|Year : 2014 | Volume
| Issue : 2 | Page : 18-20
Role of exercise testing in assessment of cardiovascular system function in Zarda users
Amrith Pakkala1, Chitradurga Palaiah Ganashree2, Thippeswamy Raghavendra3
1 Department of Physiology, PES Institute of Medical Sciences and Research, Kuppam, Chittoor, Andhra Pradesh, India
2 Department of Physiology, Basaveshwara Medical College, Chitradurga, Karnataka, India
3 Department of Anesthesiology, Basaveshwara Medical College, Chitradurga, Karnataka, India
|Date of Web Publication
Department of Physiology, PES Institute of Medical Sciences and Research, Kuppam, Chittoor Dist., Andhra Pradesh
Source of Support: None, Conflict of Interest: None
Background: Zarda is a widely used form of smokeless tobacco in India. Cigarette smoking has extensive effects on cardiovascular functions. Zarda is prepared by a user by mixing tobacco with lime in palm and gives the user the choice to change the combination. This study aims to determine the effect of Zarda on cardiovascular system adaptability to exercise. There are conflicting opinions about the degree of adaptability of the cardiovascular system in delivering the physiological needs in case of severe exercise. A role of the normal cardiovascular system in delivering oxygen to meet the demands of various degrees of exercise has been a topic of considerable debate. The effect of Zarda usage on this phenomenon is studied here. Materials and Methods: Cardiovascular functions were assessed after maximal exercise testing by recording parameters like maximum heart rate, delta heart rate, recovery heart rate and maximum oxygen pulse in two groups, namely Zarda users and non-user controls. Results: On studying the differences in cardiovascular functions in users and controls, there was a significant difference found in maximum heart rate. The other parameters like delta heart rate and maximum oxygen pulse were on the higher side in controls while the recovery heart rate was significantly lower in the control group which was consistently maintained after exercise testing. Based on these findings it is suggested that there is a higher adaptability of the cardiovascular system to the exercise stimulus in the form of better VO 2 max, faster recovery of the exercise heart rate, and a lesser risk for cardiovascular mortality as suggested by the higher delta heart rate in non-Zarda users.
Keywords: Cardiovascular, exercise testing, Zarda
|How to cite this article:
Pakkala A, Ganashree CP, Raghavendra T. Role of exercise testing in assessment of cardiovascular system function in Zarda users. Sifa Med J 2014;1:18-20
|How to cite this URL:
Pakkala A, Ganashree CP, Raghavendra T. Role of exercise testing in assessment of cardiovascular system function in Zarda users. Sifa Med J [serial online] 2014 [cited 2024 Feb 24];1:18-20. Available from: https://www.imjsu.org/text.asp?2014/1/2/18/132963
Zarda is a widely used form of smokeless tobacco in India.  Cigarette smoking has extensive effects on cardiovascular functions.  Zarda is tobacco mixed with lime in the palm of a user and gives the user choice of mixing in different proportions. Use of smokeless tobacco is on the rise due to a presumably perceived view that it is relatively harmless.
On considering the various available opinions about the degree of adaptability of the cardiovascular system in delivering the physiological needs in case of severe exercise, it is difficult to understand the most limiting factor in the delivery of oxygen to the muscles during maximal muscle aerobic metabolism.  Some consider the pulmonary system as the most limiting factor whereas others hold this opinion of the cardiovascular system.
Mechanical constraints on exercise hyperpnoea have been studied as a factor limiting performance in endurance athletes'.  Others have considered the absence of structural adaptability to physical training as one of the "weaknesses" inherent in the healthy pulmonary system response to exercise. 
Ventilatory functions are an important part of functional diagnostics, , aiding selection and optimization of training and early diagnosis of sports pathology. Assessment of exercise response of dynamic lung functions in the healthy pulmonary system in the trained and the untrained has a role in clearing gaps in the above areas. Similarly, the assessment of cardiovascular functions by maximal exercise testing is useful in bringing out the adaptability of this system to the exercise stimulus.
| Materials and Methods
The present study was conducted in the department of physiology, PES Medical College, Kuppam, after obtaining ethical clearance as a part of cardio-pulmonary efficiency studies on two groups of non-Zarda user control group (n = 30) and Zarda users (n = 30) comparable in age and sex.
Informed consent was obtained and clinical examination to rule out any underlying disease was done. Healthy young adult males between 19 and 25 years who regularly use Zarda for at least past 3 years were considered in the user group whereas the non-user group did not have any such habit. Smoking, clinical evidence of anemia, obesity, involvement of cardio-respiratory system was considered as exclusion criteria.
A detailed procedure of sub-maximal and maximal exercise treadmill test was explained to the subjects and informed consent was obtained.
After sub-maximal exercise VO 2 max was assessed indirectly by using Astrand's nomogram.
The subjects were afterwards made to undergo maximal exercise testing. Maximal heart rate was determined by electrocardiogram (ECG). The delta heart rate was the difference between the maximal heart rate and the resting heart rate. The recovery heart rate was recorded after a period of 1 minute from the cessation of maximal exercise. Lead II is selected in the ECG machine and ECG is recorded for 15 seconds.
Recovery heart rate is obtained by using the formula,
Recovery HR = 15 - sec HR × 4
Maximum oxygen pulse was calculated by using the formula,
All these set of recordings were done on both the study and the control groups.
Statistical analysis was done using the unpaired Student t-test. A P-value < 0.05 was considered significant.
It is clear from [Table 1] that there is no difference in the anthropometric values between the two groups. Non-users had a significantly higher VO 2 max as compared to Zarda users.
|Table 1: A comparison of anthropometric data and VO2 max of non-Zarda users and Zarda users with statistical analysis
Click here to view
On comparing the cardiovascular efficiency parameters, it was observed from [Table 2] that the resting heart rate and recovery heart rate was higher in Zarda users, whereas non-users had significantly higher delta heart rate and maximum oxygen pulse. The maximum heart rate was numerically higher in non-users but it was not statistically significant.
|Table 2: A comparison of cardiovascular effi ciency parameters of Zarda users and non-users with statistical analysis
Click here to view
Considerable information can be obtained by studying the exercise response of cardio-vascular functions in Zarda users and non-users.
On comparing the anthropometric data of the two study groups it is clear that the age and sex matched subjects have no statistically significant difference in height, weight and BMI taking a P- value of <0.01 as significant.
VO 2 max values were higher in non-users and were statistically significant (P < 0.001). This observation is expected in view of the deleterious effect of nicotine in Zarda. VO 2 max is an objective index of the functional capacity of the body's ability to generate power.
The higher resting heart rate is attributable to the lower vagal tone in users and supports the hypothesis that nicotine training modifies heart rate control through neurocardiac mechanisms primarily by shifting the autonomic balance toward sympathetic dominance.
There is no significant difference in the maximal heart rate between the two groups.
The higher delta heart rate in non-users suggests that this group is at a lesser risk for cardiovascular mortality.
The faster recovery in non-users is due to the better vagal tone in this group. Maximum oxygen pulse is an index representing both stroke volume and average A-V oxygen difference; a higher value in non-users suggests that exercise increases both stroke volume and average A-V oxygen difference much more in this group.
|Gupta PC. The public health impact of tobacco. Curr Sci 2001;81:475-81.
|WHO: World tobacco epidemic. 2 nd edn. Geneva: WHO publications. 1993. p. 47.
|Guyton AC, Hall JE, editors. Text book of medical physiology. 11 th ed. United States: Saunders; 2006. p. 1061-2.
|Johnson BD, Saupe KW, Dempsey JA. Mechanical constraints on exercise hypernea in endurance athletes. J Appl Physiol 1992;73:874-86.
|Dempsey JA, Johnson BD, Saupe KW. Adaptations and limitations in the pulmonary system during exercise. Chest 1990;97(3 Suppl):81s-7.
|Andziulis A, Gocentas A, Jascaniniene N, Jaszczanin J, Juozulynas A, Radzijewska M. Respiratory function dynamics in individuals with increased motor activity during standard exercise testing. Fiziol Zh 2005;51:80-95.
|Seaton A, Seaton D, Leitch AG, editors-Crofton and Douglas's respiratory diseases. 5 th ed. Oxford: Oxford University press; 2000. p. 43-5.
[Table 1], [Table 2]