Chapter 1
Introduction
Obesity is simply defined as a condition in which excess body fat is accumulated.
The definition of obesity is based on the Body Mass Index (BMI; weight (kg)/height (m2).
It is generally agreed that a BMI of greater than 30 is indicative of obesity, while a BMI of
25.0-29.9 is suggestive of overweight in an individual. BMI ranging between 18.5- 24.99
is considered as normal weight range BMI (Centers for Disease Control and Prevention,
2009). Obesity is increasing at an alarming rate throughout the world and has become a
global problem. The World Health Organization (WHO, 2002) has declared that due to
overweight many health risks may occur. According to recent estimates, there are more
than one billion overweight people worldwide, and approximately 250 million of people to
be clinically obese (WHO, 1998a). World health organized presented the data and
standards based on reports from different countries. Reports from 79 developing countries
including a number of industrialized countries suggest that about 22 million children five
years old are overweight worldwide (WHO, 1998b). Once considered a problem related to
affluence, obesity is now fast growing in many developing countries and also in the poor
neighbourhoods of the developed countries (WHO, 2003; WHO, IASO, & IOTF, 2000).
Obese people suffer from guilt, depression, anxiety and low self-esteem. In
addition to this there is increased incidence of high blood pressure, increased level of
cholesterol and other lipids in the blood, increased diabetes and colon cancer, liver
ailments, mechanical difficulties particularly back and foot problems in obese and
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overweight subjects (Lew and Garfinkel, 1979; Larsson et al, 1981; Hubert et al, 1983;
Dyer and Elliott, 1989; Chute et al, 1991; Stampfer et al, 1992; Lipton et al, 1993; Young
et al, 1993; Hochberg et al, 1995; Tchernof et al, 1996; Ford et al, 1997; Rexrode et al,
1997). In the field of public health, obesity constitutes one of the important medical and
public health problems (Berke and Morden, 2000). Modernisation has led to excess foods
those rich in fats along with decrease in physical activity of people leading to conditions
that favour obesity. By definition, obesity refers to a condition of building up of body fat
beyond that deemed normal for the age, sex, body type of a given individual. Obesity is not
only related with a number of health problems but with psychological problems also
(Wadden and Foster, 1992; NIH, 1992; Bray et al, 1996; Food and Drug Administration,
1996; Centers for Disease Control and Prevention, 1997; Connolly et al, 1997).
In scientific terms, obesity occurs when a person consumes more calories than he
or she burns. What causes this imbalance between calories in and calories out may differ
from one person to another? Genetically speaking obesity tends to run in families. This is
caused both by genes and shared by diet and lifestyle habits, environmental factor - the
most important environmental factor is lifestyle. The eating habits and activity level are
partly learnt from the people around the person. Overeating and sedentary habits
(inactivity) are the most important risk factors for obesity, psychological factor - in some
people, anxiety, worry, depression, love failures divorce, loneliness, unmarried, married
too late due to financial and other causes, unsuccessful in business, non-cooperation from
office colleagues or higher officials leads to emotional excitement, alcoholism, inactivity
or moody mentality and causes over eating mostly unnatural and tasty food to satisfy their
moods and other factors may all play a part. Excess body weight, especially when it is
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located in the abdominal region, has a strong association with blood glucose levels, insulin
resistance and the development of diabetes. This has been a consistent finding across a
range of prospective studies (Despres et al. 2001; Boyko et al. 2000; Njolstad et al. 1998;
Chan et al. 1994; Haffner et al. 1991; Charles et al. 1991; Colditz et al. 1990), crosssectional studies (Janssen et al, 2002; Schmidt et al, 1992; Dowse et al, 1991; Skarfors et
al, 1991) and recent reviews (Despres et al, 1990; Hodge et al, 1996; Kuller, 1999; WHO,
2000; WHO, 2003). A large number of studies support that central adiposity is the
dominant risk factor for the development of Type 2 diabetes, although there are some
exceptions. Perry et al. (1995) and Skarfors et al. (1991) found BMI was the dominant risk
factor over other measures of central adiposity for risk of developing Type 2 diabetes. A
review by Hodge et al (2001) concluded that both overall adiposity and central fat
distribution were important independent risk factors for Type 2 diabetes. Some illnesses
can also lead to obesity or a tendency to gain weight. These include hypothyroidism,
Cushing's syndrome, depression, and certain neurological problems that can lead to
overeating. Also, drugs such as steroids and some antidepressants may cause weight gain.
A medical person can tell whether there are underlying medical conditions that are causing
weight gain or making weight loss difficult. Obesity is of two types: localized and
generalized, localized mainly in the abdomen it is called as android obesity as male pattern
and when localized in hip region it is called gynoid obesity or female pattern (Pear
Shaped). In generalized fat is distributed all over the body without localized condition.
Numerous methods are used for weight reduction e.g. physical activity, dieting, surgery,
yoga and weight reduction pills and Electrical Muscle Stimulation (EMS).
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Physical activity is important for physical health, emotional well-being, and
achieving a healthy weight. Physical activity may help control the weight by using excess
calories that would otherwise be stored as fat. Most foods and many beverages one eats
and drink contain calories, and everything one does uses calories. This includes sleeping,
breathing, digesting food, and of course, moving around. Balancing the calories a person
ingests with the calories he use through physical activity may help maintain him current
weight. It may help in the control of body weight and prevent obesity, a major risk factor
for many diseases and it makes the person physically fit. Physical fitness is the ability of
the human body to function with vigor and alertness, without undue fatigue, and with
ample energy to engage in leisure activities, and to meet physical stresses. Muscular
strength and endurance, cardio respiratory integrity, and general alertness are the overt
signs of physical fitness. Physical fitness is usually measured in relation to functional
expectations-that is, typically, by periodic tests measuring strength, endurance, agility,
coordination, and flexibility. In addition, stress testing, which ascertains the body's
accommodation to powerful, sustained physical stimuli, is used to analyze fitness. If
individuals are able to accommodate to the stressors, they are assumed to be fit.
Obesity is the number one nutritional disorder in the developed world. According
to the most recent National Health and Nutrition Examination Survey (NHANES III, 19881994), between one-third and one-half of US men and women 20 years and older are
overweight, and nearly one-fourth are clinically obese. It is often a lifelong problem that
preferentially affects women (Dickerson, 2001). The information about the extent of
obesity in developing countries is needed in order to assist policy makers and health
planners with setting priorities, and for mobilizing and allocating resources to programs
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(World Health Organization, 1998). Much of the developing world still suffers from
nutritional deficiencies such as protein energy malnutrition, iron deficiency anemia,
vitamin A and iodine deficiencies (Administrative Committee on Coordination=SubCommittee on Nutrition, 1997).
A number of factors have been linked to obesity, including age, gender and
socioeconomic status. Patterns of prevalence of overweight and obesity have emerged
across different socio-economic groups. In developed countries levels of obesity are higher
in the lower socio-economic groups. In developing countries this relationship is reversed
Sobal and Stunkard (1989) after reviewing 144 published papers dealing with
socioeconomic status (SES) and obesity Found that in developed societies there was an
inverse Relationship between SES and obesity among women, i.e., the poor were more
likely to be obese. The relationship, however, was inconsistent among men and children of
both sexes. A different situation was observed in developing societies (which included data
from three native American populations – Apache, Kiowa/Comanche, and Navajo), where
the relationship was direct, i.e., the wealthy were more likely to be obese. This applied to
men, women and children.
In India it has been found that women from lower
socioeconomic groups are also significantly more likely to have a low BMI (Griffiths and
Bentley, 2001).
Clear gender differences are seen in most countries with more women than men
being obese (James et. al., 2000; Zargar et. al., 2000 Filozof et. al., 2001; Mokhtar et. al.,
2001;Ismail et. al., 2002). In contrast, the proportion of men who are overweight tends to
be greater than women. Research on obesity in India has found prevalence to be higher
among women (Misra et. al., 2001), and among economically better off persons (Singh et.
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al., 2000; Griffiths and Bentley, 2001) Higher socio-economic status has been consistently
associated with greater risk of obesity and diabetes, but the relationship with educational
status appears to be inconsistent (Gupta, 1994; al-Mannai et. al., 1996). In a study of
obesity among north Indian women it was found that women working as
professional/technical/managers were more prone to be overweight and obese than those
working in other fields (Agrawal, 2002). Age wise, a significant increase has also been
noticed for obesity. In developed countries it has been found that there occurs an increase
in the body weight with ageing, at least up to 50-60 years old (both in men and women).
The relationship between obesity and age is similar in developing countries, but the
maximum rates of obesity tend to be reached at an earlier age (e.g. 40 years old). The
decline in prevalence after this peak is thought to be partly attributed to lower survival
rates of obese individuals. In India, it has been found that older women were relatively
more overweight and obese than younger women (Agrawal, 2002).
There is substantial evidence that body weight is regulated by complex signaling
systems that provide afferent signals, including glucostatic, lipostatic, and aminostatic
signals to the CNS about the nutritional state of the organism, which are translated into
efferent signals that affect energy intake and expenditure (Rosenbaum & Liebel, 1998).
Benefits of Physical Activity/ Exercise
The benefits to physical activities are simply countless. The list overflows with
benefits that affect overall health and fitness, not only of the body but also of the mind.
Regular exercises help keep the body healthy, keeps mood relaxed, and protect from
chronic diseases. On the whole, exercise can improve performance in anything one does
and, in the long run, actually prolong the life. But one of the reasons that have got majority
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of exercise buffs dashing to the gym or to other exercise sessions is weight loss. Many
variables may influence eating behavior and therefore may also influence obesity,
including depression, anxiety, stress, social support, race, ethnicity, education and income
(Allen et al,2001; Goodman et al, 2002; Haas et al, 2003; Kaplan et al, 2003; Sammel et
al, 2003). While the national media and federal websites emphasize the importance of
physical activity in controlling body weight, exercise alone is not effective for this
purpose. In fact, some research shows no relationship between exercise and body weight in
community samples (Goodman et al, 2002). Belly fat reduction is the direct consequence
of physical exercises, dieting and lifestyle improvements. It results from changes in eating
habits, and it has a direct connection with emotional balance and positive thinking. A large
number of people suffer from overweight because of their personal dissatisfaction,
disappointments or failure in various aspects of their life.
Obesity has been thought to be a behavioral disorder that results from eating too
much and exercising less, these factors are associated with weight gain. Changes in the
lifestyle including the increased consumption of high fat foods, as well as increasingly
sedentary work and leisure habits, undoubtedly contribute to the marked rise in obesity.
Studies suggest that the body weight is under substantial genetic control, accounting for
approximately one third of the variation in BMI (Bouchard, 1997). Genetic influences
appear to contribute to differences among individuals in resting metabolic rate (Rice et al,
1996) as well as body fat distribution (Bouchard, 1998) and weight gain in response to
overfeeding (Bouchard et al, 1990). Some people appear to come into the world with a
predisposition to obesity, which is readily nourished by a high fat, low activity lifestyle.
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Energy Expenditure
For every physical activity, the body requires energy and the amount depends on
the duration and type of activity. Energy is measured in calories and is obtained from the
body stores or the food we eat (Davis, 1999). The measurement of the energy expenditure
of man depends on the following principle. All the energy used by the body in carrying
out either external work or internal work (such as the movements of the heart and
respiratory muscles, etc.), or in chemical synthesis (such as the production of enzymes in
the digestive juices or of hormones in the endocrine glands), or in maintaining the ionic
gradients between the fluids inside and outside the tissue cells, is ultimately degraded into
heat (Mccargar, et al, 1992, 1993; Robert, 1996). When measurements of total energy
expenditure are needed there are two requirements - first, an accurate account of all of the
time spent on each and every activity of the day by the subject. Second, it is necessary to
assess the metabolic cost of each activity. The energy expenditure is then calculated by
multiplying the time spent in each activity (min) by the metabolic cost of activity (Melby,
1989).
Role of Aerobic Exercises In Obesity & Benefits
Aerobic means "with oxygen" and aerobic exercise is defined as any long duration
exercise of low to moderate intensity using the large muscle groups of the body such as the
legs, back, gluteals, arms, etc. By long duration it is meant that in order to achieve the
many benefits of aerobic exercise, one must usually sustain this activity for 20 minutes or
longer. Activities that are very difficult or "intense" and can only be sustained for brief
periods of time (seconds to minutes), are usually anaerobic, or are carried out without
oxygen, and do not necessarily produce the same benefits as aerobic exercise.
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Aerobic exercises have large number of benefits. Aerobic activities strengthen the
heart and lungs, making them more efficient and durable, improving quality and quantity
of life (Fletcher et al, 1992). These include systemic changes such as reduced cholesterol
and blood pressure, improved muscular endurance, reduced body fat, increased
metabolism, to name a few (Sarkar et al, 2009). Exercise is known to not only extend the
life, but also give more energy to live it to the fullest. Aerobic exercise improves the
strength of the bones, ligaments and tendons, allows the body to use fats and sugars more
efficiently, burns lots of calories and plays an important role in reducing the onset and
symptoms of aging and illness (Sarkar et al, 2009). Aerobic exercise reduces the risk of
heart disease, vascular disease and diabetes. Aerobic exercise reduces stress and combats
depression as it raises self-esteem and physical awareness. Constant moderate intensity
works like bicycling riding, walking etc use up oxygen at a rate in which the cardio
respiratory system can replenish oxygen in the working muscles. It is a good activity for
fat loss when done in the right amounts but highly catabolic if done in excess. To prevent
weight regain after weight loss, it has been recommended that obesity can be treated with a
combination of physical exercise and reduced energy intake (Jakicic et al, 2001). Walking
is an aerobic exercise that is accessible to many segments of the population because it is
convenient, easy and low cost; because exercise intensity during walking is generally
below the lactate threshold, walking is considered a typical low-intensity exercise. Aerobic
dance, a popular exercise, particularly among women, is representative of moderate- to
vigorous-intensity exercise. Okura et al (2002) reported the various positive effects and
safety of combining aerobic dance with diet in the treatment of obesity.
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Leutholtz et al (1995) studied the effects of exercise intensity (40% vs. 60% of
heart-rate reserve) on body composition during energy restriction. Because these
investigators found that exercising at 60% of the heart-rate reserve was no better at
changing the body composition than exercising at 40% of the heart-rate reserve when the
total volume of exercise training was controlled, they concluded that exercise intensity did
not influence body composition changes. Three prospective studies without weight-loss
treatments (Manson et al, 2002; Tanasescu et al, 2002; Kraus et al, 2002) have
demonstrated the effects of exercise intensity on plasma lipoproteins, cardiovascular
events, CHD, and risk of type 2 diabetes. These studies, reported that exercise intensity
was associated with reduced risks (Manson et al, 2002; Tanasescu et al, 2002 ), and a
study by Kraus et al (2002) revealed that improvement in plasma lipoproteins were related
to the amount of physical activity and not to the exercise intensity. However, few details
have been reported on the effects of exercise intensity on improving CHD risk factors and
physical fitness during a weight-loss program.
Psychological Aspects of Obesity
Development of obesity has psychological bearing. Decreasing anxiety and
depression by physical exercise has become the most effective treatments to improve
mental and physical health. Indeed, the Foundations of Sport and Exercise Psychology
text states, “exercise is related to decreases in anxiety and depression as well as increased
feelings of general well-being” (Weinberg, 2007). In general research indicates that
individuals high in self-efficacy believe they can be successful in an activity, and
individuals high in self-esteem are more likely to engage and adhere to an exercise
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program which may help reduce anxiety and depression (Boyd et. al, 1997). Although the
focus of this argument is based on the powerful effects of exercise in improving the mental
state. The research reports show a correlation between high self-esteem and the probability
of engaging in and maintaining an exercise program (Baxter, 2010). Additionally, as the
cognitive processes of children have been categorized by age, the development of selfesteem also seems to be age-dependent and is impacted over time by social interaction and
personal experiences. Self-esteem impacts specific factors such as physical self-efficacy,
self-confidence, anxiety, and perceived control in both male and female athletes of all ages
and across different sports disciplines. An individual’s participation in sports tends to be
related to these factors (Boyd et. al, 1997). Additionally, research performed by Gauvin
and Spence (1996) indicates that exercise adherers report higher levels of efficacy beliefs
about their ability to adhere to exercise as well as their physical proficiency in exercise
activities (Gauvin et. al., 1996). This research paired with Boyd’s indicates that not only
does participation in exercise activities help to increase self-esteem, but as self-esteem
increases the likelihood of continued participation in exercise that provides many health
benefits also increases. In contrast, research performed with adolescents who possessed
low self-esteem showed tendencies to under-eating and over-eating with less likelihood of
adherence to physical activity (Mueller et. al., 1995). These two opposing studies support
both lack of participation in physical activity reduces self-esteem while participation in
physical activity increases it. Low self-esteem has been implicated in most psychological
dysfunctions. However, it appears that low self-esteem is not necessarily the root cause of
this dysfunction. It is believed that individuals with high self-esteem who may be
predisposed to psychological disorders are better equipped to cope with those disorders,
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and thus, reduce the negative consequences that may result (Aro, 1994). From this
perspective, one could ascertain that if self-esteem can be enhanced, then the psychological
consequences of disorders can be reduced. This concept supports the argument that
exercise is in the position of being able to contribute to the prevention of illness or the
reduction of its effects through the process of improving self-esteem. The study conducted
by (Koniak-Griffin, 1994) at UCLA further support this claim.
The most unattractive conditions: cellulite, fat and flabby tissue, are without doubt
the most common for women over 30 years of age. This result in progressive atrophy of
the muscles in the affected area due to the accumulation of fat, which completely
encapsulates the muscular abdomen, causing the alterations in the circulation, with an
actual hypoxia of the muscles. The muscle shrinks further and further, it deflates, so to
speak, leaving room for the fatty capsule, which surrounds it and increases evermore in
size and consistency. If obesity is linked with medical conditions, the site of the body,
which carries more fat, matters and is associated with diseases. For example, out of two
types of obesities, android obesity (more fat deposition in the upper body regions like trunk
and abdomen) is more harmful than gynoid obesity (more fat in hip and thighs). Exercise
experts and health educationists put more emphasis on increased physical activity in the
form of exercise to counter obesity. The major types of exercise programs widely practiced
involve aerobics, weight training programs and a combination of aerobics and weight
training (Katzel et al, 1995; Pate et al, 1995; NIH, 1996). These exercise programs are
usually effective in countering milder forms of obesity and purposive in the sense that
improvement or maintenance of physical fitness is an objective. However, weight loss
achieved by these techniques is slow and of lower magnitude.
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Use of Electronic Muscle Stimulation (EMS) In Weight Reduction
Electronic Muscle Stimulation (EMS) is a technique of application of externally
produced impulses via electrodes, causing the contractions in muscles. This technique
finds many uses including weight loss, rehabilitation, and body building, and training
technique of athletes. Various electrotherapy modalities e.g. ultrasound, short wave
diathermy and interferential therapy are also used by the health and obesity clinics world
over to counter obesity (Anderson & Wadden, 1999; Klein, 2000; Jakicic et al, 2001).
These clinics are commercially exploiting the people by assuring them fast fat reductions.
It is claimed by these professionals that Electrical Muscle Stimulation (EMS) leads to
faster and greater weight loss from the fat compartments of the body. The scientific
validity of such claims direly needs to be ascertained. Electrical stimulation is effectively
used in physiotherapy clinics to provide a situation whereby there is an electrical
generation of action potentials; giving rise to therapeutically significant physiological
responses e.g. increased muscle strength, stimulated lymph and blood flow, analgesia,
kinesthetic awareness and autonomic nervous system responses. It is believed by these
clinics that EMS initially breaks the fatty capsule that covers the muscle, improves blood
supply to the muscles, and then helps it to gain the lost tone to return to its original size.
This return to size and tone gives the abdominal muscles the strength to crumble the fatty
capsule from the inside, through their contractions (Bailey, 1976). There are four different
types of electrical muscle stimulations. These are regular EMS, transdermal electrical
neural stimulation (TENS), interferential (IFT) and Russian muscle stimulation. Out of
these, IFT has the ability to stimulate (a) large number of muscle fibers for greater
muscular work (b) parasympathetic nerve fibers for causing increased blood flow in the
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region and (c) deeper tissues at the stimulated sites. According to Gersh (1992); Hayes
(2000) and Prentice (2001) neuromuscular electrical stimulation improves increases
metabolic demand through activating the muscle pump around the circulation network.
They recommend that a low frequency of 20-30 pps with 10- 30% of maximal effort up to
10- 30 minutes duration is most effective. Interference current, utilized as interferential
current therapy (IFC), is based on the summation of two alternating-current signals of
slightly different frequencies. This results in current having a recurring modulation of
amplitude, based on the difference in frequency between the two signals. When these
signals are in phase, they sum to amplitude sufficient to stimulate; when the signals are out
of phase, no stimulation occurs. Interferential current therapy can deliver high currents
compared to other stimulators, and can use 2, 4, or 6 applicators, arranged in either the
same plane for use on regions such as the back or in different planes in complex regions
such as the shoulder (Gersh,1992; eMedicine Clinical Knowledge Base, 1996). Electrical
stimulation affects each phase of wound healing differently, by increasing blood flow that
can help in the removal of debris by way of phagocytosis; in addition, by increasing blood
flow, electrical stimulation enhances tissue oxygenation. Neuromuscular electrical
stimulation (NMES) has been commonly used in physical therapy and rehabilitation to
help patients facilitate peripheral circulation, increase muscle power and endurance, and
re-educate motor function (Lake et al, 1992; Alon et al, 2008). At the point of health
promotion it is gaining significant attention, NMES is introduced to increase physical
fitness and reduce the risk of heart disease. Clinically, NMES is provided as an alternative
to more conventional forms of exercise to encourage increases in physical activity. This is
especially true in the case of those who are unable to engage in physical exercise or have
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barriers to participation, such as individuals with stroke or spinal cord injury (SCI). NMES
has been used to help individuals with SCI exercise or passively move their extremities
and is found to significantly improve their aerobic capacity (Raymond et al, 1997; Griffin
et al, 2009). Other identified health benefits of using NMES in promoting exercise have
been reported and includes improvement in muscle strength/endurance, enhanced
peripheral circulation, attenuated bone mineral density loss, improved body composition,
more efficient and safer cardiac function, and cardiovascular, and pulmonary training
adaptations ( Lai et al, 2010; Sabut et al, 2010).
In addition to helping in promoting exercise, another common application of
NMES is associated with burning fat in that NMES is given on unloaded muscles, i.e.,
without loading limbs or joints when an individual is at rest. Commercially, it is claimed to
be able to facilitate fat burning and has been used to serve as part of weight loss/control
programs. It is assumed that NMES can enhance energy consuming, considering that
NMES induces muscle contraction and increase fat utilization. It is thus pertinent to
explore the EMS through interferential currents to counter the problem of overweight in
the people. In this context the present study has been undertaken on females ranging in age
from 20– 40 years to explore the impact of EMS-Interferential program on weight loss as
well as the shedding of fat from the abdominal region, so as to reduce the health risks.
Objectives Of The Study
1. To study the effect of four weeks of electrical muscle stimulation by
Interferential mode on the abdominal region on the thickness of abdominal
skinfold.
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2. To study whether the application of hot water on the abdominal area affects the
ability of EMS (IFT) to reduce fat.
3. To compare the effects of aerobic exercise program with the effects observed
by electrically stimulating the muscles through Interferential electrical muscle
stimulation.
Hypothesis
The present study endeavours to test the affectivity of electrical muscle stimulation
in reducing fat from the specific body sites. The study is based on the hypothesis that
Interferential current stimulation (EMS) because of its known ability to (a) stimulate large
number of muscle fibers for greater muscular work (b) cause increased blood flow through
parasympathetic nerve fibers in the region and (c) stimulate deeper tissues will be effective
in loss of fat from the stimulated sites.
In addition, the study is also likely to reveal the supportive effect of increasing
blood circulation (through hot water bottle application) on the ability of fat reduction by
EMS (IFT). If the EMS is found to be effective in reducing fat; then the potential can be
exploited to reduce the obesity related disease burden in the society.
Inclusion Criteria
Only the females in the age range of 20-40 years having BMI > 27 was included in
Study
Exclusion Criteria
The female who are wearing any metallic device in the abdomen was excluded
from the study
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