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Protocol 

A proposed study using 
psychophysiological biomarkers to evaluate 
the effectiveness of cat-cow yoga exercise to 
reduce chronic musculoskeletal low back 
pain 
Syeda Farah Batool1,2 , Shamoon Noshad2,3  & Sadaf Ahmed1,3  
1Department of Physiology, University of Karachi, Karachi-Pakistan.   
2Department of Psychology, Malir University of Science & Technology, Karachi-Pakistan.    
3Psychophysiology Research Lab, M.A.H.Q. Biological research center, University of Karachi, 
Karachi-Pakistan.   

                                            

Abstract 
Background: Low Back Pain (LBP) is a painful condition of the musculoskeletal 
system that affects the quality of life and causes disabilities that can cease or limit 
daily life activities. Around 85% of the population has encountered LBP at least 
once in their lives. Due to sustained or improper postures, the incidence rate of 
LBP is reportedly high amongst healthcare providers worldwide. The treatments 
to manage LBP are generally some Non-steroidal anti-inflammatory drugs 
(NSAIDs), which only give short-term relief and are seemingly ineffective after a 
particular time, so higher doses are needed. This study aims to test the Cat-Cow 
yoga posture to manage LBP in longer terms. 
Methodology: It will be a uni-center randomized control trial, and the participants 
with musculoskeletal low back pain will be randomly allocated into two groups. 
Group 1 will receive the intervention, cat-cow yoga sessions, and Group 2 will get 
the general care guide. Altered levels of cortisol, substance P and beta-endorphins 
will be measured and compared at baseline and after completion of 12 weeks. 
Discussion: A practical and cost-friendly intervention that can help Back pain 
sufferers to reduce their pain. This study will determine the efficacy of a useful 
and cost-effective yoga technique to overcome the psychophysiological 
manifestations of musculoskeletal CLBP.   
 

Keywords 
Low Back Pain, Healthcare, Nurses, Substance P, Beta-endorphins. 

 

 

 

 

Citation: Batool F, Noushad S, Ahmed S. 
A proposed study using 
psychophysiological biomarkers to 
evaluate the effectiveness of cat-cow yoga 
exercise to reduce chronic low back pain. 
APP. 2021;8(2): 112-119 
 
Corresponding Author Email: 
farahbatool97@gmail.com  
 
DOI: 10.29052/2412-3188.v8.i2.2021.112-
119 
 
Received 18/05/2021 
 
Accepted 08/10/2021 
 
Published 01/12/2021 
 
Copyright © The Author(s). 2021 This  
 is an open access article distributed under 
the terms of the Creative Commons 
Attribution 4.0 International License, 
which permits unrestricted use, 
distribution, and reproduction in any 
medium, provided the original author  
and source are credited.  
 

 

Funding: The author(s) received no 
specific funding for this work. 

Conflicts of Interests: The authors have 
declared that no competing interests 
exist. 
 

https://doi.org/10.29052/2412-3188.v8.i2.2021.114
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https://orcid.org/0000-0002-8078-4524
https://orcid.org/0000-0002-9635-0202
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Introduction  
Low back pain (LBP) is a dominant reason 
for musculoskeletal discomfort globally1. 
LBP is characterized as a symptom, but in 
some cases, it is implied as a pathological 
condition with unknown etiologies 
depending on its severity and duration2. 
Low back pain is considered ‘Chronic’ if it 
persists for three months or longer than three 
months. Chronic low back pain (CLBP) is 
responsible for disability, compromised life 
quality, and absenteeism from work 
worldwide3. Approximately 70% to 85% of 
adults have complained about the 
occurrence of such pain at least once in their 
life span. CLBP can cause a higher number of 
years lost to disability than that of other 
morbidities like cancers, respiratory 
syndromes, AIDs, accidents, and childbirth 
complications, and it is categorized as one of 
the ten most potential causes that contribute 
to illness and disability by Global Burden of 
Disease (GBD)4. 
 
It is estimated that 37% of total LBP cases are 
due to strenuous physical work. Many 
occupations are said to be riskier for getting 
LBP5. Sitting is a widely identified risk factor 
of work-related low back pain. At the same 
time, other work demands such as the 
frequent lifting of heavy stuff, intense 
physical work, and improper postures are 
also potential risk factors for LBP. In 
healthcare sectors, nurses are more likely to 
suffer from injuries and work-related 
musculoskeletal illnesses, such as LBP, than 
other healthcare workers5,6. It is evident from 
prior studies that psychological, social, 
behavioral, and demographical factors are 
linked with the onset of LBP. A sedentary 
lifestyle, smoking, and age increase the risk 
of LBP. Nurses' ergonomic exposures, such 
as the extent of direct interaction with the 
patient, posture, need to lift objects or 
attendee, work-related stress, and job 

satisfaction, put them at high risk of getting 
LBP6. 
 
Along with the physical distress, LBP is also 
the reason for extended occupational leaves, 
and because of LBP, many healthcare 
professionals either switch their jobs or quit 
the profession7. The Prevalence of LBP in 
nurses is 71.85% in Asian countries8, 82.7% in 
southwest Nigeria, Africa9, 53.3% in Saudi 
Arabia10, and 69.5% in Iran11-13. In Pakistan, 
65% of nurses are suffering from LBP in a 
study conducted in Lahore14.   
 
There are various guidelines available for the 
diagnosis of non-specific low back pain. Its 
severity and intensity can be diagnosed by 
using different assessing tools or scales. 
Natural biological markers for pain could 
also be used as a diagnostic tool for the 
evaluation of LBP. Substance P (SP), 
Cortisol, and Beta Endorphins are supposed 
to be an effective sources of estimating pain 
intensity and its manifestations. Substance P 
is said to be involved in the underlying 
mechanism of intensifying the pain by 
increasing the inflammation and 
inflammatory markers15-17. On the contrary 
to this beta-endorphins, serves as an 
endogenous opioid and tend to relax the 
patient by increasing the availability of 
serotonin and dopamine in the synapse18,19. 
Kallman20 has stated in his study that 
substance P and Beta Endorphins are not 
reliable pain regulatory markers in the 
patients' saliva of chronic neuropathic pain 
as according to their results, salivary 
substance P and beta-endorphins does not 
show much inclination20.   
 
Specific guidelines were established by the 
US, UK, and other countries to treat LBP. 
These guidelines suggested different stages 
of treatment. Firstly, all guidelines 
emphasize that patients with non-specific 
LBP must learn to manage the pain 
independently and increase their physical 



 

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activities with manageable breaks. If the pain 
persists, as the second line of care, the US 
and Danish guidelines highly recommend 
non-pharmacological treatments such as 
cognitive behavioral therapy and physical 
exercises21. Yoga, aerobics, Tai Chi are 
among the highly endorsed non-
pharmacological interventions to treat non-
specific chronic LBP. The use of non-
steroidal anti-inflammatory drugs (NSAIDs) 
and other medications to cure LBP is 
discouraged by physicians and scientists 
because of their side effects and low efficacy 
in reducing pain21,22. 
 
In all the physical exercises, yoga appeared 
to be moderately effective in managing LBP. 
There are several postures of yoga that are 
practiced and recommended by 
physiotherapists and orthopedists. Still, 
there is very scarce data that proves the 
clinical significance and efficacy of yoga. A 
systemic review of many clinical trials 
suggests a moderate certainty about the 
potential of yoga in relieving pain23,24. This 
study aims to determine the effectiveness of 
yoga as a potential intervention in the 
management of LBP. Cat-cow yoga posture 
is selected for this purpose. There are two 
basic shapes your torso and spine can make: 
flexion and extension. In the simplest 
explanation, flexion is a rounded back, and 
extension is an arched back. Cat/Cow 
alternates between flexion Cat and extension 
Cow. This exercise will help to relax the 
muscles and will make them more flexible 
and mobile25. 
 

Methodology 
Study Design 
It is a uni-center Randomized controlled 
trial. Subjects from diverse ethnicities, 
educational backgrounds, and different 
socioeconomic statuses are preferred for this 
study. Subjects will be included in the study 
if they meet the eligibility criteria and have 

experienced low back pain in the last three 
months. Written informed consent will be 
obtained from each study subject after 
providing detailed information regarding 
the objectives of the study and its duration. 
Subjects will be randomly assigned to either 
control or interventional group. Outcome 
measures will be assessed at the baseline and 
after three months. 
 
Ethical Concerns 
The study will be conducted under the 
declaration of Helsinki.  All ethical protocols 
will be followed during the study, and the 
participants will obtain written consent. This 
study is consulted and approved by Ethical 
Committee with the approval number 
ERC/S20/P-001. 
 
Eligibility Criteria 
Inclusion Criteria 
Participants must meet all the following 
inclusion criteria to participate in this study. 
1. Age between 25 to 45 years. 
Answer YES to the following questions  
2. Have low back pain constantly or on 

most days for the last three months? 
3. Have you sought care from a health care 

provider due to back pain?  
 

Following scales will be used to assess the 
participants before enrolling them for the 
study. 
1. Average pain intensity will be assessed 

using the Numerical Pain Rating (NPR) 
over the past week ≥ 2 on a 0–10 
numerical pain scale. 

2. Roland Morris Disability Questionnaire 
score ≥ 426.  

3. Fear Avoidance Beliefs Questionnaire 
(FABQ) work subscale score <1927. 
 

Exclusion Criteria 
To be eligible for the study, participants 
must not: 
• Have a personal history of the following 

neurological disorders: Alzheimer's, 



 

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Amyotrophic Lateral Sclerosis, Multiple 
Sclerosis, Parkinson's, Stroke 

• Have a personal history of the following 
cardiorespiratory disorders: Congestive 
heart failure, Heart attack in past 24 
months 

• Have a personal history of the following 
musculoskeletal disorders: Rheumatoid 
arthritis, Pathologic fractures of the spine, 
avascular necrosis or osteonecrosis, 
severe osteoarthritis. Including a history 
of spine surgery or a hip arthroplasty. 

• Have active cancer. 
• Be Blind. 
• Have used narcotics or muscle relaxants 

within 30 days before study enrolment. 
• Report being pregnant, lactating, or that 

they anticipate becoming pregnant in the 
next 3-6 months. 

• Have a body mass index greater than 35 
kg/m2. 

• Have clinical depression (i.e., subjects 
who score 24 or higher on the Center for 
Epidemiology Depression Scale). 

• Report unexplained weight loss over the 
past month (>10 lbs.). 

 
Interventions 

Study Procedure 
Enrolment: Those subjects who had 
experienced musculoskeletal CLBP were 
enrolled. 
Assessment of eligibility: Subject meeting 
eligibility criteria will be included in the 
study. 
 

Baseline assessment: All the variables, i.e., 
Oswestry Low Back Pain Disability 
Questionnaire, World Health Organization 
Quality of life (WHOQOL) Questionnaire, 
Numerical Pain Rating Scale, Sadaf Stress 
Scale (SSS) will be measured at baseline. 
 
Scoring of Oswestry Scale:  

• 0% to 20%: minimal disability: The 
patient can cope with most living 
activities. Usually, no treatment is 
indicated apart from advice on lifting, 
sitting, and exercise.  

• 21%-40%: moderate disability: The 
patient experiences more pain and 
difficulty sitting, lifting, and standing. 
Travel and social life are more difficult, 
and they may be disabled from work. 
Personal care, sexual activity, and 
sleeping are not grossly affected, and the 
patient can usually be managed by 
conservative means.  

• 41%-60%: severe disability: Pain remains 
the main problem in this group, but 
activities of daily living are affected. 
These patients require a detailed 
investigation.  

• 61%-80%: crippled: Back pain impinges 
on all aspects of the patient's life. Positive 
intervention is required.  

• 81%-100%: These patients are either bed-
bound or exaggerating their symptoms28. 

 

Randomization: Subjects based on 
eligibility criteria will be randomly 
allocated to the experimental or control 
group sequentially as they agree to 
participate. 
 
Allocation: A booklet with detailed 
instructions will be provided to the study 
subjects according to the groups 
allocated. 
 
Follow-up assessment: After three 
months, all the variables measured at the 
baseline phase will be measured again.  



 

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Statistical Analysis: Pre & post-analysis will 
be conducted in this phase. 
 
Expected Outcomes 
At the end of this study and proper execution 
of the intervention, it is expected that, 

i. The subjects with musculoskeletal CLBP 
will overcome the pain and perform their 
daily tasks more efficiently. 

ii. Levels of substance P and cortisol will be 
reduced, which will help to break the 
pain cycle in the body. 

iii. Level of beta-endorphins will be elevated 
at the end of the session, which will make 
them relax and will help in further 
reduction of pain. 

 
Measures 
i. Oswestry Low Back Pain Disability 

Questionnaire: This index is considered 
a standard to assess the functionality of 
the low back. It is also a trusted tool for 
researchers and health care providers to 
evaluate the extent of disability29. 

ii. Quality of life Questionnaire: It is used 
to measure the quality of life by various 
means. It will help evaluate changes 
observed in the patients' quality of life 
and well-being before and after the 
intervention is given30. 

iii. Numerical Pain Rating Scale: To 
evaluate the intensity of pain. 

iv. Roland Morris Disability 
Questionnaire: This scale is used to 
assess mild to moderate disability in 
patients with acute, subacute, or chronic 
low back pain26. 

v. Sadaf Stress Scale (SSS): Sub-section of 
SSS (Physical Stress) will be used to 
assess the degree of stress and its 
contribution to CLBP31. 

vi. Substance P: It gets increased in the 
body in chronic pain, so it could be a 
good source of estimating the extent of 
relief from the pain before and after the 
intervention. 

vii. Beta-Endorphins: They work as opioids 
in the body and produce endogenous 
analgesia. Their elevated levels after the 
intervention will be a sign of pain relief.  

viii. Cortisol: It is a steroid hormone that 
tends to elevate during psychological or 
physical stress. 

 
Sample Size Calculation 
The required sample size for the two study 
groups with α = 0.05 and (1− α) = 0.80 was 
estimated to be 49 in each group, i.e., the total 
sample size was 98 for the two groups. The 
sample size calculator provided by the 
University of California, San Francisco 
(UCSF), Clinical and Translational Science 
Institute (CTSI) was used32. 
 
Randomization 
Subjects based imon eligibility criteria will 
be randomly allocated to the experimental or 
control group in the 1:1 ratio. Computer-
generated random numbers will be used for 
randomization. After taking the subject's 
basic information, the study center will 
provide a unique code to each included 
subject. The code will be mentioned in each 
form of each subject. 
 
Sample Analysis 
All the biomarkers (Substance P, Beta 
Endorphins, Cortisol) will be analyzed and 
processed through ELISA. 
 
Statistical Analysis 
The data will be analyzed using 2 × 2 mixed 
factorial design analysis of variance 
(ANOVA) to calculate whether there is a 
significant change in the cat-cow yoga 
therapy group among the intervention and 
control group subjects. After the 
intervention, if a higher ratio of cat-cow yoga 
therapy will be observed in the experimental 
group, the interventional impact of the five 
factors of cat-cow yoga therapy will be 
examined with further analysis. Sequentially 
for each secondary outcome, additional 



 

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ANOVAs will be used to investigate 
differences between groups at three months 
and baseline. Adjusted ANOVA will be 
performed, keeping socio-demographic and 

other variables as co-variants to determine 
whether the socio-demographic and other 
characters could result in alterations in effect 
between the two groups.  

 
 

Figure 1: Flowchart of the study procedure 

 

Discussion 
The focus of research related to pain 
management is leaning towards all the 
interventions that could be used instead of 
pharmaceutical drugs and have the same 
efficacy and convenient for use. This study 
aims to find a correlation between 
psychophysiological biomarkers and Cat-
Cow yoga posture in the management of 

non-specific chronic low back pain. 
Substance P, beta endorphins, cortisol and 
stress levels are all going to be measured and 
monitored and on these basis efficacy of the 
intervention will be judged.  Life-threatening 
events aside, people's economic statuses are 
subject to considerable effects. From 
purchasing high-cost medication to visiting 
healthcare advisors, this precarious situation 



 

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will prove to be an inconvenience to people. 
Thus, an intervention - both, maximizing 
practicality and budget-friendliness - is 
needed. The topic field of this study, 
therefore, will revolve around the efficacy of 
a convenient and cost-effective yoga 
technique, fashioned to mitigate 
psychophysiological manifestations of 
CLBP.   
 

Acknowledgement  
The author is thankful to Arooma Zehra, 

Sukaina Reza and Khudaija Reza for their 

support throughout the process.  

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