies of HRV that exist at a specific
Heart Rate Variability Biofeedback
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frequency for each individual, within the low-frequency
range (0.05–0.15 Hz) of HRV. The spectral distribution
of HRV is organized into conventional frequency ranges
specified by the Task Force of the European Society of
Cardiology and the North American Society of Pacing and
Electrophysiology (1996) and in other consensus papers, for
instance, Berntson et al. (1997). The resonance frequency
for each individual can be detected as the frequency at
which maximum HRV is produced, when the system is
rhythmically stimulated at that frequency. The resonance
frequency in HR for most individuals is close to 0.1 Hz, or
about six cycles per minute.
One ready source of rhythmical stimulation to the
cardiovascular system is respiration. In a phenomenon known
as “respiratory sinus arrhythmia,” vagus nerve activity shows
a rhythmical ebb and flow associated with rate of respiration.
Breathing at about six breaths per minute activates these
resonance properties and induces high-amplitude oscillations
in heart rate at 0.1 Hz. Individual factors such as total blood
volume can render the resonance frequency slightly higher
or lower than 0.1 Hz (six cycles/minute). Resonance in the
cardiovascular system at 0.1 Hz is caused by frequency
characteristics of the heart rate closed loop of the baroreflex
system, through which blood pressure changes are modulated
by changes in heart rate (Vaschillo et al., 2002, 2006).
Breathing at one’s resonance frequency activates and
strengthens the heart rate baroreflex system and thereby
strengthens an important source of ANS modulation
(Giardino et al., 2000; Lehrer et al., 2003). Increased gain in
the baroreflex is found both acutely and chronically after
biofeedback training (Lehrer et al., 2003). HRV biofeedback
(BFB) training appears to bestow a number of benefits to the
system. These include (a) maximizing respiratory efficiency
by making blood more available when oxygen concentration
in the alveoli is at a maximum during inhalation (Giardino
et al., 2000); (b) decreasing hypoxic ventilatory response
while improving oxygen saturation and increasing resistance
to hyperventilation (Bernardi, 2001); (c) increasing the
efficiency of the baroreflexes that indirectly modulate
general emotional reactivity (Lehrer et al., 2003); and (d)
improving the ability of the cardiovascular system to adapt
to circulatory requirements (Landeau, Turcotte, Desagne,
Jobin, & Boulet, 2000). This results in a system-wide energy
efficiency and metabolic energy savings that has been
demonstrated to enhance athletic performance.
Literature Review of HRV BFB and Sports
Vaschillo and Rishe (1999) and Vaschillo, Visochin, and
Rishe (unpublished data) applied HRV BFB with resonance
frequency breathing at the Lesgaft Sport University in St.
Petersburg, Russia, to 30 elite wrestlers with encouraging
outcomes. The training group, consisting of 15 wrestlers,
performed 20 minutes of HRV BFB twice per day for
10 consecutive days. The control group, consisting of an
additional 15 wrestlers, did not perform respiratory training.
Vaschillo and colleagues found that when athletes breathed
at individual cardiac resonance frequencies, they increased
the amplitude of their heart rate oscillations. In addition,
heart rate decreased (while HRV increased), blood pressure
normalized, and skin temperature increased. Further, the
group trained in HRV BFB demonstrated a reduction in
reaction time, as well as speed of recovery in relaxation
of quadriceps muscles, as compared to no change in the
control group. Through the implementation of HRV BFB,
Vaschillo and colleagues enabled athletes to maintain a state
of autonomic balance marked by a cessation of sympathetic
dominance during competitive challenges.
Strack (2003) also examined the effects of HRV BFB on
high school batting performances in baseball. He reported
that the HRV BFB group improved greater than 60% more
in batting performance than the control group. In addition,
he found that the HRV BFB group demonstrated an increase
in the percentage of total low frequencies in the heart rate
Raymond, Sajid, Parkinson, & Gruzelier (2005) compared
dance performances of 24 Latin and ballroom dancers.
Twenty-four participants from a college dance team were
randomly assigned to an alpha-theta neurofeedback,
HRV BFB, or a no-treatment control condition. Findings
indicated that HRV and neurofeedback improved the
dance performances of individuals as compared to the no-
treatment group. The subscale of timing was increased
by neurofeedback, while the subscale of technique was
increased by HRV BFB.
All three research studies reported HRV BFB as safe with
no side effects. Yet, because of the limited evidence that HRV
BFB can be used to enhance sport performance, the sport and
psychophysiological community may justifiably question
whether these preliminary results can be replicated among
varying populations of athletes. Further research is needed
to evaluate and define the utility of HRV BFB for athletes of
multiple ages, skill levels, and sporting types.
The objective of this case study, therefore, was to evaluate
the utility of HRV BFB as a strategy for reducing competitive
anxiety in a 14-year-old golfer and to encourage further
research in this area. This study was based on the hypothesis
that HRV BFB can be used as a coaching tool for young
athletes to learn how to regulate emotions and improve their
functioning in sports practice, competitions, as well as their
Lagos et al.
Biofeedback Fall 2008
day-to-day lives. The following information will introduce
the background of the participant, methods, and findings
associated with HRV BFB training. A larger scale study with
collegiate golfers at Rutgers University is underway at our
Background of Participant
The participant in this applied case study was a 14-year-old
competitive golfer beginning his first year of high school
competition. He had played golf since the age of seven,
had been an all-state competitor in elementary and middle
school, and had lived and trained at a golf academy for
the previous two and a half years. During the golf season
prior to HRV BFB training, the participant had maintained
an average score of 91 in an 18-hole golf competition and
an average score of 70 during an 18-hole golf practice. He
attributed this discrepancy to his inability to manage stress
and anxiety during competitions and cited a general fear
of negative social evaluation. He described several panic
episodes marked by shortness of breath, rapid heart rate,
sweating, and fear of losing control while playing in golf
competitions. He experienced similar symptoms during
school exams and when speaking in front of audiences.
Panic attacks did not occur, however, in golf practice. With
his parents’ consent, the golfer sought assistance to improve
his performance in competition from a sport psychology
consultant. During the 10 weeks of HRV BFB training, the
golfer did not receive any professional golf instruction or
The 10-week HRV BFB protocol designed by Lehrer,
Vaschillo, and Vaschillo (2000) was implemented with the
participant. The protocol integrated 10 HRV BFB training
sessions that were conducted at a university lab. Each session
lasted 45–60 minutes, included four tasks (A: baseline, B and
C: biofeedback training, and D: baseline) for five minutes
each. Sessions 1, 4, 7, and 10 served as recording sessions.
In the first session, the golfer’s resonance frequency was
defined as 0.1 Hz (Figure 2). ECG and respiration were
recorded during all four tasks. In each recording session,
measures of mood and anxiety were obtained. Sessions 2, 3,
5, 6, 8, and 9 were performed without physiological record.
During sessions the participant was taught to breathe slowly
at his own resonance frequency (but not too deeply) using
abdominal and pursed lips breathing techniques. Also the
participant was asked to engage in two 20-minute breathing
practices each day at home using the “StressEraser” device
(Helicor, New York). The participant submitted a weekly log
of his score per round (e.g., 18 holes) in golf competition to
the experimenter.
Psychological Measures
The Profile of Mood States (POMS): The 65-item POMS
measures six mood states, including anger, confusion,
depression, fatigue, tension, and vigor, and yields one
overall score. The POMS possesses high levels of reliability,
with alpha coefficients from 0.80 to 0.91 (McNair, Lorr,
& Droppleman, 1971). Further, the POMS has been used
extensively in sport psychology research with over 250
sport-related published papers since its introduction (LeUnes
& Burger, 1998).
Because the POMS did not address the full range of
positive mood states that also influence sport performance,
Figure 2. Profile of Mood States (POMS) form. Results on POMS demonstrated
significant improvements in tension, anger, depression, and fatigue through
HRV BFB training.
Figure 1. Participant’s resonance frequency determination. To determine
resonance frequency, the participant was asked to breathe following the pacer
at five frequencies, including 4.5, 5.0, 5.5, 6,0, and 6.5 breaths per minute.
HR and respiration frequency spectra and transfer function (TF) between
respiration as the input and RRIs as the output were calculated separately
for each frequency. The TF was computed as a quotient through dividing HR
spectral power by respiration spectral power at each frequency. Thus, the TF
shows HR response to respiration when participant breathes at each frequency
with the same depth of breathing. Resonance frequency is where the TF is at
the maximal value.
Heart Rate Variability Biofeedback
Fall 2008 Biofeedback
such as confidence and calmness (Hanin, 2000), the
Competitive State Anxiety Inventory (CSAI-2) was used to
assess participants’ affect and cognitions about competition.
Developed by Martin et al. (1990), the CSAI-2 consists of
27-items, each rated on a Likert scale from 1 (“not at all”) to
4 (“very much so”). The 27 items represent three nine-item
subscales, including somatic anxiety, cognitive anxiety, and
self-confidence. Each scale yields a separate score ranging
between 9 and 37. Alpha coefficients ranging between 0.79
and 0.90 demonstrate a high degree of internal consistency
for the CSAI-2 subscales.
Physiological Measures
A J&J Engineering (Poulsbo, WA) I-330 DSP-12 physiograph
unit was used to collect ECG and respiration data. ECG
data were collected at a rate of 500 samples per second. To
measure ECG activity, a negative electrode was attached
to the upper part of the right arm, a positive electrode was
attached to the lower part of the left leg, and a ground
electrode was attached to the upper part of the left arm. To
record respiration, we used two strain gauges: one placed
around the abdomen at the level of the navel, and one at the
level of the upper chest (thoracic placement). As the gauge
stretched, the voltage across the tube changed, and relative
changes in length were measured with a range of 0–100
units of relative strength.
Performance Measures
To measure golf performance, the participant recorded
his weekly score per golf round. This score represents the
number of strokes required to complete 18 holes of golf.
He recorded his weekly golf scores for 10 weeks each sport
Data Analysis
Raw ECG data were analyzed using the WinCPRS software
program (Absolute Alien Oy, Turku, Finland). Beat-to-beat
RRIs were assessed from the ECG signal. A spectral analysis
of RRIs and respiration was performed for each 5-minute
task. Total, low-frequency, and high-frequency HRV indices
were calculated. Cross-spectral analysis was used to calculate
coherence1 between heart rate and respiration curve.
Compared to the first baseline session, changes were found
in affect, physiology, and sport performance following HRV
BFB training.
The severity of the golfer’s self-reported unpleasant moods
was reduced following HRV BFB. As indicated in Figure 2,
the golfer showed reductions in four out of five negative
mood states between session one and session ten on the
POMS. Notably, he reported a complete absence of tension,
depression, anger, and fatigue after 10 weeks of training.
There was a minimal decrease in vigor, from a score of 14
to a score of 12. There was no reported change in confusion,
which remained at a four. The golfer’s cognitive and somatic
anxiety was also reduced, as measured by the CSAI-2. As
demonstrated in Figure 3, cognitive and somatic anxiety
scores were 14 and 21 in the first session, respectively; the
golfer reported experiencing no cognitive or somatic anxiety
in the final session. Self-reported confidence increased from
a score of 4 to 26 through HRV BFB training. A score of
4 in the initial session indicated that the golfer had lower
confidence than the average high school male athlete (M
= 24.5, SD = 5.52; Competitive Anxiety in Sport, 1990). A
score of 26 in the tenth session demonstrated that the golfer
possessed higher confidence than approximately 50% of
high school male athletes.
High-amplitude 0.1Hz oscillations in heart rate, blood
pressure, and vascular tone at the golfer’s resonant
frequency also were elicited during HRV BFB. The phase
shift between HR oscillation and the respiration curve at 0.1
Hz was close to 0°, that is, HR increased during inhalation
and decreased during exhalation (Figure 4). Heart rate
was synchronized with respiration with a coherence equal
1 Cross-spectral coherence assesses the interrelationship and overlap in
spectral properties of two time series. High coherence between respiration
and HRV would occur if a large component of HRV consists of respiratory
sinus arrhythmia. In normal breathing rates, spectral coherence is generally
high in the high-frequency HRV range (0.15–0.4 Hz).
Figure 3. Competitive State Anxiety Inventory (CSAI-2). A comparison between
pre and post scores on the CSAI-2 revealed that the golfer felt markedly less
anxious prior to golf competition and significantly more confident about his
ability to perform.
Lagos et al.
Biofeedback Fall 2008
to 0.983. Results show that total HRV2 (Figure 5a) and LF
HRV (Figure 5b) considerably increased during HRV BFB
procedure. This effect became stronger across sessions. HF
HRV (Figure 5c) decreased during the HRV BFB procedure
(tasks B and C) in comparison with baseline (tasks A and D),
whereas it considerably increased across sessions. Results
show that total, LF, and HF HRV in baseline (task A and D)
cumulatively were increasing.
Sport Performance
As illustrated in Figure 6, there was a reduction in mean golf
scores after 10 weeks of HRV BFB training. In the season
prior to training, the golfer completed an 18-hole golf
competition in 91 strokes on average; in the season following
training, his mean score decreased to 76 strokes.
Discussion and Future Directions
Training in HRV BFB was followed by large acute and
chronic effects on indices of autonomic function, decreases
in anxiety and various other negative mood states, and
improved athletic performance in this young elite athlete.
The mechanism for emotional and performance effects may
be biofeedback effects on autonomic regulation. HRV BFB
elicits high-amplitude oscillations in the cardiovascular
functions, which in turn train autonomic reflexes (Lehrer et
al., 2003). The increase in LF and total HRV within sessions
reflects resonance effects. The increases in LF HRV at task
A across sessions may reflect increased resting baroreflex
gain. The large increase across sessions at task A in HF HRV
suggests a longer-term increase in vagus nerve activity.
There is evidence that HRV BFB elicits high-amplitude
oscillations in cardiovascular functions, which in turn trains
autonomic reflexes (Lehrer et al., 2003). This training restores
autonomic balance and improves autonomic control that
supports emotional regulation and movement coordination.
2 High-frequency HRV (HF HRV) is defined as the frequency component
from a Fourier analysis between 0.15 and 0.4 Hz. It usually reflects
respiratory sinus arrhythmia, which is mediated by the vagus nerve. Low-
frequency HRV (LF HRV) is the component between 0.05 and 0.15 Hz; it
appears to have both sympathetic and parasympathetic mediation and is
highly correlated with baroreflex activity (Task Force, 1996; Berntson et
al., 1997).
Figure 5. HRV indices across tasks (A, B, C, D) and sessions (1, 4, 7, 10).
Increase of total HRV, LF HRV, and HF HRV indices across sessions supports the
hypothesis that 10 weeks HRV biofeedback training cumulatively activates and
improves autonomic function regulation.
Figure 4. Example of heart rate-respiration synchronization. High synchronization
is an evidence that participant was breathing at resonance frequency.
Heart Rate Variability Biofeedback
Fall 2008 Biofeedback
Future Directions
The golfer’s weekly homework logs indicated regular and
consistent practice for two 20-minute sessions, six days per
week throughout the study. In addition, the golfer reported
implementing breathing skills as needed on the golf course.
We note that the notion that other golfers, or athletes of
any sport type, are able to automatically transfer skills
learned in the laboratory to sport performance is not yet
supported by evidence. According to the deliberate practice
theory, expertise is generated from the development of
domain-specific knowledge structures and skills acquired
through the process of adaptation and practice (Singer and
Janelle, 1999). The development of an automatic process of
resonance breathing may be possible but would likely involve
extensive, massed practice (consistent stimulus-response
mapping) in relevant emotional states and environmental
contexts. Further questions concern how biofeedback skills
should be taught, applied, and practiced in sport.
Future research may also extend beyond the physiological
and psychological domains to include other interesting and
important aspects of young athletes’ lives. Indices such as
substance use, academic grade point average, and number
of skipped sport practices would be important measures to
gauge how the development of self-regulation skills help
define behavioral outcomes.
Caveats and Limitations
It is uncertain whether the immediate training effects of
HRV BFB amplify, decrease, or remain consistent over time.
Longitudinal research is important for several reasons,
the foremost being that researchers lack an understanding
of how long the effects of HRV BFB endure after training
sessions have terminated. Second, individuals learn skills at
different rates, and thus, some athletes may not acquire self-
regulation skills until the tenth session or later. Assessments
of the effects of HRV BFB over durations that exceed 10
weeks are needed, as is research on the utility of booster
HRV BFB sessions following massed training.
The general aim of this study was to demonstrate that HRV
BFB is a viable method of improving golf performance,
perhaps by reducing competitive anxiety. A detailed
understanding of the participant and the psychological,
physiological, and sport performance–related findings were
presented to highlight the utility of this approach for child
athletes. Within this general aim, several aspects of the
methodology were described, including (a) the design of the
study, (b) session format and structure, and (c) measures for
assessing emotional, physiological, and sport performance
changes. Accumulated data suggested that HRV BFB
training may have enhanced the golfer’s ability to cope with
stress and increased his ability to perform optimally during
competition. HRV BFB elicited resonant oscillations in the
cardiovascular system and apparently normalized autonomic
regulation. As such, these techniques may have been
responsible for the substantial improvements in the athlete’s
mood and confidence, reduced the stress he experienced
during competition, and enhanced his golf performance. It
is hoped that the potential benefits of HRV BFB for athletes
of varying ages, skill levels, and sport disciplines undergo
investigation in controlled experimental studies to define
the mechanism(s) of action and advance the development
of outcome measures, strategies, and methods to implement
HRV BFB in sport settings.
This study was supported, in part, by NIDA grant P20
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Correspondence: Leah Lagos, Center of Alcohol Studies, Rutgers, The State
University of New Jersey, 607 Allison Road, Piscataway, NJ 08854, email:
Leah Lagos Evgeny Vaschillo Bronya Vaschillo
Paul Lehrer Marsha Bates Robert Pandina
... Studies have been conducted on the effects of HRV biofeedback training in different sport branches. For example, in case studies examining the effects of HRV BF training, increase of HRV and LF and golf performance was observed in female golfers (Lagos et al., 2008, Lagos et al., 2011. HRV (Standard Deviation NN Intervals (SDNN), low frequency (LF), high frequency (HF), LF/HF ratio) of athletes increased after HRV BF training in the pilot study with elite squash and tennis athletes (Park et al., 2020). ...
... Subsequently, the participant was instructed to breathe at their resonant frequency and relax. Breathing frequencies were set to be rhythmic at six breathing cycles per minute (0.1 Hz) (Hassett et al., 2007, Lagos et al., 2008, Lehrer et al., 2003, Lehrer et al., 2006, to promote coherence within the body and to achieve optimal performance. All HRV-BF training sessions were conducted twice a week for 10 weeks, with at least a day in between each session. ...
... LF increased in the follow-up tests after HRV BF training, increased during sessions in the HF experimental group, and decreased after BF training. In a case study examining the effects of HRV BF training (once per week for 10 consecutive sessions; each session lasted 45-60 minutes) on the sports performance, mood, and physiology of a 14-year-old golfer, the total HRV, LF, and HF increased with sessions (Lagos et al., 2008). Another case study with a golfer showed that RMSSD and HF values increased in the 7th and 10th sessions compared to the 1st and 4th sessions with 10 weeks of HRV BF training. ...
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The objective of the present study is to investigate the effects of ten-weeks heart rate variability biofeedback training on the basketball skill, free throw, and heart rate variability parameters. We aimed to increase vagal activation and to assess its effects on basketball performance and heart rate variability parameters . Twenty-four basketball players (experimental, n=12 and control, n=12) aged 18–24 volunteered to participate in this study. The experimental group participated in a ten-weeks heart rate variability biofeedback and basketball training program, while the control group participated only in a ten-weeks basketball training session. Basketball free-throw performance, basketball skills, and heart rate variability tests were applied to the experimental and control groups before and after ten-weeks of the intervention. We found that basketball free-throw performance, breathing frequency and heart rate variability parameters that reflect vagal modulation of parasympathetic activity improved in participants who underwent the ten-weeks heart rate variability biofeedback and basketball training, and not in those who underwent basketball training only. Finding suggest that heart rate variability biofeedback, along with basketball workouts, may contribute to better basketball free-throw performance potentially via improved autonomic nervous system functioning.
... By learning to elevate HRV through BF training, participants can improve their ability to regulate emotional and physiological responses to stress. Several studies have been conducted on HRV-BF training effects in different sports branches; for example, in case studies examining HRV-BF training effects, an increase in HRV, low frequency (LF), and golf performance were noted in collegiate golfers (Lagos et al., 2008, Lagos et al., 2011; HRV Standard Deviation NN Intervals (SDNN), LF, high frequency (HF), LF and HF ratio of athletes increased after HRV-BF training in a pilot study with elite squash and tennis athletes (Park et al., 2020). noted the positive effects of 10-session HRV-BF training on 30 basketball players; in this study, anxiety was reduced while performance improved. ...
... Our findings agree with the following previous work: e.g., In the study of , the HRV-BF group showed a significant improvement in passing and shooting values. In a case study (Lagos et al., 2008) examining the effects of HRV-BF training on the sports performance, mood, and physiology of a 14-year-old golfer, LF, and HF increased with sessions. A review by Morgan and Mora (2017), evaluating the effects of HRV-BF on athletic performance, stated that there was an improvement in psychophysiological variables and an increase in performance in 86% (n = 6) of the studies. ...
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The purpose of this study is to investigate the effects of 10-week heart rate variability biofeedback training on basketball skills, free throws, and heart rate variability parameters. Twenty-four basketball players (experimental, n = 12 and control, n = 12) aged 18–24 years volunteered to participate in this study. The experimental group participated in a 10-week heart rate variability biofeedback and basketball training program, while the control group only participated in the 10-week basketball training session. Basketball free-throw performance, basketball skills, and heart rate variability tests were conducted on the experimental and control groups before and after the 10-week intervention. Consequently, we discovered that basketball free-throw performance, breathing frequency, and heart rate variability parameters, which reflect vagal modulation of parasympathetic activity, improved in participants who underwent the 10-week heart rate variability biofeedback and basketball training, and not in those who took basketball training only. Our findings propose that heart rate variability biofeedback, alongside basketball workouts, can contribute to better basketball free-throw performance potentially through improved autonomic nervous system functioning. Keywords Basketball performance · Heart rate variability · Basketball free-throw · Biofeedback
... Although there have been studies that have examined the effect of competitive anxiety on sport performance (Lagos et al., 2008) and baseball specifically (Chang & Torres, 2019;Chen et al., 2019;Han et al., 2014;Strack, 2003), very few studies have examined the influence of hardiness on a player's anxiety and performance in baseball. The current study provides contributions to further understand the influence of hardiness on objective performance statistics in the presence of competitive anxiety intensity, as was recommended by Hanton et al. (2013). ...
... Using the sub-construct of commitment, one's ability to persist in whatever one is doing, even when stress rises (Kobasa, 1979), practitioners could help pitchers re-focus their commitment through imagery or breathing when they feel they are in those situations. As found in a previous study that identified that breathing helped decrease heart rate variability and improved performance on the golf course (Lagos et al., 2008), a similar focus on the breath within a routine could help refocus the pitcher's sense of commitment. Additionally, practitioners should focus on improving pitcher's metacognition of their own commitment during performances as discussed in MacIntyre et al.'s article (2014). ...
The purpose of this study was to explore the moderating effect of hardiness on the relationship between trait anxiety and objective performance within NCAA Division I collegiate baseball players. An updated and shortened version of the Personal Views Survey (PVS III-R) was used to measure hardiness after a confirmatory factor analysis (CFA) was conducted. Of the total 389 players that participated, 171 met inclusion criteria and were split into two groups – hitters (N = 94) and pitchers (N = 80) – to identify differences in skills and how sub-constructs of hardiness (commitment, control, challenge) affected performance through a descriptive correlational design. The results show significant moderating effects of commitment for pitchers that accounted for the majority of variance in the relationship between perception of trait anxiety intensity and left on base percentage (LOB%) and wild pitches (WP). For hitters, significant moderating effects of control accounted for less variance in the relationship between perception of trait anxiety intensity on batting average on balls in play (BABIP) and grounding into double plays (GDP). The findings indicate there may be significant moderating effects of hardiness on the relationship between trait anxiety and objective performance that may be present in game situations with runners on-base. Practitioners could use these findings to target mental skills that could develop a pitcher’s commitment or hitter’s sense of control to enhance their performance within baseball-specific situations. For example, mental performance consultants could help athletes reframe the intensity of cognitive or somatic anxiety during situations with runners on-base.
... The fact that a decrease in anxiety, both at the cognitive-behavioral and at the psychophysiological level, is associated with an increase in self-efficacy that underlines how the promotion of self-confidence is indirectly, but significantly, promoted by a BFB intervention. Furthermore, the improvement in sports performance (measured by dribbling, passing, and shooting tests) confirmed other studies already present in the literature involving wrestlers, dancers, baseball players, and golfers (Lagos et al., 2008;Raymond et al., 2005;Strack, 2003). This aspect could be attributed to the HRV-BFB procedure that causes resonance in the cardiovascular system and provides an athlete with a better ability to manage anxiety, which can be used during times of stress such as training and matches. ...
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Stress is a psychophysical condition that causes an impairment in athletes' performance by causing an increase in sympathetic activity and an autonomic imbalance. The current methods for the measurement of psychophysiological stress introduce the use of the heart rate variability as a useful index of the well-being of these people. The heart rate variability corresponds to the time intervals between consecutive heartbeats, such as an irregularity in the normal sinus heart rhythm whose variability is due to the control exercised by a complex system of mechanisms, including the respiratory control system, and provides information about the activity of the sympathetic and parasympathetic branches of the autonomic nervous system. This review aims at summarizing the promising results, despite small amount, of the recent literature on the efficacy of heart rate variability biofeedback on the autonomic imbalance and psychophysical well-being of athletes as well as cognitive and motor performance.
... Heart rate variability (HRV) refers to the variation in RR intervals, the time between the R-spikes of consecutive heartbeats, measured in milliseconds. 22 With HRVB, individuals obtain more control over their HRV and try to find coping skills to stress or calm down to advance in the game. HRV is used as a measure of stress because it is a reliable indicator of the actual stress level 23 and the selfregulatory strength, important for stress mindset. ...
Background: Performance levels in football are ever more important and no longer are just physical, technical, and tactical skills, the ones that make an athlete stand out. Cognitive variables, such as stress-coping, become more important and seem to be explaining differences in performance, for example, through reaching an optimal level of arousal. In addition, it is suggested that stress-coping skills also affect situation awareness (SA), important for decision-making in the complex and dynamic situations in football. Objective: This study was conducted to examine how stress-coping skills, such as stress mindset, affect performance and SA in the context of a football match. Methods: Twenty elite female football players participated in the study. The final sample size consisted of 15 players for the Stress Mindset Measure (SMM) analysis and 8 players for the multilevel model analyses. Two types of intervention were used to manipulate stress mindset and control over heart rate variability (HRV); a serious game called "Stressjam," and a reflection tool called "Brainjam." Questionnaires for stress mindset and SA and video analysis for performance were used. A total of three matches were assessed. Results: The "Stressjam" intervention resulted in significant differences in stress mindset throughout the intervention [F(1,5) = 7.357, P = 0.008]. Subsequently, multilevel analysis showed a positive, strong, and significant correlation between stress mindset, manipulated through "Stressjam" and SA [r(14) = 0.69, P = 0.014]. A correlation of practical interest, given the confidence intervals, was found between stress mindset, manipulated through "Stressjam," and performance. Conclusion: Cognitive variables, such as stress-coping, correlate significantly with SA in football. A correlation of practical interest was found between stress-coping and performance. Further research is needed to study the relationship between stress-coping and performance in football.
... For example, sometimes, sports psychologists use cognitive reconstruction methods such as image training (Lagos et al., 2008) and interventions correcting cognitive misinterpretations (Colic et al., 2020) to simulate athletes in competition situations, so that athletes are mentally prepared and experienced and become less anxious. Thus, athletes can concentrate faster and quickly recover from frustrations (Peper and Aita, 2017). ...
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Research background Twisties symptoms have attracted the world's attention in the sports field since the 2020 Tokyo Olympics. Aim However, studies on the symptoms and causes, inducing mechanisms, and relationships between DP/DR (Depersonalization/Derealization Disorder) and anxiety and depression for athletes have been sparse for both the general population and athletes. The literature on the twisties issue of athletes is quite scarce in the past. Research method Adopting the criteria appealing to PRISMA Items to review the subject twisties in a broader mode and combing with the IPO (Input-Process-Output) model for triangulation testing purpose, this study categorized the literature to explore input variables causing athletes’ twisties and identified process variables in psychological mechanisms bridging suppression and finally discussed the existing possible ways in helping athletes to solve problems caused by twisties. Results The authors formed 6 propositions in summarizing twisties' influential factors and mechanisms and tried to propose solutions to reduce the stress and the relevant twisties symptom of athletes. (1) Promotion of Athletes' Mental Toughness to Resist Stressors. (2) Interventions that correct for cognitive misinterpretations and appropriate relaxation and mindfulness practice in correcting a range of attention might reduce DP/DR. (3) Monitoring the athlete's HRV test results to ensure the Athlete's ability to resist pressure. (4) Avoid organizational stressors. (5) Written Emotional Disclosure method. (6) Improve various support systems for athletes: dual career paths. (7) Athletes' Stressful Awareness about the impact of gender, seniority, and environment. Conclusion Through the theoretical dialogue on the symptom of twisties, this study helps promote the development of the research of “twisties” and depersonalization-derealization symptoms (DDS); both have been under-researched.
... HRV refers to the variation in the R-R intervals (highest point of activity of the cardiac cycle) and indicate the interval between one heartbeat and another (De Witte et al., 2019) and it has various causes such as changes in breathing rhythm, physical, behavioral, and emotional changes. Unlike heart rate, a higher HRV indicates the ideal interaction among SNS and PNS (Lagos et al. 2008). Therefore, HRV is sensitive to the identification of alterations in the SNS and PNS in stressful situations. ...
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Wearable devices use sensors that continuously capture physiological signals and, once processed, allow the monitoring and development of interventions in various areas of health, including mental disorders. In Clinical Psychology, this type of technology can cooperate to the objective and continuous measurement of stress, as well as to generate feedback when stressful situations occur. This narrative literature review focused on these devices, presenting the main scientific data available, as well as opportunities and difficulties in implementing these devices in stress assessment and health treatments. The reviewed research indicated that it is necessary to develop more robust and theoretically based systems that integrate physiological, subjective and contextual responses to implement this type of wearable in clinical contexts. However, the accuracy already demonstrated by wearable sensors in laboratory situations and some continuous monitoring tests, reinforce that these are tools with great potential for application in clinical psychological practice.
... Evgeny and his colleague Paul Lehrer were early pioneers in the study of resonance paced breathing and the development of HRV biofeedback (Lehrer et al., 2000;Vaschillo et al., 2002. Their work has inspired the application of HRV biofeedback in a variety of clinical populations such as those affected by asthma, hyper-and hypotension, fibromyalgia and depression, and other disorders Karavidas et al., 2007;Lagos et al., 2008;Lehrer et al., 2006. As well, both HRV biofeedback and slowpaced breathing show substantial efficacy in reducing subjective stress and anxiety (Goessl et al., 2017). ...
The present study investigated the effects of a psychophysiological intervention programme consisting of heart rate variability biofeedback (HRV BFB) and cognitive restructuring (CR) on the self-regulation skills of an 18-year-old female squash athlete on the Korean national team. The participant participated in 10 sessions of the programme in a laboratory. The HRV was measured during 10 minutes of natural breathing to set a baseline and for breathing training on a BFB device. In addition, two questionnaires, namely, the competitive state anxiety inventory-2 (CSAI-2) and the cognitive emotion regulation questionnaire (CERQ), were used to measure the participant’s psychological state. Descriptive statistics were reported to see the changes in HRV and psychological state between the initial test and post-test, and the qualitative results indicated improvements in the participant’s self-regulation skills to change her negative thoughts. In conclusion, this programme could be effective in enhancing self-regulation in athletes.
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مقدمه و هدف: یکی از مهمترین اهداف هر ورزشکاری اجرای عملکرد بهینه در حین مسابقات است، از شیوه های نوین و رو به گسترش برای بهبود عملکرد ورزشی بازخورد زیستی (بیوفیدبک) می باشد. هدف پژوهش حاضر بررسی تاثیر تمرینات بیوفیدبک بر برخی عوامل فیزیولوژیک و عملکرد ورزشکاران ماهر تیر و کمان بود. روش شناسی: تحقیق حاضر از نوع نیمه تجربی با طرح پیش آزمون - پس آزمون با گروه کنترل بود. 24 نفر ورزشکار با میانگین سنی 5/22 سال بصورت هدفمند از بین شرکت کنندگان در مسابقات تیرانداری با کمان رنکینگ کشوری انتخاب شده و بصورت تصادفی در دو گروه 12 نفری تمرین بیوفیدبک و کنترل قرار گرفتند. بعد از پیش آزمون (آزمون عملکرد تیراندازی)، ورزشکاران گروه تجربی ابتدا 10 جلسه به تمرینات بیوفیدبک مربوط به کنترل ضربان قلب و کنترل تنفس براساس پروتکل تمرینی پرداختند و سپس، 10 جلسه همین تمرینات را همراه با هدایت رسانایی پوست انجام دادند. گروه تجربی و گروه کنترل در این بازه زمانی تمرینات مهارتی تیراندازی خودشان را زیر نظر محقق ادامه دادند. پس از 20 جلسه تمرین پروتکل بیوفیدبک دوباره آزمون عملکرد تیراندازی با همان شرایط پیش آزمون از هر دو گروه کنترل و تجربی گرفته شد. یافته ها: نتایج نشان داد که ضربان قلب شرکت کنندگان در شرایط تنش و استرس بیشتر از حالت استراحت می‌باشد(05/0 p˂). همچنین مقادیر ضربان قلب گروه تجربی در پس آزمون در شرایط استرس کمتر از گروه کنترل می باشد. نتایج تحلیل کوواریانس نشان داد که عملکرد آزمودنی های هر دو گروه نسبت به پیش آزمون پیشرفت داشت، ولی گروه تجربی عملکرد بهتری نسبت به گروه کنترل داشتند (P<0/05). نتیجه گیری: با توجه به یافته های این پژوهش، بایستی نقش تمرینات بیوفیدبک بیش از پیش مورد توجه قرار گرفته و تأکید بر استفاده از آن در کنار سایر پروتکل های تمرینی پیشنهاد می گردد.
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A therapeutic method includes determining heartbeat and respiratory rates converted in respective electric signals of a subject, displaying the heart rate, spectrally analyzing the respiratory and heartbeat signals, thereby defining a phase shift therebetween, causing the subject to modify the respiratory rate in a sense tending to minimize the phase shift and selecting a frequency of the displayed reference signal which correlates with the modified respiratory signal, and establishing an optimum reference signal displayed as a resonance frequency unique for the subject upon approaching the zero phase shift between the heart signal and the modified respiratory signal
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Attentional processing biases have been demonstrated in trait anxious individuals. The current study evaluated the interaction of trait anxiety and attentional bias in the regulation of cortisol responses to threat cues. Undergraduates (N=63) completed a dot-probe task featuring social threat words. Trait anxiety was associated with avoidance of threat cues. Attentional avoidance predicted decreased cortisol responses at higher levels of trait anxiety, and elevated cortisol responses at lower levels of trait anxiety. The results suggest that attentional processes are involved in the regulation of physiological arousal for anxious individuals.
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The purpose of this study was to examine the influence of competitive level on an athletes' use of imagery in the off-season, and to examine whether their use of imagery was related to their physical and technical preparation. Three hundred and twenty-four regional, provincial, and national level athletes were recruited to participate in this study from 10 different sports. Participants were asked to complete a modified version of the Sport Imagery Questionnaire (SIQ; Hall, Mack, Paivio, & Hausenblas, 1998) that was designed to reflect an athletes' use of imagery in the off-season. MANOVAs indicated that competitive level differences existed in athletes' use of imagery in the off-season, as well as in their use of physical and technical preparation for the up-coming season. More specifically, provincial and national level athletes engaged in significantly more imagery, regardless of the function, and physical and technical preparation then regional level athletes. In addition, bivariate correlations indicated that the more physical and technical preparation athletes engage in during the off-season, the more imagery they use.
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Components of heart rate variability have attracted considerable attention in psychology and medicine and have become important dependent measures in psychophysiology and behavioral medicine. Quantification and interpretation of heart rate variability, however, remain complex issues and are fraught with pitfalls. The present report (a) examines the physiological origins and mechanisms of heart rate variability, (b) considers quantitative approaches to measurement, and (c) highlights important caveats in the interpretation of heart rate variability. Summary guidelines for research in this area are outlined, and suggestions and prospects for future developments are considered.
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Heart rate and blood pressure, as well as other physiological systems, among healthy people, show a complex pattern of variability, characterized by multifrequency oscillations. There is evidence that these oscillations reflect the activity of homeostatic reflexes. Biofeedback training to increase the amplitude of respiratory sinus arrhythmia (RSA) maximally increases the amplitude of heart rate oscillations only at approximately 0.1 Hz. To perform this task people slow their breathing to this rate to a point where resonance occurs between respiratory-induced oscillations (RSA) and oscillations that naturally occur at this rate, probably triggered in part by baroreflex activity. We hypothesize that this type of biofeedback exercises the baroreflexes, and renders them more efficient. A manual is presented for carrying out this method. Supporting data are provided in Lehrer, Smetankin, and Potapova (2000) in this issue.
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This study describes the use of a biofeedback method for the noninvasive study of baroreflex mechanisms. Five previously untrained healthy male participants learned to control oscillations in heart rate using biofeedback training to modify their heart rate variability at specific frequencies. They were instructed to match computer-generated sinusoidal oscillations with oscillations in heart rate at seven frequencies within the range of 0.01-0.14 Hz. All participants successfully produced high-amplitude target-frequency oscillations in both heart rate and blood pressure. Stable and predictable transfer functions between heart rate and blood pressure were obtained in all participants. The highest oscillation amplitudes were produced in the range of 0.055-0.11 Hz for heart rate and 0.02-0.055 Hz for blood pressure. Transfer functions were calculated among sinusoidal oscillations in the target stimuli, heart rate, blood pressure, and respiration for frequencies at which subjects received training. High and low target-frequency oscillation amplitudes at specific frequencies could be explained by resonance among various oscillatory processes in the cardiovascular system. The exact resonant frequencies differed among individuals. Changes in heart rate oscillations could not be completely explained by changes in breathing. The biofeedback method also allowed us to quantity characteristics of inertia, delay, and speed sensitivity in baroreflex system. We discuss the implications of these findings for using heart rate variability biofeedback as an aid in diagnosing various autonomic and cardiovascular system disorders and as a method for treating these disorders.
Fifty-seven citations from the literature on the use of the Profile of Mood States scale in sport and exercise psychology research have been added to the 258 listed in a 1998 article by LeUnes and Burger that appeared in the Journal of Sport Behavior. Of the 57 updated references. 9 are from 1997, 19 from 1998, 21 are from 1999, and an additional 8 are in press at this time. It is anticipated that the 300+ references from the combined bibliographies will serve as valuable sources of data for researchers and practitioners interested in the Profile of Mood States in sport and exercise psychology.
Examined and critically evaluated current understanding of how expertise is developed by drawing on contemporary literature dealing with hereditary and genetic accounts, the influence and potential value of practice, necessary environmental conditions, and the potential interactions of these influences on motor performance. Specifically addressed are hereditary accounts of overall health and well-being, physical attributes, personality characteristics, information processing capabilities, and intelligence. With respect to the role of practice a particular mission was to focus on recent research dealing with the quality of the practice setting, rather than debating the duration needed to achieve expertise. In this respect, the role of self regulation and competitive simulation is discussed. Finally, current ideas surrounding the potential environmental influences that allow the genetic potential and practice capabilities of aspiring athletes to come to fruition are described. Conclusions are offered suggesting that to advance the understanding of expert performance beyond its current status, proponents on polar ends of the nature-nurture continuum must adopt a less confrontational, more integrative approach in future research endeavors. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
The increased prevalence of airway hyperresponsiveness (AHR) observed among athletes suggests that high-level training may contribute to the development of AHR. We investigated the possible influence of the sympatho-vagal balance on this phenomenon in 40 athletes and 10 sedentary controls. Each subject filled out a respiratory questionnaire, had a methacholine challenge, and measurements were made of their baseline plasma catecholamines [epinephrine (E), norepinephrine (NE) and dopamine (DA)] as a reflection of sympathetic tone, and their heart rate variability (SDNN: standard deviation of all normal-to-normal intervals) as an indicator of parasympathetic tone. The athletes had a 45% prevalence of AHR (defined as PC20 < 16 mg/ml, where PC20 is the concentration of methacholine inducing a 20% fall in the forced expiratory volume in 1 s, FEV1) with a mean PC20 of 21.2 mg/ml compared with 10% prevalence (mean PC20: 74.4 mg/ml) in sedentary subjects (P < 0.01). Plasma catecholamine values were not significantly different between the two groups (all P > 0.05), but the estimated parasympathetic tone was higher in athletes (P = 0.01). When data from all subjects were analyzed together, plasma E and NE correlated with PC20 (r = 0.39, P = 0.005 and r = 0.29, P < 0.005) but DA and SDNN did not (both P > 0.05). However, the ratios E/SDNN, NE/SDNN and DA/SDNN showed significant correlations with PC20 (r = 0.42, P < 0.01; r = 0.33, P < 0.005 and r = 0.31, P < 0.05, respectively) This study suggests that the sympatho-vagal balance may contribute to the increased AHR in the population studied but this influence alone cannot explain the higher prevalence of AHR in athletes.
Interval hypoxic training (IHT) is a technique developed in the former Soviet Union, that consists of repeated exposures to 5-7 minutes of steady or progressive hypoxia, interrupted by equal periods of recovery. It has been proposed for training in sports, to acclimatize to high altitude, and to treat a variety of clinical conditions, spanning from coronary heart disease to Cesarean delivery. Some of these results may originate by the different effects of continuous vs. intermittent hypoxia (IH), which can be obtained by manipulating the repetition rate, the duration and the intensity of the hypoxic stimulus. The present article will attempt to examine some of the effects of IH, and, whenever possible, compare them to those of typical IHT. IH can modify oxygen transport and energy utilization, alter respiratory and blood pressure control mechanisms, induce permanent modifications in the cardiovascular system. IHT increases the hypoxic ventilatory response, increase red blood cell count and increase aerobic capacity. Some of these effects might be potentially beneficial in specific physiologic or pathologic conditions. At this stage, this technique appears interesting for its possible applications, but still largely to be explored for its mechanisms, potentials and limitations.