EFFECTS OF DIFFERENT INTENSITY LEVELS OF CIRCUIT RESISTANCE TRAINING ON PHYSIOLOGICAL VARIABLES OF YOUNG FEMALE ADULTS IN PLATEAU STATE, NIGERIA

Abstract

The purpose of this study was to determine the effects of different intensities of circuit resistance training on body composition, resting blood pressure and resting metabolic rate of young female adults in Plateau state. A pre-test and post-test group research design was used for the study. Thirty (30) young female adult volunteers were randomly assigned into three groups of low, moderate and high intensity to 12 weeks of circuit resistance training (CRT) (LI, n=10, 29.7+3.04; MI, n=10, 28.6+2.12; HI, n=10, 29.3+2.43 years). The low intensity group exercised at 40% 1 repetition maximum while the moderate and high intensity exercised at 50 – 60% 1 repetition maximum. The exercise was conducted 3 times a week and 30 – 40 minutes per session. The variables measured were percent body fat (%BF), waist-to-hip ratio (WHR), lean body mass (LBM), resting systolic blood pressure (SBP), resting diastolic blood pressures (DBP), and resting metabolic rate (RMR). At the end of the 12-week training period, there was a decrease (p<.05) in the three CRT groups %BF (LI = – 1.8%; MI = -2.4%; MI = -2.9%, (BP) LI = – 6/3, MI = -7/5, HI = -9/6, an increase in LBM (LI = 1.2kg; MI = 3.8kg; HI = 5.1kg), RMR (LI = 34; MI = 81; HI = 112). One way analysis of variance (ANOVA 1) and Scheffe’s post hoc tests were used to find out the significance effects on the physiological variables of the participants. And the F-value of %BF, WHR, BMI, LBW, SBP, DBP and RMR were 20.78, 17.23, 2.58, 5.23, 4.25, 4.75 and 5.16 compared to critical value of 2.37 respectively. The results of the study revealed that the different intensities CRT had significant effects on body composition, resting blood pressure and resting metabolic rate of the participants. On the basis of these findings, it was recommended that: young female adults should train more at moderate or relatively high intensity circuit resistance programme. This would go a long way to generally improve their health and fitness.

CHAPTER ONE:

INTRODUCTION

Background of the Study

Circuit resistance training (CRT) is a great type of training routine that offers a number of benefits, especially for those who have a limited time for workout. Circuit resistance training is the practice of doing exercises with resistance and moving simultaneously from one station to the next with no real break in between exercise. It can be designed to increase muscular strength and power, muscular endurance, flexibility and to a limited extent, cardio-respiratory endurance. However, the physiological effects depend to a large extent on the type of circuit that is set up. For example, a circuit consisting only of weight-resistance exercises produce substantial gains in strength but only minimal gains in cardio-respiratory endurance (Gettman, Ayres, Pollock, and Jackson, 1978; Wilmore,Parr, Girandola, Ward, Vodak, Barstow, Pipes, Romero, and Laslie, 1978).

The physiological effects of circuit resistance training (CRT) onbody composition, resting blood pressure, and resting metabolic rate (RMR) of females have been of great interest to exercise scientists, dieticians, clinicians, coaches, allied sports and health professionals. Since early times, different kind of training programmes that may also be effective in improving health and fitness in females is the circuit resistance training (CRT). Corbin and Lindsey (1994), defined circuit resistance training as a routine of selected weight exercises or activities performed as possible in a sequence at circuitous individual stations.

In recent times, circuit resistance training (CRT) has become a popular and standard practice in research studies and a means to improve health and fitness profiles of females over the course of training. Thus, circuit resistance training is one of the training methods used to improve health and fitness.

Circuit resistance training is being favored by some fitness specialists and coaches in the training and conditioning of athletes and non-athletes, to improve their health and fitness.

Body composition is of great interest to coaches and athletes. Body size influences physical performance in many sports, health and fitness and appearance in women. Body composition consists of absolute and relative amounts of muscle, bone, fat tissues, water, minerals and other components of total body mass (Heyward, 1991). Researchers, in general, refer to body composition in terms of fat percentage (%BF), fat mass (FM) and fat free mass (FFM), with fat free mass as body structures excluding fat mass (Wilmore and Costill, 1994). Weight and body composition are directly related to energy balance. Energy balance is influenced by expenditure from physical activity, recreational and occupational exercises (Heyward, 1991; Jakicic and Otto, 2006). Studies suggest that regular exercise has positive effect on body weight, body composition and aging (Aderson&Jakicic, 2009; Heyward, 1991).A variety of exercise modes benefits body composition, improves health, and enhance exercise performance. Resistance training helps build fat-free mass as well as promoting positive changes in body composition (Ucan, 2013)

Body composition is an important component of physical fitness (Hagsromer, 2007). Body composition is divided into fat mass and fat free mass of the body (Hoeger, 1998, 2002;Musa, Lawal and Sarkinfawa, 2001). And that body fat increases with decreases in lean body mass. The focus of this study, is to find out whether body fat decreases and lean body mass is enhanced. Many young female adults today are very seriously concerned with their weight as most of them are overweight and obese. There has been, therefore, a growing caloric anxiety around the world as thin standards of beauty and fat ways of living are emerging. People accumulate fat mass when their caloric intake is higher than their caloric expenditure, although a lot of factors like genetics, metabolism, culture, and lifestyle confound the picture. This is understandable as overweight and obesity constitute a very serious health problem. Exercise appears to play a critical role in body weight control management (Kraemer, Volek, and Clerk, 1999). It’s important to consider the duration, intensity, and type of exercise (especially CRT) that should be recommended for weight loss.

It is more important to consider the way in which fat is distributed in the body than the total body fat to determine the risk of disease. Abdominal fat has been shownto be very closely associated with disease risk like coronary heart disease, hypertension and diabetes. Similarly, the waist-to-hip ratio (WHR) is closely associated with visceral fat. The influence of regional fat distribution on health is related to the amount of visceral fat present in the abdominal cavity (Venkateswarlu, 2011).Regional fat distribution is usually determined in a field setting by using the WHR and young female adults with WHR values of more than 0.85 are at greater risks of health hazards (Skinner, 2005).

Overweight and obese young female adults are at greater risk of cardio vascular disease, hypertension, diabetes, cancer, etc.Venkateswarlu (2011), explained that blood pressure is the forced exerted by blood against the walls of the blood vessel. The pressure is exerted as the blood is carried from the heart to all part of the body in blood vessel. Blood pressure is highest when heart contract during which the blood is pumped into the vessel called arteries. The force is cause by the pumping action of the heart through the arteries (McGlynn, 1999; Katch,McArdle and Katch, 1999). High blood pressure is a killer disease because it does not give any early warning. It increases the risk of heart diseases, stroke and kidney failure (Venkateswarlu, 2011). Furthermore, a resting metabolic rate (RMR) is the rate at which the human body expended calories in order to maintain normal body processes in a resting state. It measures the number of calories the body requires to maintain itself at rest and it varies with body composition.RMR constitutes approximately 67% of the total body calories expenditure. The remainder of calories expended is through physical activity (23%) and thermal effect of food (10%) (Nieman, 2007), since RMR constitutes such large proportion of the constant amount of energy expended, a potential long term increase could significantly help overweight young female adultsto lose fat mass (FM). A strong correlation existed between RMR and a person’s amount of fat free mass (FFM)(Byrne and Wilmore, 2001b). FFM includes the composition of the body muscle, bone, organ, and connective tissue. One of the most efficient ways of increasing FFM is through circuit resistance training. However, studies show that CRT raises RMR significantly more than aerobic training (Dolezal and Potteiger, 1998; Byrne and Wilmore, 2001b).

Although most research studies have examined the effect of endurance exercise on weight loss, CRT has recently become an important component of a successful weight loss programme by helping to preserve FFM and maximizing fat loss (Osterberg&Melby, 2000). Therefore, it is hypothesized that CRT can increase a person’s RMR and improve the rate at which FM is lost during exercise and at rest.

RMR is affected not only by body size and age but also by body composition. Muscular individuals have higher RMR than obese individuals of the same weight. This is mainly because fat tissue is less metabolically active than muscle tissue (Venkateswarlu, 2011). Many people today are engaged in doing things that do not increase energy expenditure, and this may be related to all – mortality such as low quality of life and higher risk of obesity, cardiovascular diseases, low back pain, diabetes and cancer. People accumulate fat mass when their caloric intake is higher than their caloric expenditure. Therefore, the aim of this study was to investigate the effects of different intensities CRT body composition, resting blood pressures and resting metabolic rate of young female adults.

1.1 Statement of Problem

Recent studies as well as a recent report in time magazine (2010) have shown convincingly that aerobic centered exercise provides little advantage in creating real body change. The benefit of exercise are well established but one major barrier for many is time. It has been proposed that short period resistance training could play a role in weight control by increasing resting energy expenditure but the effects if different intensities has not been widely reported.

Circuit resistance training has often been overlooked as a treatment for hypertension, primarily because it is known to elevate diastolic blood pressure during the circuit resistance exercise. However, recent review found that resistance training does not raise blood pressure level significantly (Kelley and Kelley, 2000). It was also reported that circuit resistance training, rather than the traditional repetition strength training, led to a greater reductions in blood pressure. This was likely to be due to the greater number of repetitions and reduced recovery utilized with circuit resistance training. Therefore, there is likely to be greater cardiovascular component to circuit resistance training.

However, there are controversies over whether high, moderate or low intensity exercise is more important for stimulating a decrease in body fat content and blood pressure. But lower exercise intensities work better at reducing blood pressure than higher intensities (Hagberg, Park and Brown, 2000).

Interest has surged in the use of CRT for improving general health and fitness. There is a relationship between body composition, blood pressure and resting metabolic rate. Resting metabolic rate can be influence by body composition (percent body fat and fat-free weight. The variability in RMR is predicted by fat-free mass (Kim and Park, 2003). Also body composition can influence blood pressure.

Unfortunately, findings are not always consistent, and this is likely attributable to differences in training programmes used in different studies, the volume and intensity of the training, the rest interval between the exercises and sets, and the selection of exercise stations can greatly influence the results of any circuit resistance training programme.

Despite decades of research into the effects of CRT on fat metabolism, there is still no clear understanding on how exercise helps to regulate FM. Although, exercise can improves the capacity of muscle to oxidize fat, which can lead to weight reduction. This study therefore, is to investigate the effect of different intensity levels of CRT programme has on fat oxidation.

The effects of CRT on blood pressure are varied due largely to differences in study design and exercise intensity which suggests that more research is necessary to clearly understand the role of CRT in blood pressure and weight management. Unfortunately, because of conflicting studies, the effects of different intensity levels of CRT on body composition, blood pressure, and RMR in young female adults is still unclear. Therefore, the thrust of this study is to find outthe effects ofdifferent intensity levels of CRT on body composition, blood pressure, and RMR in young female adults.

1.3         Research Questions

In the light of the purpose of the study, the following research questions were raised for this study:

1. What are the effects ofdifferent intensity levels of CRT on body composition of young adult female adults?
2. What are the effects of different intensity levels of CRT on resting blood pressure of young adult female adults?
3. What are the effects of different intensity levels of CRT on resting metabolic rate of young adult female adults?

1.4 Purpose of the Study

The main purpose of this study was to determine the physiological effects of different intensity levels of CRT on body composition, resting blood pressure, and resting metabolic rate in young females in PlateauState. Therefore, the thrust of this study was to determine the effects of different intensity levels of CRT on body composition, blood pressure, and RMR inyoung females in Plateau State.

This training programme will be more time effective by alternating two or more resistance exercises that subjects worked different muscle groups of body parts (upper body, trunk and lower body) alternately called circuit resistance training. This CRT programme for women was designed to achieve desired curves such as tone arms, narrow waist and proportioned hips. CRT programme for women emphasize the lower body because women store fat in the hips and thigh, while working on the upper body tone arms and sculpts the torso. The programme also targets the abdominal region where fat is also accumulated.

Specifically, this study was to assessed and compare:

1. Theeffects of different intensity levels ofCRT on body composition ofyoung female adults.
2. The effects of different intensity levels of CRT on blood pressure ofyoung female adults.
3. The effects of different intensity levels of CRT on resting metabolic rate of young female adults.

1.5         Hypotheses

For the purpose of this investigation, the following null hypotheses were formulated and tested.

Major hypothesis

There are no significant effects of different intensity levels of circuit resistance training on body composition, resting blood pressure and resting metabolic rate  young females in Plateau State.

Sub-hypotheses

1. There is no significant effects of different intensity levels of circuit resistance training on body composition of adult young females in Plateau State.
2. There is no significant effects of different intensity levels of circuit resistance training on blood pressure of adult young females in Plateau State.
3. There is no significant effects of different intensity levels of circuit resistance training on resting metabolic rate of adult young females in Plateau State.

1.6         Significance of the Study

The present study was designed to determine the effects of different intensity levels of circuit resistance training on body composition, resting blood pressure and resting metabolic rate of young females in Plateau State.

This research would be of great significance in the field of sport medicine, education, health, sports, engineering and economic of our dynamic society. The results would be beneficialto coaches, physical educators, exercise and sports scientists, physical fitness specialists, health professionals as well as females interested in circuit resistance training programmes with the knowledge and skills required to successfully plan such programmes.

This study would serve students of exercise and sport science, physical and health educationists and other related field as reference guide in creating CRT programmes. It wouldbe of help to students taking exercise and sport science and other related courses to identify the best training method to use. Fitness and exercise specialists found the information on CRT useful in sensitizing women on fitness issues. The result on this CRT programme would aid women in making informed decisions on fitness and weight reduction issues. Young femaleswith well informed decisions would promote their fitness and health status, the fitness of their families and that of the community in general.

The study would also be of help to physical and health education teachers to have deeper understanding of CRT. By this study, teachers, fitness instructors, coaches, exercise and sport science specialist would come up with easier and more powerful programmes to improve health, fitness and sport performance. The study would be of great help for females who have tight schedule and may be able to dedicate their time for this short duration exercise, thereby producing significant improvement and greater adherence to training programme for health and fitness. The results of this study unveiled those resistance exercise beliefs by females that had over the years, subjected females to health and fitness disadvantage as females have always been victim of cultural and traditional ways of life beliefs. Exposure to such training would influence young females to resist those “old life’s tale”(beliefs that cannot be proved scientifically) that negatively affect their health and fitness and imbibe acceptable fitness exercises that would promote the body health and fitness. In the same vein, the outcome of the study would aid young females to take informed decisions against fallacious beliefs about CRT exercise during their fitness programme, as most of these beliefs are “old fashion” and cannot be authenticated.

The result of the study added to the pool of existing researches, and serve as reference materials for exercise specialists, fitness instructors, physical educators and health educators when they are planning workshops or seminars for their clients. The study would also benefit and help future researchers as their guide. It can also open in development of this study.

1.7         Delimitation of the Study

The study was conducted in KatonRikkos community in Jos metropolis of PlateauState. The researchfocused on the effects of different intensities CRT programmes on body composition, resting blood pressure, and resting metabolic rate of young females adults between the ages; 18 to 35 years who’s BMI were between 25.0 and 29.9 kg/m²of adult females in Plateau State. The research was conducted in a fitness gym where the equipment and space for indoor were available. The research period lasted for twelve (12) weeks. The research was also limited to the effects of low, moderate and high intensity levels of CRT on percent body fat, waist circumference, hip circumference, waist-to-hip ratio, lean body weight, resting blood pressure and resting metabolic rate of young females in Plateau State.

1:8 Limitations of the Study

In this study the researcher did not have control on the climatic condition and other family affairs. The subjects’ previous physical activity was not controlled. Therefore, the researcher did not actually have the knowledge of what type of physical activity the subjects were participating prior to the training programmes. The subjects were recruited only within PlateauState.

The researcher did not have control on the diet of the subjects. However, since they live in the same climatic environment and of similar socio-economic status, it was assumed that their diets were similar. There was no personalized nutritional guideline to the participants.

1. Subjects were recruited from KatonRikkos community in Jos metropolis. The subjects of this study were volunteers and therefore were already motivated and looking for exercise benefits. This type of self-motivated individual may not truly represent the entire population.
2. Bias also existed in the sampling. There was geographical bias due to subjects selected were all young female adults and from KatonRikkos community in Jos metropolis.
3. The research was conducted on young female adults which lasted for 12 weeks. The 12 weeks was not enough for the researcher to observe all the physiological effects on their body. It would be better if was done in a longer time.
4. The number of the subjects decreased as the research progressed, as a result of lack of commitment and dropout, this made the population of the experimental group small.
5. The instruments used for the measurements might not provide accurate information because of some mechanical, technical or human error, weather condition, psychological factors and other magnetic materials.
6. It was unavoidable that in the process of this study, certain decree of subjectivity could be found. It would have been a sort of more objectivity if it was measured by more experienced technicians