Efficacy of Ashwagandha (withania somnifera [l.] Dunal) in improving cardiorespiratory endurance (VO2 max test) in healthy subjects

Abstract

In Ayurveda, certain herbal formulas are considered to be Rasayana and they are typically taken over periods of time to regenerate both brain and body tissue. Ashwagandha (Withania Somnifera) is used as an adaptogen, antioxidant, immune modulator, free radical scavenger, anti stress, anti arthritic, antispasmodic, anti inflammatory, nervous tonic, nerve soothing and anticancer agent. Ashwagandha (WS) as a nutritional supplement is yet too established. Maximum oxygen uptake (VO2 max) is a gold standard of cardiopulmonary and muscle cell fitness is considered. The study evaluated the efficacy of Ashwagandha to improve cardiorespiratory endurance (VO2 max) in healthy subjects. They randomized single blind controlled comparative clinical study. 54 health volunteers in each group, study group received Ashwagandha Choorna 12gm with milk (200ml) empty stomach in the morning and the control group only milk (200ml). Maximal capacity of oxygen intake in ml/kg/min (VO2 max) with Rockport fitness walking test of both study and control group were measured before intervention (0th day), after the intervention (60th day) and follow up (90th day). A significant improvement in the VO2 max (F=20.675, P <0.0001) and Hemoglobin (X2=74.150 P <0.0001) in the study group was found. Supplementation of Ashwagandha (Withania Somnifera) with milk improve hemoglobin and VO2 max (maximum aerobic capacity).

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BEPLS Vol 10 [11] October 2021 7 | P a g e ©2021 AELS, INDIA
Bulletin of Environment, Pharmacology and Life Sciences
Bull. Env. Pharmacol. Life Sci., Vol 10 [11]October 2021 : 07-12
©2021 Academy for Environment and Life Sciences, India
Online ISSN 2277-1808
Journal’s URL:http://www.bepls.com
CODEN: BEPLAD
ORIGINAL ARTICLE
OPEN ACCESS
Efficacy of Ashwagandha (Withania somnifera) in improving
cardiorespiratory endurance (Harvard step test) in healthy
subjects
Bargale Sushant Sukumar1, Shashirekha H K2
1. Assistant Professor, Department of Swasthavritta and Yoga Sri Dharmasthala Manjunatheshwara
college of Ayurveda and Hospital Hassan, Karnataka.
2. HOD and Associate Professor, Department of Samhita and Sanskrit, Faculty of Ayurveda, IMS, Banaras
Hindu University, Varanasi, UP.
Correspondence Email: dr.sushant99@gmail.com
ABSTRACT
Ayurveda is widely used in India as a primary health care system and is flourishing in the promotion of health worldwide.
Ayurveda aims at maintaining the health of healthy and treating the individuals with diseases. Chakrapani defines
Swasthavritta as the regimens followed to keep oneself healthy and thus, it includes promotion of health and prevention
of diseases. Ashwagandha is one of Ayurveda's most essential herbs, used as Rasayana for its wide range of health benefits
for centuries. Ashwagandha roots are a constituent of over 200 formulations in Ayurveda, Siddha and Unani medicine,
which are used in the treatment of various physiological disorders. Ashwagandha has been used to promote youthful vigor,
strength and health, nurture the body's time elements and increase the production of vital fluids, muscle fat, blood, lymph,
semen and cells. Chronic exhaustion, debility, dehydration, bone weakness, loose teeth, hunger, impotence, premature
ageing, emaciation, weakness and stress of the muscles can also be counteracted. It is also used for constipation, senile
debility, rheumatism, general weakness, nervous exhaustion, memory loss, muscle energy loss and spermatorrhoea
(excessive ejaculation). The study evaluated the efficacy of Ashwagandha (WS) to improve cardiorespiratory endurance
(Harvard step test) in healthy subjects. Study group received Ashwagandha 12gm with milk (200ml) empty stomach in
morning and control group only milk (200 ml). Harvard step test of both study and control group before intervention (0th
day), after intervention (60th day) and follow up (90th day). A significant improvement in the Harvard step test after
intervention in between the group (F=7.996 p=0.003) and follow up (F=7.304 p=0.030). Supplementation of Ashwagandha
(Withania somnifera) improve cardiorespiratory endurance (Harvard step test).
Keywords: Ashwagandha, Withania somnifera, Health, Harvard step test
Received 11.04.2021 Revised 16.06.2021 Accepted 01.09.2021
INTRODUCTION
Ayurvedic medicine is holistic, which means viewing the whole of the body and mind. Not only does
Ayurveda treat the physical ailments of a patient, but it also changes lifestyle practices to help preserve or
improve health.[1] To maintain health, reduce stress, and improve flexibility, strength and endurance,
people use Ayurvedic medicines. Ashwagandha (W. Somnifera) has the property of Rasayana as mentioned
in literature.[2] It not only maintains the equilibrium of Dosha and Dhatu of the body but also promotes the
health. Vatakaphahara, Jara Vyadhi Nashaka, Balya, and Dhatu Vriddhikara are all properties of
Ashwagandha. Because of these qualities, it has not only preventive, but also promotive and curative effects,
as well as the ability to slow down Jara by delaying the pathogenesis.[3] Ashwagandha (WS) promotes good
health, improves quality of life, treats insomnia, drowsiness, physical and mental fatigue, weakness, and
prolongs youth. In Ayurveda, Unani and Siddha, this plant is used in more than 100 formulations. One of
Ashwagandha most important useful drug is Medica Ayurveda Material.[4] Ashwagandha (Withania
somnifera) chemical constituents such as flavonoids, alkaloids, and steroidal lactones (withanolides) or
antioxidants (superoxide dismutase, catalase, and glutathione peroxidase) may be behind Harvard step test
improvement.[5] In healthy adults and also in athletes, Ashwagandha also enhances cardiovascular fitness,
providing an additional alternative as a dietary supplement to boost the cardiorespiratory endurance
(Harvard step test) and improve the quality of life.[6] Physical fitness is defined as the ability to perform a

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physical activity in a variety of environments. Aerobic capacity, muscular endurance, flexibility, and body
composition are the five components. The Harvard Step Test is regarded the gold standard of cardiovascular
and muscle cell fitness.[7] Study the efficacy of Ashwagandha to improve cardiorespiratory endurance
(Harvard step test) in healthy subjects.
MATERIAL AND METHODS
This randomized controlled comparative study with pretest and post test design was approved by IEC Sri
Dharmasthala Manjunatheshwara college of Ayurveda and Hospital Hassan, Karnataka, Indian (IEC No.\:
SDM/IEC/92/2016-2017 date 25 June 2016) and the study was conducted in compliance with good clinical
practice guidelines, declaration of Helsinki and all other applicable regulations. (CTRI no
2019/05/019009)
Source of Data -The subjects were screened and selected from OPD of Sri Dharmasthala
Manjunatheshwara college of Ayurveda and Hospital Hassan, Karnataka.
Method of collection of Data- The selected healthy subjects was done as per the criteria inclusion and
exclusion. Apparently healthy volunteers within the age group 18-40 years ready to give written consent
irrespective of gender were included in the study. The subjects (108) included in study were alternatively
divided into control group (N1=54) and study group (N2=54). In study group administration of
Ashwagandha Choorna (Withania somnifera) given in the dose of 12 grams with 200ml milk in daily
morning empty stomach for a period of 60 days. The control group administration of milk 200ml in daily
morning empty stomach a period of 60 days.The blood, urine routine and lipid profile was analyzed before,
after intervention and follow up (0th, 60th and 90th day); the Cardiorespiratory endurance test (Harvard
test) were assesses through a pre-structured, pre validated questionnaire based on Ayurvedic description
of health. Data analyze was done by SPSS 20 version.
Inclusion criteria:
1. Apparently Healthy subjects who are interested and willing to take Ashwagandha Churna.
2. Subjects of age group 18-40 yrs.
Exclusion Criteria-
1. Pregnant women, lactating women etc.
2. Those on other supplements.
Duration of the study: For both groups60 days.
Follow up: After 1 month of completion on intervention.
Operational definitions/Techniques employed:
Method of sample selection – Healthy Volunteers
Study design- Controlled comparative clinical study with pre-test and post-test design wherein 108
apparently healthy subjects were selected.
Method of Sampling- Convenient sampling method.
Method of group allocation- Simple random sampling technique viz., alternate group distribution.
Interventions-
Medicine Name: Ashwagandha Choorna
Authentication of Drugs - Ashwagandha Choorna purchased from SDM pharmacy Udupi, Karnataka.
Packaging and labeling- 12 gm of Ashwagandha Churna were measures each dose packed separately in
small Ziploc plastic covers and placed in a big size bottles.
Route of Drug administration- Oral
Form of drug - Choorna (powder)
Dosage of the drug-12gm
Anupana- Milk
Sample Size- 108 persons were screened and selected from OPD of SDM Ayurveda College and Hospital,
Hassan.
Grouping- Control Group 1 - 54 subjects and Study Group 2- 54 subjects
Intervention-
The included subjects are divided under two groups Control Group 1 and Study group 2.
GROUP 1 - 54 persons were given 2 Haritaki tablets for KosthaShuddhi with hot water for days and 200 ml
Dugdha (milk) for 60 days in empty stomach early in the morning kept as a control.
GROUP 2 - 54 persons were given 2 Haritaki tablets for KosthaShuddhi with hot water for 3 days and 12gm
of Ashwagandha Choorna with 200 ml Dugdha (milk) for 60 days in empty stomach early in the morning.
Harvard Step Test-
Equipment required: The height of the platform is about 50 cm (20 inches) for men and 40 cm (16 inches)
for women, stop watch, pulse oxy meter.
Procedure:

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1. The athlete steps up and down on the platform at a rate of 30 steps per minute (every two seconds) for
5 minutes or until exhaustion. Exhaustion is defined as the athlete's inability to maintain a 15-second
stepping rate.
2. The athlete immediately sits down on completion of the test, and the total number of heart beats are
counted between 1 to 1.5 minutes after finishing.
3. This is the only measure required if using the short form of the test.
4. If the long form of the test is being conducted, there is an additional heart rate measures at between 2
to 2.5 minutes, and between 3 to 3.5 minutes.
Scoring: the Fitness Index score is determined by the following equations. For example, if the total test
time was 300 seconds (if completed the whole 5 minutes), and the number of heart beats between 1-1.5
minutes was 90, between 2-2.5 it was 80 and between 3-3.5 it was 70, then the long form Fitness Index
score would be: (100 x 300) / (240 x 2) = 62.5. Note: you are using the total number of heart beats in the
30 second period, not the rate (beats per minute) during that time.
Fitness Index (long form) = (100 x test duration in seconds) divided by (2 x sum of heart beats in the
recovery periods).[8,9,10]
Grading assessment of Harvard step test.
Grade
Rating
Fitness index (long form)
1
Excellent
> 96
2
Good
83 – 96
3
Average
68 – 82
4
low average
54 – 67
5
Poor
< 54
(norms from: Fox et al. 1973)
RESULT
Total 408 subjects were screened, 114 subjects were enrolled for the study, 108 subjects completed the
clinical trial and there was 6 subjects was drop out.
Age distribution- Among 114 subjects, majority of 102 (89.45%) had completed the schooling till PUC and
12 (10.52%) subjects were graduates.
Educational Status- Among 114 subjects, majority of 102 (89.45%) had completed the schooling till PUC
and 12 (10.52%) subjects were graduates.
Type of family- Among 114 subjects, majority of 84 (73.67%) subjects having joint family and 30 (26.33%)
subjects having nuclear family.
Housing condition- Among 114 subjects, majority of 70 (61.39%) subjects having poor housing condition,
32 (28.09%) subjects having moderate housing condition, 10 (8.77%) subjects having good housing
condition and 02 (1.75%) having very good housing condition.
Food Habits (Vegetarian or Mixed)- Among 114 subjects, all the subject having mixed food (vegetarian
and non-vegetarian).
Food consumption (Timely consumption / Untimely consumption / frequent food intake)-Among
114 subjects, majority 86 (75.44%) consume the food timely and 28 (24.56) consume untimely.
The Friedman test is non parametric alternative alternate to the one way ANOVA with repeated measures.
It is used to test for differences between groups when the dependent variable being measures is ordinal. It
can also be used to analyze continuous data that deviates from the assumptions required for one-way
ANOVA with repeated measures. Friedman’s test followed by post hoc analysis with Wilcoxon signed rank
test was applied for subjective parameters. In the parameters N was fixed to 54 in each group. The study's
initial significance level was set at 0.05.The subjects were analyzed at interval of BT (Before Intervention-
i.e. on baseline or 0th day), AT (After Intervention i.e. on 60th day) and FU (Follow up i.e. 90 day).
Table No 01- Descriptive Statistics for Friedman test in Harvard step test
Harvard step test
Control Group
Study Group
N
Mean
SD
N
Mean
SD
BT (0th day)
54
2.759
.5472
54
2.9259
.26435
AT (60th day)
54
2.537
.5734
54
2.2222
.50157
FU (90th day)
54
2.555
.5718
54
2.3333
.47583
Table No 02- Descriptive Statistics for Friedman test in Harvard step test
Harvard step test
Control Group
Study Group

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N
Mean
SD
N
Mean
SD
BT (0th day)
54
79.6808
5.25325
54
77.5206
5.21865
AT (60th day)
54
81.4401
5.01079
54
83.3287
5.03840
FU (90th day)
54
81.6658
5.40752
54
82.7652
5.09379
Control Group- The mean physical fitness index (Harvard step test) in the control group was 79±5.25
which increased to 81.44±5.01 after intervention and after the follow up 81.66±5.40. Physical fitness index
(Harvard step test) showed statistically significant change with p<0.001.
Study Group- The mean physical fitness index (Harvard step test) in the Study group was 77.52±5.21
which increased to 83.32±5.03 after intervention and after the follow up 82.76±5.09. Physical fitness index
(Harvard step test) showed statistically significant change with p<0.0001.
Table No03- Friedman Test in Harvard step test
Harvard step test Control Group
N
MR
X2
Df
P
Remarks
BT (0th day)
54
2.21
19.00
2
<0.0001
S
AT (60th day)
54
1.88
FU (90th day)
54
1.91
Harvard step test Study Group
N
MR
X2
Df
P
Remarks
BT (0th day)
54
2.65
62.600
2
<0.0001
S
AT (60th day)
54
1.59
FU (90th day)
54
1.76
Table No 04- Ranks for Wilcoxon test in Harvard step test
Harvard step test
Control Group
Study Group
N
MR
Sum of Ranks
N
MR
Sum of Ranks
AT – BT
NR
0
.00
.00
0
.00
.00
PR
12
6.50
78.00
38
19.50
741.00
Ties
42
16
Total
54
54
FU – AT
NR
3
3.00
9.00
8
5.50
44.00
PR
2
3.00
6.00
2
5.50
11.00
Ties
49
44
Total
54
54
FU – BT
NR
0
.00
.00
0
.00
.00
PR
11
6.00
66.00
32
16.50
528.00
Ties
43
22
Total
54
54
Table No 05 - Wilcoxon signed rank Test in Harvard step test
Harvard step test
Control Group
Study Group
AT – BT
FU – AT
FU – BT
AT – BT
FU – AT
FU – BT
Z value
-3.464
-.447
-3.317
-6.164
-1.897
-5.657
Asymp. Sig. (2-tailed)
( P value)
0.001
.655
0.001
<0.0001
0.058
<0.0001
Remarks
HS
NS
HS
HS
NS
HS
Control Group- There was statistically significant difference in Harvard step from BT (0th day) to AT (60th
day) and FU (90th day), χ2= 19.00, p< 0.0001. Post hoc analysis with Wilcoxon signed-rank tests was applied
resulting and it also significance changes. There was significant differences between BT (0th day) to AT (60th
day) (Z = -3.464, p<0.0005), in between AT (60th day) to FU (90th day) (Z = -3.317, p = 0.001). There was no
significant differences between BT (0th day) to FU (90th day) (Z = -.447, p =0.655).
Study Group- There was statistically significant difference in Harvard step from BT (0th day) to AT (60th
day) and FU (90th day), χ2= 62.600, p< 0.0001. Post hoc analysis with Wilcoxon signed-rank tests was
applied resulting and it also significance changes. There was significant differences between BT (0th day) to
AT (60th day) (Z = -6.164, p<0.0005), in between BT (0th day) to FU (90th day) (Z = -2.449, p<0.0005). There
was no significant difference in between AT (60th day) to FU (90th day) (Z = -1.897, p = 0.058).
COMPARE IN CONTROL GROUP AND STUDY GROUP-
Mann-Whitney U test is used to compare differences between two independent groups when the dependent
variable is either ordinal or continuous, but not normally distributed.
In the parameter N was fixed to 54 in each group Total 108 subjects. The initial significance level considered
in this study is 0.05. The subjects were analyzed at interval of BT (Before Intervention- i.e. on baseline or
0th day), AT (After Intervention i.e. on 60th day) and FU (Follow up i.e. on 90 day).

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Table No 06- Descriptive Statistics in Harvard step test in between group (Control group and study
group)
Harvard step test
Group
N
Mean
Std. Deviation
Std. Error Mean
AT (60th day)
Control Group
54
2.5370
.57340
.07803
Study Group
54
2.2222
.50157
.06826
FU (90th day)
Control Group
54
2.5556
.57188
.07782
Study Group
54
2.3333
.47583
.06475
Table No 07- Independent sample test in Harvard step test in between group (Control group and
study group) AFTER INTERVENTION
Harvard step test
Equal variances assumed
Equal variances not assumed
Levene's Test for Equality of Variances
F
7.996
Sig.
.006
t-test for Equality of Means
T
3.037
3.037
Df
106
104.156
Sig. (2-tailed)
0.003
0.003
Remarks
S
S
Mean Difference
.31481
.31481
Std. Error Difference
.10367
.10367
95% Confidence Interval of the Difference
Lower
.10928
.10924
Upper
.52035
.52039
This study found that statistically significantly Harvard step test increase in the (2.22± 0.50) after
intervention at the study group compare to control group (2.53±0.57), t(106)= 3.037, p=0.003.
Table No 08- Independent sample test in Harvard step test in between group (Control group and
study group) FOLLOW UP
Harvard step test
Equal variances assumed
Equal variances not assumed
Levene's Test for Equality of Variances
F
7.304
Sig.
.008
t-test for Equality of Means
T
2.195
2.195
Df
106
102.608
Sig. (2-tailed)
0.030
0.030
Remarks
S
S
Mean Difference
.22222
.22222
Std. Error Difference
.10124
.10124
95% Confidence Interval of the Difference
Lower
.02151
.02143
Upper
.42294
.42301
This study found that statistically significantly Harvard step test increase in the (2.33± 0.47) after
intervention at the study group compare to control group (2.55±0.57), t(106)= 2.195, p=0.030.
DISCUSSION
Apparently healthy subjects consumed in 12 grams in Ashwagandha Choorna with 200ml milk on daily
basis, it has all possibility to show the effect as Rasayana. In study group shows that improve the
cardiorespiratory endurance (Harvard test). Ashwagandha (Withania somnifera) reduced oxidative stress,
as various oxidants and improve level of diverse anti-oxidants. Harvard step test represent long term
aerobic and cardiovascular endurance. Endurance training combined with a favourable genetic disposition,
results in series of physiological adaptations, designed to maximize endurance performance by increasing
the amount of oxygen, which can be delivered to utilized by working muscle. [11]
Exercises that cause damage to amount of different human body systems are long-term strenuous free
radical release. Increased lipid peroxidation may be caused by stress, whereas catalase and glutathione
peroxidase enzymes minimise antioxidant levels. All of the above parameters of free harm are standardised
in a dose-dependent manner when researchers administered Ashwagandha (Withania somnifera) one hour
prior to a daily stress-inducing therapy.[12]
Ashwagandha (Withania somnifera) chemical constituents such as flavonoids, alkaloids, and steroidal

BEPLS Vol 10 [11] October 2021 12 | P a g e ©2021 AELS, INDIA
lactones (withanolides) or antioxidants (superoxide dismutase, catalase, and glutathione peroxidase) may
be behind cardiorespiratory endurance (Harvard step test) improvement. In healthy adults and also in
athletes, Ashwagandha also enhances cardiovascular fitness, providing an additional alternative as a dietary
supplement to boost the Harvard step test measure.[13]
The active principles of Ashwagandha (Withania somnifera), VII-X sitondosides and withaferin A
(glycowwithanolides) have been evaluated for antioxidant activity using the major free radical scavenging
enzymes in the frontal cortex and striatum of the rat brain, superoxide dismutase (SOD), catalase (CAT) and
glutathione peroxidase (GPX).[14]
CONCLUSION
Ashwagandha (Withania somnifera) an important drug in Ayurveda in traditional Indian system medicine
is conserved to be a Rasayana (rejuvenating). In this clinical study, oral administration of Ashwagandha
(WS) with milk enhance aerobic capacity (Harvard step test) in healthy subjects. The finding of this clinical
study suggests that Ashwagandha improves cardiovascular dynamics by increasing Harvard step test,
thereby enhancing cardiorespiratory endurance in healthy subjects.
ACKNOWLEGEMENT
The authors acknowledge the subjects who were involved in the study.
CONFLICT OF INTEREST
The authors declare that there is no conflict of interest for this study.
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CITATION OF THIS ARTICLE
B S Sukumar, Shashirekha H K. Efficacy of Ashwagandha (Withania somnifera) in improving cardiorespiratory
endurance (Harvard step test) in healthy subjects. Bull. Env. Pharmacol. Life Sci., Vol 10[11] October 2021 : 07-12.