|Year : 2015 | Volume
| Issue : 2 | Page : 153-159
Effects of exercise training on correlation of VO 2 max and anthropometric parameters, physical fitness index in young adult Indian males
Rajshree Gupta1, Arunima Chaudhuri2, RK Gupta3, Nishant Bansod4
1 Department of Physiology, Army College of Medical Sciences, New Delhi, India
2 Department of Physiology, Burdwan Medical College and Hospital, Burdwan, West Bengal, India
3 Department of Community Medicine, Army College of Medical Sciences, New Delhi, India
4 Department of Physiology, Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha, Maharashtra, India
|Date of Web Publication||6-May-2015|
Department of Physiology, Krishnasayar South, Borehat, Burdwan - 713 102, West Bengal
Source of Support: None, Conflict of Interest: None
Background: The lack of physical activity and sedentary lifestyles in the young generation have been a matter of concern in recent days, and about 3.3% of all deaths can be attributed to physical inactivity. Aims: To assess the effects of an exercise program on correlation of VO 2 max and anthropometric parameters, Physical Fitness Index (PFI). Materials and Methods: This pilot project was carried in a time span of 2 years in a tertiary care hospital on 100 young adult male subjects. Untrained Group comprised of 100 healthy young adult males. History was recorded followed by anthropometry and clinical examination. Body mass index (BMI) was calculated. Resting pulse rate, blood pressure, heart rate variations during deep breathing, VO 2 max, PFI were measured. These subjects were given training of aerobic exercises for a time span of 1 year. After completion of 1 year of training, all parameters were re-evaluated. Results: BMI, pulse rate and blood pressure, were significantly lower in trained individuals. Heart rate variations during deep breathing, VO 2 max, PFI were significantly increased following training. A good negative correlation was seen between BMI and VO 2 max amongst the untrained subjects (Pearson coefficient of −0.673), which was statistically significant at P < 0.0001. However, the correlation between VO 2 max and BMI amongst the trained subjects was a weak negative correlation (Pearson's correlation coefficient of −0.202. The correlation between VO 2 max and pulse amongst the trained subjects also showed a negative correlation with a Pearson's correlation coefficient of −0.271. The correlation between VO 2 max and PFI amongst the trained subjects was strong with a Pearson's correlation coefficient of 0.792. Conclusions: Regular exercise training decrease resting pulse rate, blood pressure and increase VO 2 max, heart rate variations during deep breathing, PFI. These positive physiological outcomes of exercise and training have important implications in the prevention of cardiovascular diseases and needs to be popularized among younger generations.
ةيندبلا ةقايللا رشؤمو ةيرشبلا تاسايقلاو VO2max رشؤمو يندبلا طاشنلا نيب ةلدابتملا ةقلاعلادنهلا يفروكذلا نيغلابلا بابشلا يف
ىهو ، قلقلل ةريثم بابشلا ليج يف ةرقتسملا ةايحلا طامنأو يندبلا طاشنلا ةلق تحبصأ ةريخلأا مايلأا يف :ثحبلا ةيفلخ تايفولا عيمج نم ٪3.3ل اببس لثمت
تارشؤمو سكام VO2max نيب و هنيب ةلدابتملا ةقلاعلا و يندبلا طاشنلا ةسرامم ىلع ةبترتملا راثلآا مييقت :فادهلأا . ةيندبلا ةقايللا ةيندبلا رشؤم و ،ةيرشبلا تاسايقلا
روكذلا بابشلا نم 100 ىلع ةيحصلا ةياعرلا ىفشتسم يف نيماع تقرغتسا ةينمز ةرتف يف عورشملا اذه ذيفنت مت :قرطلاو داوملا متو .يريرسلا صحفلاو ةينامسجلا تاسايقلا و خيراتلا ليجست مت . نيبردملا ريغ نم مهعيمجو 100 نم ةعومجملا تفلأتو .نيغلابلا سايق مت ،قيمعلا سفنتلا للاخ اهتافلاتخا و بلقلا تابرض لدعمو مدلا طغضو ضبنلا لدعم .)BMI( مسجلا ةلتك رشؤم باسح اضيا .ةقباسلا تارشؤملاا عيمج مييقت ةداعإ تمت ،بيردتلا نم ءاهتنلاا دعب. ماع ةرتفل ةيئاوهلا نيرامتلل ةساردلا ةنيع تعضخأ . VO2max
بلقلا تابرض لدعم نأ امك .نيبردملا دارفلأا يف ريثكب كلذ نم لقأ ،مدلا طغضو ضبنلا لدعمو ،مسجلا ةلتك رشؤم ناك :جئاتنلا رشؤم و مسجلا ةلتك رشؤم نيب ةديج ةيبلس ةقلاع ةساردلا ترهظأ دقو .بيردتلا دعب ظوحلم لكشب تداز دق ،قيمعلا سفنتلا ءانثأ عمو .P < 0.0001 دنع ةيئاصحإ ةللاد اذ ناك يذلا ،)0.673- لماعم نوسريب( نيبردملا ريغ صاخشلأا ىدل VO2 max رهظأ .0.202-لل نوسريب طابترا لماعم( ايبلس نيبردملا صاخشلأا ىدل مسجلا ةلتك و VO2 max شؤم نيب طابترلاا ناك ،كلذ نوسريب طابترا لماعم عم ةيبلس ةقلاع دوجو اضيأ نيبردملا صاخشلأا ىدل ضبنلا لدعم و VO2maxرشؤم نيب ةقلاعلا )0.792 نوسريبل طابترلاا لدعم( ةيوق نيبردملا صاخشلأا ىدل مسجلا ةلتك نيبو VO2 max رشؤم نيب ةقلاعلاا ناكو -0.271
، VO2max رشؤم ةدايزو مدلا طغضو ضبنلا لدعم ضافخنا ىلع دعاست ةمظتنملا نيرامتلا :تاجاتنتسلاا ةسراممل ةيباجيلإا ةيجولويسفلا جئاتنلا نم ةقلاعلا هذه دعتو ،قيمعلا سفنتلا ءانثأ بلقلا تابرض لدعم يف تافلاتخلااوةباشلا لايجلأا نيب عاشت نأ ىلإ جاتحتو ةيومدلا ةيعولأاو بلقلا ضارمأ نم ةياقولا يف ةمهم راثآ اهل ثيح تابيردتلا
Keywords: Exercise training, VO 2 max, physical fitness index
|How to cite this article:|
Gupta R, Chaudhuri A, Gupta R K, Bansod N. Effects of exercise training on correlation of VO 2 max and anthropometric parameters, physical fitness index in young adult Indian males. Saudi J Sports Med 2015;15:153-9
|How to cite this URL:|
Gupta R, Chaudhuri A, Gupta R K, Bansod N. Effects of exercise training on correlation of VO 2 max and anthropometric parameters, physical fitness index in young adult Indian males. Saudi J Sports Med [serial online] 2015 [cited 2023 Jun 5];15:153-9. Available from: https://www.sjosm.org/text.asp?2015/15/2/153/156348
| Introduction|| |
Cardiovascular diseases are the leading cause of death worldwide and it has been estimated that 9.4 million deaths each year. , With rapid urbanization, industrialization and increasing level of affluence, load of "noncommunicable diseases" are increasing tremendously. WHO estimate indicates that globally, physical inactivity accounts for more than one-fifth of all the ischemic heart disease cases. About 3.3% of all deaths can be attributed to physical inactivity. The lack of physical activity and sedentary lifestyles in the young generation have been a matter of concern in recent days. ,
Exercise decreases systemic vascular resistance in which the autonomic nervous system and renin-angiotensin system are most likely the underlying regulatory mechanisms. Also, increase of nitric oxide production causes a vasodilation in response to regular aerobic exercise. ,,,,
VO 2 max has been defined, as the level of oxygen consumption beyond which no further increase in oxygen consumption occurs with further increase in the severity of exercise. , The idea that the human body cannot survive without oxygen has been known for millennia. However, the notion that oxygen and its delivery and subsequent metabolism by exercising muscles is crucial to prolonged activity is relatively new, having first gained attention in the 1920s with the work of the English physiologist A. V. Hill. He considered the maximal oxygen uptake (VO 2 max) as the single best measure of cardiorespiratory efficiency.  Since then it has become an accepted way to measure cardiorespiratory efficiency.
So the present study was undertaken to find efficacy of an exercise training program in an urban population of a developing country by assessing correlation of VO 2 max, anthropometric parameters and Physical Fitness Index (PFI). This study may be of use to make the young generation aware about the importance of physical fitness as to prevent lifestyle related chronic diseases.
| Materials and methods|| |
The present pilot study was undertaken in a tertiary care hospital after taking Institutional ethical clearance and informed consent of the subjects in a time span of 2 years.
Physically untrained young adult males in the age group of 20-30 years who had joined different physical training centers and were willing to participate in the study were included. Young males were only included as premenopausal females are usually protected from cardiovascular diseases due to the presence of female sex hormones.
The individuals taking any type of regular medication that may affect autonomic reflexes were excluded. Subjects with history of prolonged medication or prolonged hospitalization, major surgery, any chronic illness of the cardiovascular system, hypertension, respiratory diseases, and neuromuscular disorders were excluded from the study. Tobacco addicts, smokers, and alcoholics were also excluded. Subjects having resting systolic blood pressure more than 140 mmHg or diastolic more than 90 mmHg were not included in the study as blood pressure above this may be indicative of hypertension. Subjects undertaking any yoga or meditation practices, or engaged in sports activity were excluded. Vegetarians were excluded as diet plays an important role in the regulation of autonomic functions.
Sampling was performed using multistage and random cluster method. The first stage of sampling included a simple random sample to select five physical training schools in the region. In the second stage of sampling, 40 newly joined subjects were randomly selected from each institution, who were then administered questionnaires to take history. Hundred and six persons who met the inclusion and exclusion criteria were recruited for the study.
They were clinically examined thoroughly and subjects having resting systolic blood pressure more than 140 mmHg or diastolic more than 90 mmHg were not included in the study. In six subjects blood pressure recorded was above normal level. So the sample size came down to 100.
The height and weight were recorded as per standard procedures. Body mass index (BMI) was calculated.
Resting pulse rate and blood pressure, heart rate variations during deep breathing, VO 2 max, PFI were measured.
Heart rate variation during deep breathing
After a 5 min rest, the patient was instructed to take deep inspiration over 5 s and followed by expiration over next 5 s for 1 min. Expiration: Inspiration ratio of heart rate variation was calculated using Polyrite D. This test is considered to be a very dependable test to assess cardiac autonomic functions with high specificity and sensitivity.
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, that is, up-up - down-down. Duration of the test was set at 5 min. 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 1 min that is, from 0 to 1 min for VO 2 max estimation by Astrand-Ryhming nomogram. On the nomogram, the heart rate (0-1 min) and weight in kilogram 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.
Physical Fitness Index
After recording the pulse (0-1 min) for VO 2 max estimation, the radial pulse was again counted at intervals of 1-1½, 2-2½ and 3-3½½ min of completing the test to evaluate the PFI. The PFI was evaluated using the formula:
These young males (mean age was 25 [4.4] years) were given various types of physical training/exercise for 1 year. The schedule of daily routine for physical training was on an average 5 days a week. The pattern of training involved predominantly aerobic exercises. The training consisted of aerobic exercises for 45 min to 1 h daily and for 5 days in a week. 10 min of warm-up followed by 2.5-5 km run or 60 min of games, in which they played volleyball or basketball.
After 1 year of training, all parameters of the subjects were re-evaluated using the same tests. Subjects were regularly followed up in the time interval. They were not put on any dietary regime and were taking their usual diet that they were used to before joining the training centers.
The computer software "SPSS version 16" (SPSS Inc., Chicago, IL, USA) was used to analyze the data. All data were presented as mean ± SD Student's paired t-test (two-tailed) were used to assess the effect of exercise on different parameters. Pearson's correlation coefficient was calculated between the independent variable (VO 2 max) and the dependent variables (BMI, pulse rate, and PFI) to understand the effect exercise on cardiovascular profile. The data was considered significant and highly significant if the analyzed probability values were P < 0.05* and P < 0.01** respectively.
| Results|| |
Body mass index, pulse rate, and blood pressure, were significantly lower in trained individuals. Heart rate variation during deep breathing, VO 2 max and PFI increased following training (P < 0.0001), as shown in [Table 1]. [Table 2], [Table 3] and [Figure 1], [Figure 2] depict the correlation between VO 2 max and BMI amongst untrained and trained subjects respectively. A good negative correlation is seen between these two variables amongst the untrained subjects (Pearson coefficient of −0.673), which was statistically significant at P < 0.0001. However, the correlation between VO 2 max and BMI amongst the trained subjects was a weak negative correlation (Pearson's correlation coefficient of −0.202, P value 0.159:insignificant). [Table 4] and [Table 5]A depict the correlation between VO 2 max and pulse amongst untrained and trained subjects respectively. A negative correlation is seen between these two variables amongst the untrained subjects (Pearson coefficient of −0.115, P value of 0.43:insignificant). The correlation between VO 2 max and pulse amongst the trained subjects also showed a negative correlation with a Pearson's correlation coefficient of −0.271 and P value of 0.05 (insignificant). [Table 5] B, [Table 6] and [Figure 3] and [Figure 4] depict the correlation between VO 2 max and PFI amongst untrained and trained subjects respectively. A strong positive correlation was seen between these two variables amongst the untrained subjects (Pearson coefficient of 0.635), which was statistically significant at P < 0.0001. The correlation between VO 2 max and PFI amongst the trained subjects was even stronger with a Pearson's correlation coefficient of 0.792, P < 0.0001.
|Figure 1: Correlation between VO2 max and body mass index: Untrained subjects|
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|Figure 2: Correlation between VO2 max and body mass index: Trained subjects|
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|Figure 3: Correlation between VO2 max and Physical Fitness Index: Untrained subjects|
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|Figure 4: Correlation between VO2 max and Physical Fitness Index: Trained subjects|
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|Table 1: Comparisons of different parameters of trained|
and untrained subjects
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|Table 2: Correlation between BMI and VO2 max: Distribution of untrained subjects|
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|Table 3: Correlation between BMI and VO2 max: Distribution of trained subjects|
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|Table 6: Correlation between PFI and VO2 max: Distribution of trained subjects|
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| Discussion|| |
In the present study, it was found that regular exercise training for 1 year increased VO 2 max, heart rate variation during deep breathing, PFI and decreased resting pulse rate, blood pressure. These changes reduce metabolic demands on cardiac muscle, spare the heart from undue exertion and help increase the cardiac output when required (as during strenuous exercise). These positive physiological outcomes of exercise and training have important implications in the prevention of cardiovascular diseases. Exercise as a lifestyle modification is beneficial to a wide variety of health conditions. Specific to hypertension, the benefits of exercise have been promoted by a number of organizations and agencies including the American Heart Association, the American College of Sports Medicine, the Surgeon General of the United States, The National Institutes of Health, and the Centers for Disease Control (Wallace, 2003).
Body mass index and VO 2 max
There seems to be a strong relationship between the BMI and the VO 2 max. A good negative correlation is seen between these two variables amongst the untrained subjects (Pearson coefficient of −0.673), which is statistically significant at P < 0.0001. However, the correlation between VO 2 max and BMI amongst the trained subjects was a weak negative correlation (Pearson's correlation coefficient of −0.202, P = 0.159).
Study conducted by Aires et al. in 2008 showed that a low BMI level significantly improved VO 2 max. This study substantiates the findings of the present study. 
A study by Mota et al. undertaken in 2006 examined the association of cardiorespiratory fitness with BMI in young children. The study clearly showed that cardiorespiratory fitness improves with a reducing BMI. 
Resting pulse rate and VO 2 max
A negative correlation is seen between these two variables amongst the untrained subjects (Pearson coefficient of −0.115). The correlation between VO 2 max and pulse amongst the trained subjects also showed a negative correlation with a Pearson's correlation coefficient of −0.271.
Lower resting pulse rate indicates adaptive changes that take place in the cardiovascular system because of aerobic training. These include hypertrophy of heart musculature resulting into larger stroke volume at rest and also lower resting pulse rate. These two factors lead to increase in VO 2 max in trained subjects. As it has already been elaborated that both maximal cardiac output (stroke volume × heart rate) and maximal oxygen extraction by the tissues improve with physical training and both these parameters are important for the VO 2 max. 
A study conducted by Larry concluded that there is a close relationship between VO 2 max and vagal tone in control of resting heart rate. Individuals with higher aerobic power maintain lower resting heart rates mainly via an increase in parasympathetic tone. 
Physical fitness index and VO 2 max
A strong positive correlation was seen between these two variables amongst the untrained subjects (Pearson coefficient of 0.635), which was statistically significant at P < 0.0001. The correlation between VO 2 max and PFI amongst the trained subjects was even stronger with a Pearson's correlation coefficient of 0.792.
The strong positive correlation between these two variables suggests that those subjects with high physical fitness level have better cardiorespiratory efficiency as both these parameters are indicators of cardiorespiratory fitness.
Similar results are found in a study aimed to assess and compare the physical fitness and cardio respiratory fitness in terms of maximum aerobic capacity (VO 2 max) among the urban female students and rural female students of West Bengal. PFI score of urban and rural female students is positively and highly correlated with VO 2 max. On the basis of highly significant correlation and regression between PFI and VO 2 max was found to be among the urban young female students (r = 0.90, P < 0.001) and rural young female students (r = 0.82, P < 0.001) respectively. 
Another Indian study conducted by Das and Dhundasi on physical fitness among children reveals that VO 2 max significantly correlates with PFI score with correlation coefficient r = 0.26, P < 0.05. 
In another study, physical fitness was assessed in two groups of young college students, sedentary (n = 188) and physically active (n = 164), by a modified Harvard step test suitable for Indian subjects. Mean PFI score was found to be significantly higher (P < 0.001**) in the physically active group of students. It was found that PFI scores of more than 65% of the total of 352 students fell in the "average" category. PFI was found to have significant negative correlation (P < 0.001**) with resting heart rate (both in sitting and standing postures). 
The higher PFI may also be due to lesser pulse rate rise in the trained individuals during exercise. With training, there is an increase in the number of mitochondria. The enzyme system that is involved in oxidative metabolism becomes more efficient. The number of capillaries to muscle cells also increases with better distribution of blood to the muscle fibers. The net effect is a complete extraction of O 2 and consequently, for a given workload, less increase in lactate production. This effect leads to less hypoxia that in turn leads to less chemoreceptor trigger and less cardio-acceleratory effect. For the same intensity of exercise, this induces less increase in heart rate and cardiac output in trained individuals as compared to untrained ones. ,,
The physically trained individuals have higher stroke volume during exercise as they have exercise-induced physiological cardiac hypertrophy; "Athlete's Heart." This leads to increase end-diastolic volume (preload), which in turn leads to more initial length of the muscle fiber. During the exercise of same intensity, the trained subjects achieve the required cardiac output by increasing the stroke volume rather by increasing in heart rate. In contrast, untrained subjects would achieve the required cardiac output by increasing the heart rate. This explains why physically trained people have lesser rise in heart rate during exercise.
Physical fitness Index of a person represents cardiovascular fitness, and it depends on the post exercise recovery of the frequency of the heartbeat. , Trained subjects, irrespective of age, demonstrate a significantly faster heart rate recovery as compared to untrained subjects. This could be a reason for higher PFI as well. ,,
Less cardiorespiratory stress for a given workload in trained individuals could be a reason for faster heart rate recovery and consequently higher PFI. 
A study was conducted in 2013 to examine the relationship between elevated BMI and selected physical fitness variables in male handball players. In adolescent players, BMI was inversely related with counter movement jump (r = −0.26, P < 0.05), mean power during a 30-s Bosco test (r = −0.30, P < 0.001) and handgrip muscle strength (r = −0.52, P < 0.001). Further, BMI was in direct relationship with fatigue index of the Wingate anaerobic test (r = 0.29, P < 0.05). Correspondingly lower and nonsignificant correlations were found in adult players. The study indicates that elevated BMI is more strongly inversely related to physical fitness in adolescent compared to adult team handball players.  So lifestyle modifications with physical exercises need to be implemented early in life. 
Limitations of the study and future scope
The present study indicates the cardiorespiratory changes in relation to physical activity at a gross level. Future studies may be undertaken to determine the training-induced adaptive changes at cellular level. Also, studies can be aimed to design and compare various pattern of regular training, which can be beneficial to the younger generation and can be implemented easily.
| Conclusion|| |
In the present study, it was found that regular physical exercise has a tremendous influence on BMI, which in turn significantly affect the cardiorespiratory efficiency. The predominant influence is by decreasing resting heart rate and improving the aerobic capacity. It is also found that regular exercise training increase heart rate variations during deep breathing, VO 2 max, PFI and decrease resting pulse rate, blood pressure. These changes reduce metabolic demands on cardiac muscle, spare the heart from undue exertion and help increase the cardiac output when required (as during strenuous exercise). These positive physiological outcomes of exercise and training have important implications in the prevention of cardiovascular diseases, and the younger generation needs to be made aware to prevent the epidemic of cardiovascular disease and obesity.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]