Home | About us | Editorial Board | Search | Ahead of print | Current Issue | Archives | Instructions | Online submissionContact Us   |  Subscribe   |  Advertise   |  Login  Page layout
Wide layoutNarrow layoutFull screen layout
Lung India Official publication of Indian Chest Society  
  Users Online: 297   Home Print this page  Email this page Small font size Default font size Increase font size


 
  Table of Contents    
ORIGINAL ARTICLE
Year : 2011  |  Volume : 28  |  Issue : 3  |  Page : 169-173  

Effects of upper body resistance training on pulmonary functions in sedentary male smokers


1 Department of physiotherapy, Sikkim Manipal Institute of Medical Sciences,Gangtok, India
2 D M Patel College of Physiotherapy, Amreli, Gujrat, India
3 Srinivas College of Physiotherapy, Mangalore, India

Date of Web Publication19-Aug-2011

Correspondence Address:
V P Singh
Assistant Professor, Sikkim Manipal Institute of Medical Sciences, 5th Mile Tadong, Gangtok-737102
India
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/0970-2113.83971

Rights and Permissions
   Abstract 

Background: Cigarette smoking is well correlated with lung diseases such as chronic obstructive pulmonary disease. It is common among men than women in India. In addition, sedentary lifestyle is associated with less efficient pulmonary function. Effectiveness of upper body resistance training (UBRT) in improving pulmonary function is unclear. Keeping all these factors in view, this study aims to examine the effect of UBRT on pulmonary function in male sedentary smokers. Materials and Methods: This study recruited 36 sedentary male smokers, of which 30 were randomized into two groups after fulfilling eligibility criteria-an exercising experimental group (EG) (N=15) or non-exercising control group (CG) (N=15). The EG group were assigned to exercise for 4 weeks, 3 times weekly on non-consecutive days using UBRT program and breathing exercise. In the CG, only breathing exercise was given for 10 min. Both groups were equivalent in baseline characteristics. Results: The improvement in forced expiratory volume in one second (FEV 1 ) and FEV 1 /forced vital capacity (FVC) values were seen significant in EG after 4 weeks of UBRT: from 3.62±0.56 to 3.96±0.51 (P=0.000) and 0.88±0.11 to 0.96±0.13 (P<0.001), respectively. But FVC did not show significant change in the EG (P=0.430). There were no significant changes in FEV 1 , FVC, and FEV 1 /FVC values in CG after 4 weeks of intervention. On inter-group comparison, significant difference was found between CG and EG for FEV 1 and FEV 1 /FVC values. Conclusion: Four weeks of UBRT program brought about significant changes in the pulmonary function in male sedentary smokers.

Keywords: Pulmonary function, resistance training, smokers, upper body exercise


How to cite this article:
Singh V P, Jani H, John V, Singh P, Joseley T. Effects of upper body resistance training on pulmonary functions in sedentary male smokers. Lung India 2011;28:169-73

How to cite this URL:
Singh V P, Jani H, John V, Singh P, Joseley T. Effects of upper body resistance training on pulmonary functions in sedentary male smokers. Lung India [serial online] 2011 [cited 2019 Dec 10];28:169-73. Available from: http://www.lungindia.com/text.asp?2011/28/3/169/83971


   Introduction Top


Cigarette smoking has been clearly documented as a primary cause of impaired pulmonary function. [1],[2] It is known to cause cardiovascular and cerebrovascular disorders, chronic obstructive pulmonary diseases (COPD), and cancers. [3] It is believed that smoking, either active or passive, has negative influence on lung function, especially forced expiratory volume in one second (FEV 1 ), forced vital capacity (FVC), FEV 1 /FVC, and diffusing capacity for carbon monoxide (DLCo), with simultaneous increase in forced residual capacity value. [4],[5],[6] It has been shown that being sedentary and smoking were related to lower Maximal Treadmill Test (MTT), FEV 1 , FVC, and FEV 1 /FVC ratio in both men and women. [7] It has been found that muscular exercise increases O 2 consumption, rate of diffusion, and the rate and depth of respiration, which lead to improvement in FVC. [8] Moreover, it has been shown that moderate-to-high levels of regular physical activity are associated with a lower lung function decline and risk of COPD in active smokers. [9] The most recent guidelines on pulmonary rehabilitation (PR) recommends the inclusion of exercise training targeted at the muscles of the upper extremities (UEs) in physical therapy programs specific to subjects with COPD. [10] The rationale supporting the inclusion of UE exercise training (UEET) in pulmonary rehabilitation for subjects with COPD is the competitive dual role of a number of UE muscles that sustain the upper girdle, but also act as accessory respiratory muscles, which work more during physical effort and even at rest in a subject who has COPD with diaphragmatic dysfunction. Thus, during activities involving the UEs, respiration becomes ineffective because the accessory respiratory muscles work to sustain the shoulder girdle, which may contribute to producing early fatigue and dyspnea. [11] In addition, there is a shift in respiratory work to the diaphragm. This is associated with thoracoabdominal dyssynchrony, severe dyspnea, and termination of exercise at low workloads, especially in subjects with more severe bronchial obstruction. Upper limb exercise training for subjects with COPD has been shown to increase upper limb work capacity, improve endurance, and reduce O 2 consumption at a given workload. [12] It is attributed that that reduction in FEV 1 in subjects with COPD is characterized by thoracoabdominal dyssynchrony of the muscles of inspiration, severe dyspnea, and overall Unsupported Arm Exercise (UAE) intolerance. [13] Arm training can help improve synchronization and coordination, resulting in a decreased minute ventilation. [14] The biological mechanism in which both physical activity and smoking interact antagonistically is an exaggerated inflammatory response in the lungs. Inflammation relates smoking with lung function decline and pathogenesis of COPD. Regular physical activity suppresses the production of inflammatory markers such as Interleukin-6 (IL-6), Tumor Necrosis Factor-Alpha (TNF-a), and C-Reactive Protein (CRP). [9] In addition to UBRT, breathing exercises are capable of increasing the pulmonary ventilation and improving mobilization of the chest wall, drainage of trachea bronchial secretions, promote relaxation, which contributed to a significant increase in vital capacity (VC), FEV 1 , peak expiratory flow (PEF), and maximal voluntary ventilation (MVV). [8] Another study has emphasized that by giving short-term high-intensity strength training, pulmonary function might improve. [15] Present literature demands additional research to clarify the effects of UBRT on pulmonary function. Therefore, this study aims to evaluate the efficacy of UBRT on pulmonary function so that more appropriate choices can be made when designing exercise programs for individuals with decreased pulmonary function and to assist in maintenance of normal pulmonary function, particularly in smokers.


   Materials and Methods Top


This experimental study recruited 36 subjects from the general population in Mangalore community who responded to a local advertisement and volunteered. Six patients were excluded from the study because four did not meet inclusion criteria and two refused to participate. [Figure 1] presents the recruitment and allocation of subjects in two groups and [Table 1] presents baseline characteristics of subjects. Inclusion criteria consisted of male subjects in the age group of 25-55 years who reported having smoked a minimum of 10 cigarettes/day for at least 10 years and still use cigarettes. [16] They must have sedentary lifestyle, as in no leisure-time physical activity or activities done for less than 20 minutes or fewer than three times per week. [17] Exclusion criteria were as follows: Incapable of realizing the protocol of respiratory exercises, difficulty in completing the evaluation of pulmonary function, [16] and any known pulmonary, cardiac pathologies, musculoskeletal disorders, or recent surgery. Detailed information about general health, physical activity, and smoking status were self-reported by the subjects in the pre-exercise questionnaire. We had randomly assigned these 30 subjects into two groups: experimental group (EG) (n=15) who underwent 4 weeks of UBRT program and deep breathing exercise, and the control group (CG) (n=15) who underwent only breathing exercise by a simple random table method. The subjects were further provided with an explanation of the risks, benefits, and procedures of the study, along with the subjects being shown the correct technique for each exercise. After all these aspects were discussed, a written consent was obtained for voluntary participation in our study. [Table 1] represents the statistical analysis of the subject characteristics based on age, height, weight, and pulmonary functions in chronic smokers. There was no statistical difference between the two groups at baseline.
Table 1: Baseline characteristics of subjects

Click here to view
Figure 1: Flow chart of subjects, intervention, and analysis

Click here to view


The 4-week training program included 30 minutes of UBRT that was supplemented with 10 minutes of deep breathing exercises for the EG as well as for CG.

The EG subjects were under the direct supervision of a physiotherapist during the training sessions. At each training session, recordings were made of the exercises performed, the weight used, and the number of sets and repetitions completed for each exercise. Ten minutes of warm-up period was given, which includes general body active exercises and upper extremity muscle stretching. The strength training program included five major muscle groups, which were performed with the following weight-lifting procedures: (1) a seated chest press (mainly for strengthening of the pectoralis major muscle); (2) frontal latissimus dorsi pull-downs (mainly for the latissimus dorsi); (3) seated rows (mainly for biceps, deltoid, and triceps); (4) seated shoulder press (mainly for triceps, deltoid, and pectoralis muscles); and (5) barbell shoulder shrugs (mainly for trepazius). Upper body strength was assessed using one repetition maximum (1RM) method, which was considered the maximum weight that could be lifted through the full range of motion one time.

At beginning of first week, given resistance was 50% of 1RM and it progressively increased to 85% of 1RM during the final week of training. Each exercise was performed as 3 sets of 10 repetitions each. Thereafter, the training workload was increased when more than 10 repetitions per set could be performed. This protocol was repeated for three non-consecutive days of UBRT per week for four weeks. One minute rest period was given between each set and 30 seconds between each exercise. At the end of each session, cool down exercises were given for 10 mins, which also included general body active exercises and upper extremity muscle stretching.

The conventional breathing exercise was given to CG for 10 min and subjects were instructed to maintain their usual activities and not to participate in any form of exercise during the four-week training period. This protocol was also repeated for three non-consecutive days per week for four weeks.

The outcome measures used in this study are pulmonary function measures FVC, FEV 1, and the FEV 1 /FVC ratio. Pulmonary functions were measured using computerized spirometer (Spirolyser SPL-10). The spirometry values of all subjects were evaluated before and after the four weeks experimental period. Pulmonary functions were assessed using standard spirometry guidelines given by ATS/ERS. [18] Subjects in both groups were asked to abstain from smoking for at least 4 hours before both the pre-intervention test and post-intervention spirometry measurement procedure.


   Ethics Top


Ethical clearance was obtained from institutional ethics committee.


   Statistics Top


Statistical analysis was performed using SPSS 16.0. For each group, pre- and post-training comparisons were made using paired t test and comparisons were made between the control and EG, by using Mann-Whitney U test. A value of P<0.05 was considered statistically significant.


   Results Top


There was no drop out from our study. All subjects completed four weeks of the UBRT program and the CG underwent only breathing exercise program.

In the EG, there was statistically significant improvement in FEV 1 and FEV 1 / FVC values after four weeks of training from 3.62±0.56 to 3.96±0.51 and 0.88±0.11 to 0.96±0.13 (P=0.001), respectively. But there was no statistically significant improvement in FVC value from 4.11±0.64 to 4.13±0.64 (P>0.05) as shown in [Table 2].
Table 2: Paired t test analysis of mean FEV1, FVC, and FEV1/FVC in the experimental group pre- and post-intervention

Click here to view


In the CG, there was no statistically significant difference in FEV 1 from 3.54±0.47 to 3.49±0.51, FVC from 4.16±0.47 to 4.15±0.48, and FEV 1 /FVC from 0.84±0.096 to 0.84±0.11 values after four weeks of breathing exercise program (P>0.05), as shown in [Table 3].
Table 3: Paired t test analysis of mean FEV1, FVC, and FEV1/FVC in the control group pre- and post-intervention

Click here to view


On inter-group comparison, significant difference was noted between the control and experimental groups for FEV 1 and FEV 1 /FVC values. FEV 1 value in the experimental group was 0.351±0.21 and in the CG it was -0.04±0.13 (P=0.000); FEV 1 /FVC values in the experimental group was 0.08±0.07 and in the CG it was 5.4±20.9 (P=0.419). However, there was no significant change in FVC value, as shown in [Table 4].
Table 4: Mann-whitney U test analysis of FEV1, FVC, and FEV1/FVC for comparison between groups

Click here to view



   Discussion Top


This study sought to evaluate whether UBRT is useful in addition to conventional breathing exercise in male smokers with sedentary lifestyle. We found that the combination of UBRT and conventional breathing exercise was safe and well tolerated despite the chronic smoking pattern and was associated with statistically significant improvement in FEV 1. However, our study did not show statistically significant change in the FVC value. Our study has shown similar findings with the previous study, which demonstrated increase in spirometric values in welders after 2 months of arm training, breathing exercise, and incentive spirometry. Authors have attributed the findings to improvement in rate and depth of respiration, consumption of O 2 , and rate of diffusion due to muscular exercise. They have also stated that breathing exercise promotes a more efficient breathing pattern, improvement in ventilation, mobilization of the chest wall, drainage of trachea bronchial secretions, as well as promotes relaxation. [8] Another study found improvement in spirometry values in women with breast cancer, which has been attributed to exercise that appeared to maintain erythrocyte concentrations during treatment, but still the mechanisms by which exercise training benefits breast cancer survivors during or after treatment remain elusive. [19] However, in contrast to above studies, a randomized control study has demonstrated decrease in FEV 1 value in severe COPD subjects after resistance training and aerobic training interventions. They have given the probable reason as fatigue due to resistance training session and their medical treatment. [20]

In a previous study, 8 weeks of upper body exercises did not show a statistically significant improvement in the FEV 1 /FVC ratio. [21] This finding is in contrast with the present investigation, which shows significant increase in the FEV 1 /FVC ratio. This significant increase in the current study was possibly due to the increase in FEV 1 and non-significant change in FVC.

A previous study has demonstrated that FVC value significantly increased after 8 weeks of upper body gravity resistance exercises and proprioceptive neuromuscular facilitation training. [21] A study supporting the above statement found statistically significant improvement in FVC, with unchanged FEV 1 values. They attributed this improvement in the FVC value to improvement in functional capacity. [22] A probable explanation for the increase in FVC in previous studies was that, when exercising the pectoralis major muscle against progressive loads, it can result in a 20% increase in the FVC value of the subjects. [23] Our study shows lesser change in FVC as compared to FEV 1 , which needs further evaluation. However, the changes in the FVC are not statistically significant but are clinically relevant. Larger changes in the FVC value in previous studies [21],[22] can be due to longer duration of exercise training.

There is statistically significant difference between control and experimental group for FEV 1 and FEV 1 /FVC values. Some previous studies [24],[25],[26],[27] showed no significant change in these parameters; these may be due to inclusion of different population like severe COPD, older age group (>60 yrs), inadequate sample size, and level of training stimulus. The improvement in pulmonary functions in our study may be due to inclusion of asymptomatic male sedentary chronic smokers aged 25-55 years. Besides, our study differs from other studies in the methodological aspect, as we administered both UBRT and conventional breathing exercise to the EG and only conventional breathing exercise was performed on CG. High-intensity UBRT (50-85% of 1RM) was administered for 4 weeks for non-consecutive days. Thus, due to a combined effect, there may be an improvement in synchronization, coordination, and true metabolic adaptations in the inspiration muscles, which results in decreased minute ventilation and reduction in FRC, which may improve pulmonary function parameters. The present investigation attempted to develop an inexpensive and simple resistance training program as a tool to improve or maintain the pulmonary function of smokers and/or individuals prone to developing pulmonary pathologies. Therefore, the aim of the investigation was to develop a primary preventive strategy to help prevent smokers from developing pulmonary diseases. In doing so, it may provide clinicians, patients and healthy (and possibly pathological) individuals with an additional or improved mode of exercise (over and above the traditional aerobic modes) to improve pulmonary function, health status, and a sense of well-being.


   Conclusion Top


Four weeks of high-intensity upper body resistance training with an adjunct in the form of conventional breathing exercise have an important beneficial impact on pulmonary function parameters, especially FEV1 and FEV 1 /FVC values in male sedentary smokers.

 
   References Top

1.Gold Workshop Report. Global Strategy for the Diagnosis, Management, and Prevention of Chronic Obstructive Pulmonary Disease, Available from: http://www.gold.copd.org (2005) [Last cited on 2009, Jan 7].  Back to cited text no. 1
    
2.Smoller JW, Pollack MH, Otto MW, Rosenbaum JF, Kradin RL. Panic anxiety, dyspnea and respiratory disease: Theoretical and clinical considerations. Am J Respir Crit Care Med 1996;154:6-17.  Back to cited text no. 2
[PUBMED]  [FULLTEXT]  
3.Ozlu T, Bulbul Y. Smoking and lung cancer. Tuberk Toraks 2005;53:200-9.  Back to cited text no. 3
    
4.Kerstjens H, Rijcken B, Schouten P, Postma D. Decline of FEV 1 by age and smoking status: Facts, figures, and fallacies. Thorax 1997;52:820-7.  Back to cited text no. 4
    
5.Omori H, Nonami Y, Morimoto Y. Effect of smoking on FEV 1 decline in a cross sectional and longitudinal study of large cohort Japanese males. Respirology 2005;10:464-9.  Back to cited text no. 5
[PUBMED]  [FULLTEXT]  
6.Dugan D, Walker R, Monroe DA. The effects of 9-week program of aerobic and upper body exercise on the maximal voluntary ventilation of chronic obstructive pulmonary disease patients. J Cardiopulm Rehabil 1995;15:130-3.  Back to cited text no. 6
[PUBMED]    
7.Cheng YJ, Macera CA, Addy CL, Sy FS, Wieland D, Blair SN. Effects of physical activity on exercise tests and respiratory Function. Br J Sports Med 2003;37:521-8.  Back to cited text no. 7
[PUBMED]  [FULLTEXT]  
8.El-batanouny MM, M. Amin Abdou, Salem EY, El-Nahas HE. Effect of exercise on ventilatory function in welders. Egypt J Bronchol 2009;3:67-73.  Back to cited text no. 8
    
9.Judith Garcia-Aymerich, Peter Lange, Benet M, Schnohr P, Antó JM. Regular physical activity modifies smoking-related lung function decline and reduces risk of chronic obstructive pulmonary disease. A population-based cohort study. Am J Respir Crit Care Med 2007;175:458-63.  Back to cited text no. 9
    
10.Ries AL, Bauldoff GS, Carlin BW, Casaburi R, Emery CF, Mahler DA, et al. Pulmonary Rehabilitation, Joint ACCP/AACVPR Evidence-Based Clinical Practice Guidelines. Chest 2007;131:4S-42.  Back to cited text no. 10
[PUBMED]  [FULLTEXT]  
11.Costi S, Crisafulli E, Antoni FD, Beneventi C, Fabbri LM, Clini EM. Effects of unsupported upper extremity exercise training in patients with COPD. Chest 2009;136:387-95.  Back to cited text no. 11
[PUBMED]  [FULLTEXT]  
12.Holland AE, Hill CJ, Nehez E, Ntoumenopoulos G. Does unsupported upper limb exercise training improve symptoms and quality of life for patients with chronic obstructive pulmonary disease? J Cardiopulm Rehabil 2004;24:422-7.  Back to cited text no. 12
[PUBMED]  [FULLTEXT]  
13.Celli BR, Criner G, Rassulo J. Ventilatory muscle recruitment during unsupported arm exercise in normal subjects. J Appl Physiol 1988;64:1936-41.  Back to cited text no. 13
    
14.Epstein SK, Celli BR, Martinez FJ, Couser JI, Roa J, Pollock M, et al. Arm training reduces the VO 2 and VE cost of unsupported arm exercise and elevation in chronic obstructive pulmonary disease. J Cardiopulm Rehabil 1997;17:171-7.  Back to cited text no. 14
[PUBMED]  [FULLTEXT]  
15.Wright PR, Heck H, Langenkamp H, Franz KH, Weber U. Influence of resistance training on pulmonary function and performance measures of patients with COPD. Pneumologie 2002;56:413-7.  Back to cited text no. 15
[PUBMED]  [FULLTEXT]  
16.Galvan CC, Cataneo AJ. Effect of respiratory muscle training on pulmonary function in preoperative preparation of tobacco smokers. Acta Cir Bras 2007;22:112-8.   Back to cited text no. 16
    
17.Prakash S, Meshram S, Ramtekkar U. Athletes, yogis and individuals with sedentary lifestyles; do their lung functions differ? Indian J Physiol Pharmacol 2007;51:76-80.  Back to cited text no. 17
[PUBMED]    
18.Celli BR, Macnee W. committee members of the ATS/ERS Task force. Standards for the diagnosis and treatment of patients with COPD: A summary of the ATS/ERS position paper. Eur Respir J 2004;23:932-46.  Back to cited text no. 18
    
19.Schneider CM, Hsieh CC, Sprod LK, Carter SD, Hayward R. Effects of supervised exercise training on cardiopulmonary function and fatigue in breast cancer survivors during and after treatment. Cancer 2007;110:918-25.  Back to cited text no. 19
[PUBMED]  [FULLTEXT]  
20.Panton LB, Golden J, Broeder CE, Browder KD, Cestaro-Seifer DJ, Seifer FD. The effects of resistance training on functional outcomes in patients with chronic obstructive pulmonary disease. Eur J Appl Physiol 2004;91:443-9.  Back to cited text no. 20
[PUBMED]  [FULLTEXT]  
21.Ries AL, Ellis B, Hawkins RW. Upper extremity exercise training in chronic obstructive pulmonary disease. Chest 1988;93:688-92.  Back to cited text no. 21
[PUBMED]    
22.Moorcroft AJ, Dodd ME, Morris J, Webb AK. Individualized unsupervised exercise training in adults with cystic fibrosis: A 1 year randomized controlled trial. Thorax 2004;59:1074-80.  Back to cited text no. 22
[PUBMED]  [FULLTEXT]  
23.Pulmonary Rehabilitation: Joint ACCP/AACVPR Evidence-Based Guidelines, ACCP/AACVPR Pulmonary Rehabilitation Guidelines panel. Chest 1997;112:1363-96.  Back to cited text no. 23
    
24.Lake FR, Henderson K, Briffa T, Openshaw J, Musk AW. Upper-limb and lower-limb exercise training in patients with chronic airflow obstruction. Chest 1990;97:1077-82.  Back to cited text no. 24
[PUBMED]  [FULLTEXT]  
25.Clark CJ, Cochrane LM, Mackay E, Paton B. Skeletal muscle strength and endurance in patients with mild COPD and the effects of weight training. Eur Respir J 2000;15:92-7.  Back to cited text no. 25
[PUBMED]  [FULLTEXT]  
26.O'Donnell DE, McGuire M, Samis L, Webb KA. General exercise training improves ventilatory and peripheral muscle strength and endurance in chronic airflow limitation. Am J Respir Crit Care Med 1998;157:1489-97.  Back to cited text no. 26
[PUBMED]  [FULLTEXT]  
27.Susheel Kumar Bindroo, Raj Kumar. Effect of home based pulmonary rehabilitation program on disability in patients with persistent bronchial asthma. Indian J Allergy Asthma Immunol 2004;18:63-71.0  Back to cited text no. 27
    


    Figures

  [Figure 1]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]


This article has been cited by
1 A laboratory-based evaluation of exercise plus contingency management for reducing cigarette smoking
Allison N. Kurti,Jesse Dallery
Drug and Alcohol Dependence. 2014;
[Pubmed] | [DOI]
2 Effectiveness of the physical activity promotion programme on the quality of life and the cardiopulmonary function for inactive people: Randomized controlled trial
Rocío Martín-Valero,Antonio Ignacio Cuesta-Vargas,María Teresa Labajos-Manzanares
BMC Public Health. 2013; 13(1): 127
[Pubmed] | [DOI]
3 Effectiveness of the physical activity promotion programme on the quality of life and the cardiopulmonary function for inactive people: Randomized controlled trial
Martín-Valero, R. and Cuesta-Vargas, A.I. and Labajos-Manzanares, M.T.
BMC Public Health. 2013; 13(1)
[Pubmed]
4 Exercise-based smoking cessation interventions among women
Linke, S.E. and Ciccolo, J.T. and Ussher, M. and Marcus, B.H.
Womenæs Health. 2013; 9(1): 69-84
[Pubmed]



 

Top
  
 
  Search
 
  
    Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
    Access Statistics
    Email Alert *
    Add to My List *
* Registration required (free)  

 
  In this article
    Abstract
   Introduction
    Materials and Me...
   Ethics
   Statistics
   Results
   Discussion
   Conclusion
    References
    Article Figures
    Article Tables

 Article Access Statistics
    Viewed2767    
    Printed81    
    Emailed1    
    PDF Downloaded663    
    Comments [Add]    
    Cited by others 4    

Recommend this journal