Page 69 - JSOM Winter 2022

Impact of FR on Chronic Pain 1 week later, which consisted of 90 minutes of watching a
Chronic pain is defined as pain that lasts beyond the time ex- BBC documentary. The FR intervention induced marked re-
pected for healing, roughly 3 to 6 months for musculoskel- ductions in systolic blood pressure (5.3 points) and diastolic
etal injuries. Several studies have used FR as an alternative blood pressure (12.8 points) compared with mild reductions in
method for treating chronic pain. Kjellgren et al. studied the control conditions (0.7 points and 1.4 points, respectively).
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the effects of FR on participants with reported chronic neck FR participants reported statistically significant increases (p <
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pain, back pain, and stress related headaches resulting from .001) in interoceptive measures (e.g., heartbeat, breathing).
long-term muscle tension. Participants in the FR group re- As previously reported, SOs suffer from very high allostatic
ceived 45-minute FR sessions three times a week for 3 weeks, loads throughout their careers because of chronic exposure to
totaling 300 hours of FR, compared with a control cohort physiological and psychological stressors. 16,17 Future explora-
receiving no intervention. Participants in the FR intervention tions regarding the efficacy of FR on moderating these acute
group demonstrated improved outcomes, including shortened and long-term stressors in SOs are needed.
sleep onset, reduced “severest” pain intensity, and lower blood
values of noradrenaline metabolite. However, endorphin levels Impact of FR on Physiological Processes
remained unchanged in both the control and FR groups. Par- In addition to improved psychological measures, researchers
ticipants assigned to the FR group also reported that their de- have reported corresponding improvements in stress-related
gree of optimism significantly increased, while their depressive physiological outcome measures because of FR, including re-
symptoms decreased significantly. The mechanism of action ductions in cortisol levels, electrodermal response (i.e., emo-
and optimal dose for these effects deserve future inquiry, as tional arousal state), and subjective measures of pain. Other
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would a similar investigation in an SO population. However, observed benefits of FR therapy include enhanced cardiovas-
we could find no quality longitudinal studies of the use of FR cular system function, referred to as the vasodilator effect, in
for chronic pain or in an SO population. which the circulation of blood and body fluids is enhanced
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while blood pressure and resting heart rate are reduced. These
Impact of FR on Psychophysiological Measures improvements may be attributed to the reduced effects of grav-
FR therapy induces an autonomic RR that has been shown itational forces on the human body, allowing joints, muscles,
to improve many stress-related psychophysiological measures, tendons, and arteries to relax. 12,21
such as decreases in plasma and urinary cortisol measure-
ments, ACTH (adrenocorticotropic hormone) values, aldoste- Impact of FR on Performance and Recovery
rone measurements, renin activity, epinephrine levels, blood FR tanks are relatively inexpensive to purchase, maintain,
pressure measurement, and heart rate. 3-5,9 Because of acute and and administer. Previously reported benefits suggest that FR
chronic stressors, many SOs suffer from endocrine dysfunction, therapy may enhance recovery and help restore optimal per-
including overactivity of the hypothalamic-pituitary- adrenal formance following chronically high physiological and psy-
axis (HPA). HPA overactivity causes increased secretion of chological loads typical for SOs. 16,17 FR may also enhance
cortisol and norepinephrine and lower testosterone levels, perceptual-motor accuracies, such as required in marksman-
leading to sleep disruption, insomnia, chronic fatigue, and de- ship and other performance elements, required within the
pression. 17,23–25 Together, these endocrine abnormalities trans- Special Operations community. Thus, evidence suggests that
late to poorer performance. 17,23-26 FR may be an effective method to improve recovery and per-
formance in SOs. Other studies have found that FR improves
Impact of FR on Anxiety and Stress motor accuracy, reduces acute/chronic pain, improves sleep
Bood et al. examined the long-term effects of FR 4 months duration/quality, and reduces stress, depression, and anxiety.
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after treatment in 70 patients suffering from stress-related ail- Additionally, FR produces a relaxation state associated with
ments. Participants were randomly assigned in equal numbers reductions in pituitary-adrenal axis activity, resulting in re-
to either an FR or a control group. Patients each received a total duced cortisol levels, lower blood pressure measurements, and
of 12 FR or control sessions. The treatment period consisted of improved heart rate variability. 1,3,6,9
two sessions per week for 3 weeks, followed by a week with-
out treatment, followed by another 3 weeks of twice-weekly In addition to treating clinical conditions, FR has been evalu-
treatment. After treatment, patients who received FR reported ated for its ability to improve athletic performance and recov-
that sleep quality improved by 23%, optimism increased by ery. A potential benefit of FR is enhanced perceptual-motor
8.3%, stress was reduced by 31.4%, pain decreased by 48% control and accuracy, which is highly applicable to the Special
(with no other pain treatments), and depression decreased by Operations community. Perceptual-motor control accuracy
24.1%. All these benefits were maintained at 4 months post- must be sustained even when the SO is physically and men-
treatment. If similar results were to be demonstrated in an SO tally exhausted. Loss of motor control may result in mission
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population, the long-term benefits of FR could have a signifi- failure and increased risk. Before the 1990s, most research
cant impact on military operations. had focused on the effects of FR in improving gross motor
skills in athletes (e.g., tennis players, gymnasts) and had found
Feinstein et al. investigated the anxiolytic effects of FR on this treatment to be highly beneficial. 27,28 In the early 1990s,
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31 participants with stress-related disorders, including a va- Suedfeld et al reported the performance-enhancing effects
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riety of anxiety-related disorders (e.g., panic disorder, post- of FR on focus and fine motor skills in novice, intermediate,
traumatic disorder, agoraphobia). The central objectives of and expert dart throwers. This investigation sought to deter-
the study were to determine (1) the effects of FR on blood mine changes in dart-throwing accuracy, with the dependent
pressure response and (2) whether FR enhances interoceptive measure being the number of millimeters the dart landed from
(i.e., sense of the internal state of the body) awareness. Partici- the bull’s eye. Forty participants who had played darts at least
pants assigned to the FR intervention completed 90 minutes of twice the previous year were recruited to participate in this
FR, then crossed over to the control condition approximately study. Baseline dart-throwing accuracy was assessed before the

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