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ORIGINAL ARTICLE
Year : 2014  |  Volume : 14  |  Issue : 2  |  Page : 103-108

A study of physical fitness of trained individuals of an urban population in Pune


1 Department of Physiology, AD Instruments South Asia (India) Pvt Ltd, New Delhi, India
2 Department of Physiology, Burdwan Medical College Hospital, Burdwan, West Bengal, India
3 Department of Physiology, Mahatma Gandhi Institute of Medical Sciences, Wardha, Maharashtra, India

Date of Web Publication9-Oct-2014

Correspondence Address:
Arunima Chaudhuri
Krishnasayar South, Borehat, Burdwan - 713 102, West Bengal
India
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DOI: 10.4103/1319-6308.142357

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  Abstract 

Background: Physical exercise is the nature's panacea for preventing ill health. Objectives: To study the effects of regularized training programs in an urban population. Materials and Methods: This cross sectional pilot project was carried in a time span of 6 months on two study populations located at the Medical College and Physical training unit in Pune. Untrained Group comprised of 50 healthy young male students and Trained Group comprised of 50 physically trained young males. History was recorded followed by anthropometry and clinical examination. Body mass index (BMI) and Body surface area (BSA) were calculated. Resting pulse rate and blood pressure, resting respiratory rate, VO 2 Max, Physical fitness index (PFI), breath holding time (BHT), and 40 mm endurance test time were measured. Statistical analysis was done using SPSS software version 16. Results: There was no significant difference in age, and height between the two groups, while BMI, BSA, pulse rate, and respiratory rate were significantly lower in trained individuals. Physically untrained subjects had a VO 2 Max value of less than 55 ml/kg/min (range, 30 to 55 ml/kg/min), while all the physically trained subjects had VO 2 Max of more than 50 ml/kg/min (range, 50 to 80 ml/kg/min) (P < 0.0001). The mean PFI, BHT, and the mean 40 mm endurance time were significantly higher in trained subjects. Conclusion: Various cardio-respiratory and other fitness parameters are markedly better in youths who undertake couple of hours of exercise. This better cardio-respiratory fitness is known to translate into a lower cardiac disease risk in future.

  Abstract in Arabic 

دراسة اللياقة البدنية من الأفراد المدربين من سكان الحضر في بيون
خلفية الدراسة: ان ممارسة الرياضة البدنية هي بمثابة الوسيلة العلاجية الطبيعية لمنع اعتلال الصحة. وكانت ألأهداف من هذه الدراسة هى التقصى عن آثار برامج التدريب المنتظم في سكان الحضر
المواد والطرق: تم تنفيذ هذا الدراسة في فترة زمنية امتدت لست أشهر وعلى مجموعتين من طلاب كلية الطب ووحدة من الجيش في بيون. تتألف المجموعة الاولى من خمسين من الطلاب الذكورغير المدربين وتتألف المجموعة الثانية من خمسين من الذكور المدربين جسديا. وتم تسجيل تاريخهم الصحى ثم اجريت القياسات جسمية والفحص الطبى. وتم حساب مؤشر كتلة الجسم ((BMI ومساحة سطح الجسم (BSA) . وتم ايضا قياس معدل النبض اثنا الراحة وضغط الدم ومعدل التنفس VO2max ، مؤشر اللياقة البدنية (PFI)، وفترة توقف التنفس (BHT)، واختبار التحمل الوقتى. وقد تم التحليل الإحصائي باستخدام برنامج SPSS النسخة السادس عشر
النتائج: لم يكن هناك فرقا كبيرا في الطول بين المجموعتين، في حين أن مؤشر كتلة الجسم، ومعدل (BSA)، ومعدل النبض ومعدل التنفس كان أقل بكثير في الأفراد المدربين. اما غير المدربين جسديا كان لديهم معدل VO2max أقل من 55 مل / كغ / دقيقة (مجموعة، 30-55 مل / كغ / دقيقة)، في حين أن جميع المدربين جسديا فلديهم معدل VO2max أكثر من 50 مل / كغ / دقيقة (المدى ، 50 و 80 مل / كغ / دقيقة) <0.0001).
الخلاصة: هناك عدة مقاييس للقلب والجهاز التنفسي وغيرها من مؤشرات اللياقة البدنية هي أفضل بشكل ملحوظ في الشباب الذين يمارسون ساعتين من الرياضة. ومن المعروف أن المحافظة على لياقة الجهاز الدوري التنفسى ينتج عنه انخفاضا فى مخاطر الاصابة بأمراض القلب في المستقبل.

Keywords: Physical fitness index, physical training programs, VO 2 max


How to cite this article:
Gupta R, Chaudhuri A, Bansod N. A study of physical fitness of trained individuals of an urban population in Pune . Saudi J Sports Med 2014;14:103-8

How to cite this URL:
Gupta R, Chaudhuri A, Bansod N. A study of physical fitness of trained individuals of an urban population in Pune . Saudi J Sports Med [serial online] 2014 [cited 2019 Dec 11];14:103-8. Available from: http://www.sjosm.org/text.asp?2014/14/2/103/142357


  Introduction Top


With rapid urbanization, industrialization, and increasing level of affluence, the price that the society is paying is in the form of tremendous load of "non-communicable diseases." About 3.3% of all deaths can be attributed to physical inactivity. World-wide estimates as per a recent WHO report indicates that on a long-term, physical inactivity carries an increased risk of 1.05 to 2.63 times for IHD, 1.2 to 2.89 times for hypertension and stroke, 1.08 to 4.31 times for diabetes type II, 1.02 to 2.5 times for colonic cancer, 1.02 to as much as 5 times for breast cancer, and 1.02 to 1.37 times for osteoporosis. It is also estimated by the WHO that globally, over 1 billion adults are overweight and 3 million are obese. [1]

Physical exercise is the nature's panacea for preventing ill health. The following physiological adaptations are achieved with endurance training exercise: Increase in vagal tone, resting stroke volume, end-diastolic volume, maximal oxygen consumption (V0 2 Max) by 5 to 20%; change in muscle mass due to hypertrophy (increase in size) of muscle, and increase in production of contractile proteins, e.g. actin and myosin; change in the muscle fibers which lead to more oxygen extraction by the muscle and improve muscle fibers' ability to provide energy during prolonged exercise. [2],[3] Both high-resistant training and prolonged submaximal training programs stimulate an upregulation in Na + -K + ATPase concentration, but only the prolonged submaximal training program enhances the potential for beta-oxidation, oxidative phosphorylation, and glucose phosphorylation. [3],[4],[5]

There are various methods by which the level/state of physical training can be estimated. Cardiorespiratory fitness is one of the most important parameters of physical fitness and is assessed by cardiorespiratory efficiency tests. These tests include assessment of VO 2 Max, 40mm Hg Test, Breath Holding Test, etc., which are generally considered as field methods. Other methods use sophisticated instruments, e.g. bicycle ergometry, treadmill test.

VO 2 max has been found as one of the most applicable parameters that can measure the aerobic capacity of an individual. [3],[4],[5]

The present work was conducted to study the cardiorespiratory efficiency in physically trained young adult males who have been undergoing moderate type of physical exercise for past 1 to 2 years. In the army set up, physical training is given in a very organized and an effective way. That is why effectiveness of training program was studied in army personnel. Young males suffer more from cardiovascular diseases as compared to females of same age group. Estrogen is known to be a vagotonic and sympatholytic hormone. Hormonal factors do cause variance in Heart Rate Variability among males and females. [6] Hence, the study was conducted on young males.


  Materials and methods Top


Institutional Ethics Committee approval was obtained prior to commencement of this cross-sectional, analytic, descriptive pilot project. The study was conducted in a time span of 6 months on two study populations located at a Medical College and at an army unit in Pune.

Untrained group

This group comprised of 50 healthy male students of first M.B.B.S who are not engaged in any type of regular physical exercise.

Trained group

This group comprised of 50 physically trained young males from a training centre. These trainees had been undergoing various types of physical training/exercise every day for the past 1 to 2 years. The schedule of daily routine for physical training was on an average 5 days a week, with these details:

Morning:

10 minutes of warm-up followed by 2.5 to 5 km run.

Evening:

60 minutes of games, in which they play volleyball or basket ball.

Sampling was done using the multistage random sampling technique. The given training unit was divided into four units. Each unit was further divided into four groups. Each group had about 200 men. Each group was further sub divided into four subgroups. For the study purpose, one unit was randomly selected and further one group was randomly selected from the unit. A nominal roll of all the subgroups of this group was obtained. A total of 50 trained males between age group 17 and 22 years were randomly picked up from the list using the lottery system.

First year MBBS batch comprised of a total of 150 students which is further divided into 3 batches, i.e. A batch, B batch, and C batch. Of the total 150 students, 62 students were male students. A nominal roll of all the first year medical students was obtained. A total of 50 male students were randomly picked up from the list of students from the three batches.

Permission was obtained from the authorities of the training centre to conduct this study. Consent was obtained for the study from the subjects.

Inclusion criteria

Male subjects belonging to the age group 17 to 22 years were included.

Exclusion criteria

Subjects suffering from chronic debilitating diseases such as cardiac arrhythmias, hypertension, diabetes, ischemic heart disease, retinopathy, nephropathy, respiratory diseases; smokers; those with family history of metabolic diseases including diabetes and hypertension; persons receiving any drug that may affect the autonomic reflexes; and those on any daily exercise regime or practicing yoga were excluded.

History was recorded followed by anthropometry and clinical examination.

The height and weight were recorded as per standard procedures. Body mass index (BMI) and Body surface area (BSA) were calculated.



BSA (m²) =0.20247 × Height (m) 0.725 × Weight (kg) 0.425

Resting pulse rate and blood pressure, resting respiratory rate, VO 2 Max, Physical fitness index (PFI), breath holding time (BHT), and 40 mm endurance test time were measured.

VO 2 max by modified Harvard step test

The metronome was set at a rate of 90/min. A wooden bench of 40-cm height was used. The subject was demonstrated the stepping cycle in rhythm with the step frequency. That is, to start with, the subject places one foot on the bench followed by the other foot; then the first foot is brought back down to the floor followed by the other foot, i.e. up-up-down-down. Duration of the test was set at 5 minutes. The subject was closely watched for any signs of discomfort or any of the indications to stop the test. Immediately after finishing the test, the subject's pulse rate was counted using radial artery for full one minute, i.e. from 0-1 minute for VO 2 Max estimation by Astrand-RyhmingNomogram. On the nomogram, the heart rate (0-1 minute) and weight in Kg of the subject were accurately marked on their designated scales. A line was drawn between the two marks and where this line intersected the VO 2 Max line in the middle, the reading was noted. [7]

Physical fitness index

After recording the pulse (0-1 minute) for VO 2 Max estimation, the radial pulse was again counted at intervals of 1-1½, 2-2½, and 3-3½ minutes of completing the test to evaluate the PFI. The PFI was evaluated by using the formula: [8]



Breath holding time

The subject was first explained and demonstrated the technique for breath holding. He was asked to inhale maximally then hold his breath till breaking point was reached, i.e., the point when the subject could no longer hold his breath. The subject was motivated to maximize the breath holding period. The time was noted in seconds by using a stop watch and the value was rounded off to integers. A minimum of three trials were given with a rest period of three minutes between the trials and the highest of three similar best performances was taken for statistical analysis. [8],[9]

The 40 mm Hg test

The subject was explained and demonstrated the correct procedure of the test. The subject was asked to take in a full breath and blow in the tube of the sphygmomanometer so that the mercury level rises up to 40 mm. The subject was instructed to maintain the level as long as he could. The subject was continuously prompted to maintain the level and to prolong the holding period. The subject was also asked not to blow his cheeks while performing the test. Care was taken to see that the subject did not use oral muscles or tongue to develop pressure or block the tubing. A minimum of three trials were given with rest period of three minutes between the trials and the highest of three similar best performances was taken for statistical analysis. [8],[9]

The computer software "SPSS version 16" was used to analyze the data and unpaired T-Test was used to compare the two groups. The data were considered significant and highly significant if the analyzed probability values were (P value) <0.05* and P < 0.01**, respectively.


  Results Top


The mean age of untrained and trained subjects was 18.67 and 18.92 years, respectively, and the difference was not statistically significant (P = 0.26). The difference of height between two groups was not statistically significant (P = 0.68). The mean weight for the trained group was 62.58, and for untrained group was 70.12 kg and the difference was statistically significant (P < 0.001). The mean BMI was 21.17 kg/m 2 and 23.67 kg/m 2 for the trained group and untrained group, respectively, and the difference in BMI was significant (P < 0.001). The BSA of untrained group ranged from 1.51 to 2.11 m 2 with mean being 1.82 m 2 while BSA of physically trained group ranged from 1.58 to 1.85 m 2 with the mean of 1.73 m 2 . Subjects engaged in regular physical activity had statistically lower BSA values than the sedentary group (P < 0.001). The mean pulse rates of trained and the untrained subjects was 76.5/min and 82.73/min, with a statistically significant different P value of < 0.0001. Two third of all untrained subjects had a pulse rate of 80 to 90 per minute while it ranged from 60 to 80 beats per minute for trained soldiers (P < 0.001). The resting blood pressure did not show any significant difference between the two study groups. The difference in mean resting respiratory rates of the trained and untrained groups was statistically significant (P = 0.009) [Table 1]. It was found that all the physically untrained subjects had a VO 2 Max value of less than 55 ml/kg/min (range, 30 to 55 ml/kg/min), while all the physically trained subjects had VO 2 Max of more than 50 ml/kg/min (range, 50 to 80 ml/kg/min). The means were 43.19 and 61.08 ml/kg/min, respectively. The difference in means was statistically highly significant (P < 0.0001). The mean value of PFI of untrained was 80.03 + 8.22 and trained was 91.0 + 6.54, and the difference was highly significant (P < 0.0001). The mean BHT for untrained subjects was 40.02 seconds and for trained subjects it was 57.84 seconds (P < 0.0001). In untrained subjects, the mean 40 mm endurance time was 32.02 seconds while it was 47.56 seconds in physically trained, with P value of < 0.0001 [Table 2].
Table 1: Comparison of basic descriptive statistics

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Table 2: Statistical comparison of means of cardiorespiratory efficiency tests between physically trained and untrained subjects

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  Discussion Top


Very often, it is of interest to know the individual's capacity for physical work, e.g., when selecting people for special tasks in sports, military service, or in industrial work, or controlling the physical condition of athletes. Furthermore, a reduction of this capacity might be the first sign of disease. [10],[11],[12],[13]

Recent research by Ferrara on physical fitness of college students conducted in the year 2009 suggests that approximately 35% of all college students are overweight or obese, with many at risk for weight gain during college years. [14] In the present study too, as many as 32% subjects in the untrained group were overweight or obese (BMI > 25 kg/m 2 ) as against the trained group where no one had a BMI of more than 30 kg/m 2 and only one subject (2%) had a BMI of more than 25 kg/m 2 .

Aires et al. in 2008 studied to establish physical fitness levels in a school population of 11- to 18-year-old students and analyzed differences according to BMI status in overweight subjects. The analysis showed that a low BMI level could significantly improve physical fitness components including VO 2 Max. [11] Gandhi and Gunjan in a recent study attribute nearly 70% of the differences in VO 2 Max scores among individuals to variations in body mass. [10]

The VO 2 Max was found to be significantly higher in trained group. The results of evaluation of VO 2 Max indicate that all the physically untrained subjects had a VO 2 Max value of less than 55 ml/kg/min (range, 30 to 55 ml/kg/min), while all the physically trained subjects had VO 2 Max of more than 50 ml/kg/min (range, 50 to 80 ml/kg/min). The means were 43.19 and 61.08 ml/kg/min, respectively. The difference in means was highly significant (P < 0.0001).

It is prudent to compare our results with some more studies from the Armed forces setting from different parts of the world [Table 3].
Table 3: Effect of training on VO2 max

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A study was carried out on 70 normal healthy Indian Air Force Personnel, 30 of them aircrew and 40 ground duty subjects to assess their Maximal oxygen uptake capacity (VO 2 Max). Their mean absolute VO 2 Max values were found around 2.5 l/min in 21 to 29 years age group. Furthermore, the author states that their mean VO 2 Max per Kg body weight values were 38.6 ml/min/Kg in the aircrew and 40.8 ml/min/Kg in the ground duty subjects. These figures are much lower than the figures found in the present study. The author himself states that these figures from the air force are indicative of relatively lower levels of cardio-respiratory fitness in them as compared to Army personnel in India. This can be explained on the fact that the training in army is more rigorous than the air force. [19]

In a study from England, it is seen that the aerobic fitness measured in a sample of 438 young male Army recruits prior to the commencement of training mean VO 2 Max was found to be 41.7 ± 8.3 ml/kg/min. These figures are comparable to the values of means for untrained subjects in the present study (43.19 ml/kg/min) and much lesser than those for the trained army soldiers in the present study (61.08 ml/kg/min). It could be attributed to the fact that the VO 2 Max of the youth in England is quite comparable to that of India; however, the rigorous training of the army (as seen in Indian trained soldiers) improves the VO 2 Max significantly. [20]

A study by Lim and Lee was conducted in the Singapore armed forces to study effects of 20-week basic military training program on VO 2 Max and aerobic fitness of obese recruits. The results indicate that VO 2 Max of the subjects significantly increased after a 20-week training program. [21]

In the present study, the results of the PFI indicate that most (98%) physically untrained subjects fell in the category of 70 to 100% and no subject had the index of more than 100%, while 12% physically trained subjects had a PFI of more than 100%. The mean PFI for the untrained subjects was found to be 80.03 ± 8.22%, as against a significantly higher mean of 91.04 ± 6.54% for the trained group. The difference in means was statistically highly significant (P < 0.0001).

A study by Darr et al. indicated that trained subjects demonstrated a significantly faster heart rate recovery as compared to untrained subjects. This could be a reason for higher PFI as well. [22] A study by Short and Sedlock showed that trained individuals had shorter excess post exercise oxygen consumption (EPOC) duration than untrained. These findings indicate that trained individuals have faster regulation of post-exercise metabolism. [17]

In the present study, the results of the breath holding test indicate that only 9 (18%) physically untrained subjects could hold their breath for 50 or more than 50 seconds, while as many as 45 (90%) physically trained subjects could hold their breath for this period (more than or equal to 50 seconds). The mean BHT for untrained subjects was 40.02 ± 15.84 seconds and for trained subjects it was 57.84 ± 5.97 seconds. The difference in means of the two groups was statistically highly significant (P < 0.0001). [Table 4] shows effect of training on breath holding test in different studies.
Table 4: Effect of training on breath holding test

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Limitations and future scope

The sample was drawn from one limited geographic area; the results cannot properly be generalized to the national population. Second, because of the cross-sectional design, this study had limited extrapolative value. Future studies may be undertaken to determine the training-induced adaptive changes at cellular level.


  Conclusion Top


Various cardio-respiratory and other fitness parameters were markedly better in the youths who undertake couple of hours of exercise. This better cardio-respiratory fitness is known to translate into a lower cardiac disease risk in future. Simple changes in lifestyle by enhancing physical activity would go a long way.[24]

 
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    Tables

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



 

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