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Pilot Study on Impact on Balance of Autonomic Nervous System During Equine-Assisted Coaching: Simultaneous Heart Rate Variability in Horses, Coach, and Client

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The rhythmic pattern of heart activity, heart rate variability (HRV), was used in this pilot study to evaluate quantitatively the autonomic nervous system of humans involved in an equine-assisted coaching session. HRV is responsive to states of human caring which include the experience of compassion, kindness, and empathy in humans and animals. Results indicated that emotions in humans impact their psycho-physiological state and resulted in healthy HRV patterns. This effect was enhanced in the presence of horses during triad-coaching sessions. The study signals that integrating coaching with horses can be a catalyst for healthful benefits associated with human caring.
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Pilot Study on Impact on Balance of Autonomic Nervous System During Equine-Assisted Coaching:
Simultaneous Heart Rate Variability in Horses, Coach, and Client
Ellen Kaye Gehrke, PhD, National University; Michael P. Myers, PhD, National University; Suzanne Evans, EdD, National
University; Karen Garman, EdD, Healthcare Leadership, Education, and Performance, Inc.
Abstract
The rhythmic pattern of heart activity, heart rate variability (HRV), was used in this pilot study to
evaluate quantitatively the autonomic nervous system of humans involved in an equine-assisted
coaching session. HRV is responsive to states of human caring which include the experience of
compassion, kindness, and empathy in humans and animals. Results indicated that emotions in
humans impact their psycho-physiological state and resulted in healthy HRV patterns. This effect
was enhanced in the presence of horses during triad-coaching sessions. The study signals that
integrating coaching with horses can be a catalyst for healthful benefits associated with human
caring.
Keywords: equine-assisted therapy, autonomic
nervous, parasympathetic nervous, and
sympathetic nervous systems
Introduction
This work presents findings from a pilot study
measuring Heart Rate Variability (HRV) and
positive and negative affect in equine-assisted
coaching sessions. HRV is a noninvasive
measure used to assess the stress response in
humans. HRV studies indicate that therapeutic
interventions with horses improves the
psychological state and the physiological systems
of humans during various states of interaction
(Kaye Gehrke, 2009). The validated and reliable
PANAS (Positive and Negative Affect Schedule)
questionnaire was administered as part of the
research process (Watson, 1998). This
questionnaire consists of 20 words that describe
different feelings such as strong, alert, nervous,
and jittery and has been shown to be a valid and
reliable measure of positive and negative affect.
Positive affect has been well-associated with
physical wellness (Pressman & Cohen, 2005).
As a parallel to workplace training, the equine-
assisted coaching session focuses on the client’s
growth and development in their relationships and
career. Typically, clients participate in an activity
on the ground with horses. The trained coach
guides the experiential learning process with the
client in a safe environment (Salem, 2011).
Research has shown that coaching with horses
balances the autonomic nervous system which is
linked to reduced stress and increased variation
in HRV. Variation in heart rate is good for the
heart and the body and has been documented in
well-trained athletes (Mourot, 2004). HRV analysis
is used by the best soccer teams in the world to
care for athletes by allowing them to train better
and recover faster (Fitzpatrick, 2013). Under
stressful conditions, the body activates the
sympathetic nervous system in a ‘‘fight or flight’’
response. Variation between heartbeats is lower
as the heart starts to pump at a regular rate. The
opposite occurs when the parasympathetic
nervous system engages to counter the stress
and relax and repair the heart and body. Variation
between heartbeats is higher and the
sympathovagal balance is restored.
Equine-assisted coaching sessions fall within
the realm of animal-assisted therapies within the
mind-body domain of complementary and
alternative medicine (CAM). Scientific evidence
for CAM practices is often limited, and this lack of
reliable data makes it difficult to make informed
decisions about using integrative health
modalities. This research study addressed that
lack by examining the physiological relationship in
equine coaching sessions between coach, client,
and horse. It also exposed clients to the caring
and therapeutic effects of animals and nature.
Theoretical Framework
An important aspect of human caring
concerns the dynamic relationships between
clinicians and patients. It is well-known that
equine-assisted coaching sessions have provided
profound shifts in individual and group
awareness, mindfulness, resilience, and
compassionate behavior. Horses do the work of
healing through a variety of interactions (Salem,
2011). It is speculated here that using a
quantitative marker (HRV) can prove more
scientific as a measure of the human-horse
interaction.
When there is a balance in the autonomic
nervous system, as determined by HRV, research
demonstrates that there is more clarity of thinking,
focus of attention, increase in confidence,
improved decision-making, and reduced stress
and anxiety (McCraty, 2006). There is little
research on the physiological aspects of coaching
interventions. Our research examined the
physiological relationship between the coach and
client and then between the coach, client, and
horse. The goal of this work is to determine
technological approaches to measuring caring
related outcomes in equine-assisted coaching
sessions.
Method
The study was conducted at Rolling Horse
Ranch in Ramona, California. The study explored
the relationship between HRV, positive and
negative affect, and the engagement of horses in
a coaching relationship. Two coaching pairs were
examined. One with just a coach and client (dyad
team) and one with a coach, client, and horse
(triad team). Both teams wore a heartrate monitor
during a 45 min to 2 hr coaching session. A pre
and post self-assessment of leadership
competencies using the PANAS questionnaire
was administered during each session.
Participants indicated by Likert scale the extent to
which they felt a certain affect. Results were
transformed to all be in the positive direction of
affect (e.g., disagreement with a negative affect
was reflected as a positive value) so they could
be analyzed in one charting.
For HRV data collection, the participants’ and
horses’ electrocardiography (ECG) were recorded
with a Polar Equine RS800CX G3 ambulatory
ECG recorder set. Each set consists of a Polar
Equine RS800 Heart Monitor with software, a
receiver, a Human HR Monitor, and a Polar
WINDlink remote 30 feet transmission USB
antenna to transmit the ECG signal from the
horse to the receiver. The timing of the three ECG
monitors was synchronized during the recording
periods. Data from the monitors were transferred
to a password-protected PC using Polar Pro
Trainer 5 software. The transferred data were
then analyzed by Kubios software (Tarvainen,
2009). The software allows one to measure the
exact R to R (time interval between R waves,
measure of HRV) intervals between heartbeats of
the QRS (complex that represents combination of
three of graphical deflections seen on ECG that
denotes ventricular contraction) complex from the
ECGs. HRV was measured by the software which
calculated SDNN (standard deviation of the
normal to normal heartbeats), pNN50 (measures
the percent of R to R intervals that greater than
50 milliseconds [ms] away from their adjacent
interval), and the low frequency to high frequency
ratio (LF/HF) frequency domain analysis value
(ratio of sympathetic to parasympathetic activity).
Another analysis of HRV that was performed
involved making a Poincar´
e plot of the data. The
parameters of this plot are easy to compute via
the Kubios software and have been demonstrated
to quantify the involvement of the autonomic
nervous system in HRV (Kamen et al., 1996).
Every dot on the plot is a combination of two R to
R intervals that are right next to each other in time
(RR
n
and RR
nþ1
). Thus, points along a straight
International Journal for Human Caring12
diagonal line represent low HRV as their length
would be the same (no variation). Points falling
outside that line represent different RR intervals
and increased HRV. The width of the Poincar´
e
plot, as quantified by SD1, is a measure of short-
term variability and gets larger with greater HRV.
An even more robust quantitative analysis of the
R to R intervals involved using the Kubios
software to perform a frequency domain analysis.
This involved taking the wave forms of the R to R
intervals and breaking them down to see the
component frequencies that can be ascribed to
different involvements of the autonomic nervous
system. Low frequency (LF) waveforms reflect
contributions from both the parasympathetic and
sympathetic nervous systems. High frequency
(HF) waveforms reflect contributions from the
parasympathetic nervous system. Thus the LF/HF
ratio measures the involvement of the
sympathetic and parasympathetic nervous
system. As the ratio gets larger, the sympathetic
nervous system becomes more controlling. A LF/
HF value less than 1 indicates greater control via
the parasympathetic nervous system. Three
session times were evaluated using the following
protocol: Session 1 (Baseline with Client),
Session 2 (Coach-Client interaction before horse),
and Session 3 (time just after Coach-Client
interaction with horse).
Results
The PANAS results (Figure 1) showed an
increase in positive affect for both client and
coach during the coaching session with the horse.
The client showed a further increase with the
horse present above interacting with the coach
Figure 1
PANAS Scores from Three Sessions for
Coach and Client
PANAS ¼Positive and Negative Affect Schedule
Table 1
Heart Rate Variability Analysis Indices for Coach: Sessions 1, 2, and 3
Index Session 1 Session 2 Session 3 Standard
SDNN 44.8 120.5 109.6 104.0
pNN50 0.2 11.6 10.1 64.6
LF/HF 2.95 0.650 0.877 0.47
SDNN ¼standard deviation of normal to normal R-R intervals, where R is peak of QRS complex (heartbeat)
pNN50 ¼percent of RR intervals that are greater than 50 ms
LF/HF ¼ratio of low frequency to low frequency wave forms
Figure 2
Heart Rate Variability Analysis Results
Note. Panel A displays the RR interval time series over the entire sessions. Panel B through D are the Non Linear Analyses displayed as a Poincar´
e Plot for each session.
2016, Vol. 20, No. 1 13
Pilot Study on Impact on Balance of Autonomic Nervous System During Equine-Assisted Coaching: Simultaneous Heart Rate Variability in Horses, Coach,
and Client
alone. HRV analysis of the R to R intervals of one
heartbeat (of the QRS complex) from the ECGs
showed a clear increase in HRV during the
coaching sessions as seen in Table 1. This
analysis was done only on the coach as the
recordings from the client and the horse were not
readable. The coach’s SDNN, a direct measure of
HRV, increased from 44.8 in session 1 to 120.5 in
session 2 and then stabilized to 109.6 in session
3 with the horse involved (SDNN is measured in
ms). This final session with the horse matched the
values of a well-trained athlete (Mourot, 2004).
The pNN50, another direct measure of HRV,
increased from 0.2 in session 1 to 11.6 in session
2 and then stabilized to 10.1 in session 3 with the
horse involved.
The coach’s LF/HF ratio went from 2.95
(demonstrating stress and sympathetic nervous
system control) in session 1 to 0.650 and 0.877 in
session 2 and session 3, respectively. These
results demonstrated clear involvement of the
parasympathetic nervous system with client
interaction and with the horse interaction involved
(Table 1).
A Poincar´
e plot of the data is seen in Figure 2,
panels B through D. Figure 2 panel B shows the
Poincar´
e plot of the coach in session 1 just
starting with the client. Note the elongated influ-
ence of SD2 showing decreased HRV as evi-
denced by identical side-by-side RR values that
influence the shape of the plot to an elongated
ellipse. Note how dramatically the Poincar´
e plot
changes in session 2 when the coach and client
have been interacting (Figure 2, panel C) and
session 3 when the horse is added to the session
(Figure 2, panel D). The Poincar´
e plot changes to
a shortened ellipse displaying lower long-term
variability and greater short-term variability. The
Poincar´
e plots all show clear increased HRV with
the coach-client and the coach-client-horse inter-
action.
Conclusions
Preliminary findings of this pilot study show
favorable results for engaging horses in a
professional coaching session. There are few
studies in the literature showing physiological
relationships between client and coach. These
findings indicate that HRV as a measure of the
physiological state improved in brief one-on-one
coaching sessions. In health coaching, there are
little if any data in this area. When a horse is
added to create a triad relationship there were
HRV improvements in both the coach and the
client. Unfortunately, the data were not substantial
enough to claim that the client HRV improved
more with the horse than without. However, the
PANAS results indicate a favorable improvement
from the coach only session. It is interesting to
note that the coach’s HRV demonstrated a well-
balanced autonomic nervous system (ANS) that is
comparable to a well-trained athlete at the end of
the coaching session. The authors are
encouraged from the preliminary results and plan
further research modeling the same methodology
but expanding the sample size of professional
coaches, a range of client interests and well-
trained horses.
#We were able to measure usable HRV data
in our coaching subject
#Coach-client-horse interaction resulted in the
highest affect for our coach and client
#HRV analysis revealed increased HRV and
increased sympathetic tone with client and
horse interaction that matched a well-trained
athlete
#Further study will be needed to investigate
coach-client-horse triad team
#Health and Wellness coaching using HRV
could prove beneficial for case management
and improving health and human
performance outcomes.
References
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Author Note
Ellen Kaye Gehrke, PhD and Michael P.
Myers, PhD, Department of Health Sciences,
School of Health and Human Services, National
University, San Diego, CA; Suzanne Evans,
School of Education, National University, San
Diego, CA; and Karen Garman, Healthcare
Leadership, Education and Performance, Inc.,
San Diego, CA.
This work was supported in part by grants
from the Presidential Scholar’s Research Award
(National University, President Michael
Cunningham) and support of School of Health
and Human Services, Dean Gloria McNeal, for
the project to be presented in abstract form at the
2014 American Public Health Association’s
Annual Meeting & Exposition.
Correspondence concerning this article should
be addressed to Dr. Ellen Kaye Gehrke,
Department of Health Sciences, School of Health
and Human Services, 3678 Aero Court San
Diego, CA 92123-1788. Electronic mail may be
sent via the Internet to ekayegehrke@nu.edu
International Journal for Human Caring14
Pilot Study on Impact on Balance of Autonomic Nervous System During Equine-Assisted Coaching: Simultaneous Heart Rate Variability in Horses, Coach,
and Client
... 7 Previous research has demonstrated that equine interaction can improve heart rate variability (HRV) in executive coaching sessions with a quantifiable measure in HRV, matching the values of a well-trained athlete. 8,9 An unpublished study by the authors working with a population of children with autism indicated that the autonomic nervous system improved depending on when and how often they rode. A recent study by Lanning 10 addressed health and disabilities of Veterans engaged in a combat Veterans program. ...
... 18 In addition, recent studies with coaching pairs and horse owners have shown that HRV may prove to be a more scientific quantitative marker to measure the human-horse interaction. 8,19 Clinical research has shown that when HRV levels are high, a person experiences lower levels of stress and can respond to life with greater resiliency. When HRV is low, this is an indication of stress and lower resiliency. ...
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Heart rate variability in team sports: Brief review
  • J Fitzpatrick
Fitzpatrick, J. (2013, June 17). Heart rate variability in team sports: Brief review. Retrieved from http://www.scienceinsoccer. com/2013/06/heart-rate-variability-in-teamsports.html
Developing coherent leadership in partnership with horses-A new approach to leadership
  • E Kaye Gehrke
Kaye Gehrke, E. (2009). Developing coherent leadership in partnership with horses-A new approach to leadership. Journal of Research in Innovative Teaching, 2.
What is equine assisted learning
  • P Salem
Salem, P. (2001). What is equine assisted learning. Retrieved from http:// horsesteachingandhealing.com/different-eamodels/
This work was supported in part by grants from the Presidential Scholar's Research Award
  • Karen Garman
  • Healthcare Leadership
Suzanne Evans, School of Education, National University, San Diego, CA; and Karen Garman, Healthcare Leadership, Education and Performance, Inc., San Diego, CA. This work was supported in part by grants from the Presidential Scholar's Research Award (National University, President Michael Cunningham) and support of School of Health and Human Services, Dean Gloria McNeal, for the project to be presented in abstract form at the
Kubios HRV-A software for advanced heart rate variability analysis
  • M P Tarvainen
  • J P Niskanen
  • J A Lipponen
  • P O Ranta-Aho
  • P A Karjalainen
Tarvainen, M. P., Niskanen, J. P., Lipponen, J. A., Ranta-Aho, P. O., & Karjalainen, P. A. (2009, January). Kubios HRV-A software for advanced heart rate variability analysis. 4th European Conference of the International Federation for Medical and Biological Engineering, 1022-1025. Berlin, Germany: Springer Berlin Heidelberg.