Role of proprioceptive neuromuscular facilitation exercises in post-COVID individuals: A randomized-control trial

Divya Gohil; Merin Shaji; Gaurang Baxi; Tushar J Palekar

doi:10.4103/jss.jss_73_22

ORIGINAL ARTICLE

Year : 2022 | Volume : 49 | Issue : 3 | Page : 277-283

Role of proprioceptive neuromuscular facilitation exercises in post-COVID individuals: A randomized-control trial

Divya Gohil, Merin Shaji, Gaurang Baxi, Tushar J Palekar
Dr. D. Y. Patil College of Physiotherapy, Dr. D. Y. Patil Vidyapeeth, Pune, Maharashtra, India

Date of Submission	04-May-2022
Date of Acceptance	09-Aug-2022
Date of Web Publication	27-Dec-2022

Correspondence Address:
Dr. Gaurang Baxi
Professor, Dr. D. Y. Patil College of Physiotherapy, Pune - 411 018, Maharashtra
India

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/jss.jss_73_22

Abstract

Background: Pulmonary function, fatigue, and chest mobility are three important parameters which are impaired after COVID-19. Manual stretching procedures have the potential to improve pulmonary function, reduce fatigue, and improve chest mobility. However, evidence regarding their effectiveness in post-COVID-19 population remains unknown. This study explores the effectiveness of two different types of stretching techniques on pulmonary function, fatigue, and chest expansion in post-COVID-19 population. Materials and Methodology: Forty post-COVID-19 patients with mild and moderate impairment were divided into two groups (20 each). Group A received hold relax proprioceptive neuromuscular facilitation (PNF) pectoral stretching while Group B received chest mobility exercises for 20 min each for 7 sessions. The outcomes measures were pulmonary function test, fatigue, and chest expansion. Results: Significant within-group differences for all outcome measures were seen at the end of intervention. Between-group analysis showed a significant statistical difference in few parameters of pulmonary function testing and chest expansion in Group A than Group B. However, no statistical significance on Fatigue after the 7 sessions of intervention. Conclusions: In COVID-19 survivors with mild and moderate impairment, hold relax PNF stretching than chest mobility exercises has a significant effect on improving pulmonary function, reducing fatigue, and improving chest expansion.

Keywords: Chest mobility, COVID-19, fatigue, proprioceptive neuromuscular facilitation, pulmonary function, stretching

How to cite this article:
Gohil D, Shaji M, Baxi G, Palekar TJ. Role of proprioceptive neuromuscular facilitation exercises in post-COVID individuals: A randomized-control trial. J Sci Soc 2022;49:277-83

How to cite this URL:
Gohil D, Shaji M, Baxi G, Palekar TJ. Role of proprioceptive neuromuscular facilitation exercises in post-COVID individuals: A randomized-control trial. J Sci Soc [serial online] 2022 [cited 2023 Jan 31];49:277-83. Available from: https://www.jscisociety.com/text.asp?2022/49/3/277/365179

Introduction

COVID-19 pandemic along with its immediate and long-term response to the pandemic are leading to an increased need of rehabilitation among the survivors of COVID-19 that includes young to older adults. As countries recover from the multiple waves of the pandemic, a multidisciplinary approach to rehabilitation is essential so as to deal with the long-term consequences of the infection and to restore function lost as a result of the direct or indirect effects of the pandemic response.^[1]

As the long-term sequelae of COVID-19 are concerned, exertional dyspnea, fatigue, and impairment in pulmonary function, and exercise intolerance is evident.^[2],[3] As the above-mentioned components are affected, this further affects the functional capacity and exercise capacity of the individuals. In the follow-up study which was already conducted in the infected individuals, it was found that there was a decline in the pulmonary function even after 3 months and 1 year, respectively. Hence, considering that the pulmonary function is decreased from a long time, it is prominent that these symptoms are found in a long term.^[4],[5] Therefore, we can conclude that COVID-19 has pulmonary impairments and should be focused. Any distortion in the chest wall determines the rhythmic and nonrhythmic movement of the rib cage during quiet breathing. This distortion further leads to decreased movement, further leading to stiffness and immobility. COVID-19 causes airway obstruction, pulmonary scarring, and fibrosis at the end stage and result in a mechanical disadvantage of the respiratory muscles.^[6]

Proprioceptive neuromuscular facilitation (PNF) stretching and chest mobility exercises for affected individuals with underlying respiratory conditions appear to be safe and effective in improving chest mobility, pulmonary function, and decrease symptoms of dyspnea and fatigue.^[7] However, its effect on the components of pulmonary function parameters such as forced expiratory volume in the 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC, fatigue and chest expansion in COVID-19 survivors however remains unknown due to lack of evidence.

This study was conducted to explore and compare the effect of PNF and chest mobility exercises on pulmonary functions, fatigue, and chest expansion in COVID-19 survivors.

Materials and Methodology

Study design, setting, and participants

This study was conducted at Dr. D. Y. Patil College of Physiotherapy, Pune. The study was approved by the Institutional Ethical Committee (Ref. no. DYPCPT/IEC/20/2021) and registered with Clinical Trials Registry of India (CTRI/2021/08/035492).

Participants

COVID-19 survivors fulfilling the following inclusion criteria were recruited:

COVID-19 recovered individuals up to 6 months from recovery
Age between 18 and 40 years with mild and moderate impairment due to COVID-19.

Participants having any musculoskeletal disorders or any underlying respiratory or cardiac conditions such as ischemic heart disease, uncontrolled hypertension, recent chest, or abdominal surgery were excluded from the study.

Randomization

After screening eligible participants completed the informed consent and those selected were assigned into two groups based on simple random sampling. The assessor generated the random allocation sequence, enrolled and assigned participants to interventions. All the outcome measures were standardized and performed each time in use. The participants were blinded.

All the patients after meeting the inclusion criteria were randomly divided into two groups (Group A = 20 Participants and Group B = 20 Participants).

Interventions

Hold-relax proprioceptive neuromuscular facilitation pectoral stretching

The subjects had received a total of 7 sessions, i.e., on every alternate day with a duration of 20–25 min per session. Group A received hold relax PNF pectoral stretching [Figure 1]. Here, the subject was seated on a chair with hands behind the occiput and was asked to contract the pectorals in the direction of glenohumeral horizontal flexion in the maintained position. Isometric contraction meeting 50%–60% resistance of the therapist was performed.^[7]

Figure 1: PNF pectoral stretching given to patient in sitting position. PNF: proprioceptive neuromuscular facilitation

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Chest mobility exercises

Group B received chest mobility exercises which included rib rotation, passive lateral flexion in side lying, and trunk rotation in sitting with 7 sessions on every alternate day with a duration of 20–25 min per session [Figure 2], [Figure 3], [Figure 4].

Figure 2: Rib rotation

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Figure 3: Passive lateral flexion in side lying

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Figure 4: Trunk rotation in sitting

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Outcomes

Three outcome measures: (1) pulmonary function which included FEV1, FVC, FEV1/FVC were assessed using standardized electronic desktop spirometer, (2) fatigue using Fatigue severity scale which is 9-item questionnaire and scored on a 7-point scale, and (3) chest expansion assessed by an inch tape.

Statistical analysis

The data analysis within and between the groups was carried out using the software MedCalc. The normality of the data was calculated by applying the Shapiro Francia considering the P < 0.05 as normally distributed. The normally distributed values were further calculated for pre and postcomparison within groups using paired t and Wilcoxon test. Furthermore, the analysis between groups was calculated using unpaired t-test and Mann–Whitney sum rank test. Mean and standard deviation (SD) were calculated for pretreatment and posttreatment for each intervention group. Significance was set as P < 0.05 at 95% confidence interval.

Results

Baseline characteristics

In this study, 40 participants were included in the age group of 18–40 years. The mean age ± SD of the subjects was 26.5 ± 7 years.

Effect of intervention

With in-group analysis

After the seventh session of intervention after comparing all the scores with preintervention by using paired t-test, the result showed that in Group A participants, parameters of pulmonary function such as FEV1, FVC, and FEV1/FVC were improved (P < 0.0001, 0.0005, and 0.0092) which was statistically significant. Fatigue was decreased (P = 0.7422) but it was statistically not significant and chest expansion was improved (P < 0.0001) statistically significant.

Similarly, in Group B participants, there was an improvement in FEV1 value (P < 0.0955) that was statistically significant but the parameters of pulmonary function such as FVC and FEV1/FVC were improved (P = 0.2101 and P = 0.1297) but statistically not significant, fatigue was decreased (P = 0.0039) which was statistically significant and chest expansion was improved (P < 0.0001) which was also statistically significant [Table 1] and [Graph 1], [Graph 2], [Graph 3], [Graph 4], [Graph 5], [Graph 6], [Graph 7], [Graph 8].

Table 1: The difference between pre- and post- mean and standard deviation of Group A and Group B after 7 sessions of intervention using paired t-test

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Between group analysis

After comparison of the mean of postintervention score values between both the groups using unpaired t-test, it was observed that more improvements were seen in the scores of Group A participants in all outcome parameters, i.e., pulmonary function, fatigue, and chest expansion with P value (P < 0.05) which proved to be statistically significant [Table 2].

Table 2: Comparison of postintervention mean for pulmonary function test parameters (forced expiratory volume in the 1 s, forced vital capacity, forced expiratory volume in the 1 s/forced vital capacity), fatigue and chest expansion between Group A and Group B after 7 sessions of intervention using unpaired t-test

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Discussion

This study compared the effect of hold-relax PNF pectoral stretching and chest mobility exercises on pulmonary functions, fatigue, and chest expansion in subjects with COVID-19 survivors, of the age group of 18–40 years.

In the present study, our results showed that PNF pectoral stretching and chest mobility exercises had a significant effect on the pulmonary function, fatigue and chest expansion pre- and post-intervention in Groups A and B. There were no significant differences in FEV1/FVC parameter; but the other pulmonary parameters, i.e., FEV1 and FVC were statistically significant between the groups. Also between-group analysis of chest expansion showed that it was statistically significant. Moreover, between group analysis showed a significant statistical difference in few parameters of pulmonary function testing and chest expansion in Group A than Group B.

This shows that both the techniques were effective in improving pulmonary function, reducing fatigue, and improving chest expansion in the tested subjects for both the groups.

A study by Virendra Meshram K in 2016,^[8] an experimental study showed that there was a significant improvement on chest expansion by PNF pectoral stretching in elderly subjects with a pretest mean value of 0.28 and a posttest mean value of 0.46 at axilla level after a week with a P < 0.0001.

Studies^[9],[10] have shown that PNF stretching to the respiratory muscles with aerobic training, overall decreased dyspnea and improved some pulmonary parameters of chronic obstructive pulmonary disease (COPD) patients after 6 weeks of training within PNF group when comparing the mean value of pulmonary function pre and post showed significant difference. When comparing the PNF stretching and PNF stretching with aerobic training, the results showed that there is a significant difference with a P < 0.05.

Moreover, there are limited studies that state fatigue is decreased by PNF stretching.

A study of Katke et al.^[11] showed that chest wall stretching improved the pulmonary parameters more than the fatigue which further reduced the acute effects of respiratory fatigue in Marathon runners in comparison to conventional lower limb stretching. Another study conducted by Apoorva Bhatnagar, et al. in 2022 showed that PNF technique improved the pulmonary parameters and chest expansion in male smokers. Chest expansion measurement at axillary level improved by 6%, 10.1% at nipple level and by 10.5% at the xiphisternal level.^[12]

This study is the first one to find the effect of hold-relax PNF stretching on chest expansion, fatigue, and pulmonary function in the present study, the mean and SD of prepulmonary parameters that is FEV1, FVC and FEV1/FVC of group A was 2.0455 ± 0.6188, 2.1640 ± 0.6679, and 94.9505 ± 5.5137 which improved to 2.3915 ± 0.5704, 2.5190 ± 0.6203, and 97.1370 ± 3.6060 and that of group B the pre mean and SD were 44.2000 ± 4.3359 which improved to 43.7500 ± 4.2658 at the end of 7 sessions. The P value postintervention was 0.0255, 0.2101, and 0.1297 for FEV1, FVC, and FEV1/FVC, respectively.

In addition, the mean and SD of pre Fatigue score of group A was 46.5000 ± 12.0460 which improved to 43.5000 ± 7.1912 and that of Group B, the pre mean and SD was 46.5000 ± 12.0460 which improved to 43.5000 ± 7.1912 at the end of 7 sessions. The P value postintervention was 0.7422 for fatigue which is statistically not significant but clinically significant.

Moreover, the mean and SD of pre chest expansion measurements of Group A was 2.0000 ± 0.6689, which improved to 3.7750 ± 0.4723 and that of Group B the pre mean and SD were 2.3000 ± 0.6366 which improved to 3.3250 ± 0.6340 at the end of 7 sessions. The P value postintervention was P < 0.0001 for chest expansion which is highly significant.

One important finding of this study was a significant improvement in chest expansion and some parameters of pulmonary function in both the groups pre and post and also, the positive changes seen in the Group A was superior to that of the Group B.

As the individuals affected with COVID-19 reported symptoms as that of COPD, PNF stretching is thought to be an effective stretching method. Studies in the COPD population with PNF stretching as a maneuver have shown positive results on chest mobility, dyspnea, and pulmonary functions. Therefore, the possible physiology could be that PNF increases the respiratory muscle function and increases chest wall mobility by providing proprioceptive stimulus. In addition, the study by Michael T Putt et al.^[13] provides evidence that the hold relax PNF stretching techniques act on the restrictive component of COPD, improve the range of pectoralis major and also bring a change on the postural changes accompanied in COPD.

Chest mobility exercises improve the mobility, flexibility and also help in increasing compliance. Improved chest/thoracic mobility allows the subject to breathe with more efficiency with fuller lungs and improved ventilation. The chest mobility exercises also bring about a change in the biomechanics of respiration by facilitating active contraction of respiratory muscles.^[14] The focus of this technique remains to increase the range, the movement in all directions, and improvement in the respiratory function.

Therefore, the present research can be attributed to that chest mobilization exercises improve chest mobility and expansion as it aims to reduce stiffness of the chest wall due to any pathology. Therefore, this effect can further improve the biomechanics and also increase one's lung volume and hence, improvement in the pulmonary parameters can be noted.

The results of this study suggest that hold-relax PNF stretching was an effective treatment method to improve chest expansion and pulmonary function in COVID-19 affected individuals.

Study limitations

The study was done for a relatively small sample group of participants. COVID-19 survivors falling under severe impairment category according to the evidence-based consensus was not included in the study. Long-term follow-up of the subjects was not done.

Conclusions

The hold-relax PNF technique was more effective than chest mobility exercises for improving pulmonary function, reduce fatigue, and improve chest expansion.

Acknowledgment

We would like to thank the institution for allowing us to conduct the study, allowing to issue the PFT device and the participants who were enrolled in our study.

Financial support and sponsorship

This study was supported by institution and department who allowed and supported throughout to conduct the study.

Conflicts of interest

There are no conflicts of interest.

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