Physical fitness is the ability to carry out daily tasks with vigor and alertness without undue fatigue and ample energy to enjoy leisure time pursuits and meet unforeseen emergencies. (Presidents Council on Physical Fitness and Sport)
??Physical fitness is the ability of the heart, blood vessels, lungs and muscles to perform at optimal efficiency.?? (Bud Getchell, PhD)
??Physical fitness is the ability to perform moderate to vigorous levels of physical activity without undue fatigue and the capability of maintaining such ability throughout life.?? (American College of Sport Medicine)
??Physical fitness is a set of attributes that people have or achieve that relates to the ability to perform physical activity.?? (U.S. Centers for Disease Control and Prevention)
Definitions with vague, subjective wordings and definitions made up of terms that also need defining led to confusion and lack of ability for objective measurement of physical fitness. There are other numerous definitions of physical fitness which are vague and subjective as pointed by the below statement;
??Physical fitness is one of the most poor defined and most frequently misused terms in the English Language.?? (Brian Sharkey, PhD, professor emeritus of Montana State University)
To enable objective measurement of physical fitness, it is divided into two components; health-related components of physical fitness and athletic ability components of physical fitness. The later components are related to performance or skill.
Figure X: Components of physical fitness (ACSM, 2008).
From the public health perspective, health related physical fitness are more important than those related to athletic ability or are skill-related or performance related components. The assessment of health related physical fitness is commonly done by fitness professionals, however, despite the recognized importance of health related physical fitness, it is not commonly assessed by clinicians(ACSM, 2008).
As illustrated in figure X below, all health-related components of physical fitness contribute equally and in balance to the whole construct of health related physical fitness.
Figure X: A balance between all five components to the construct of health related physical fitness (ACSM, 2008).
a. Cardiorespiratory fitness
Cardiorespiratory fitness is related to the ability of a person to perform large muscle, dynamic, moderate to high intensity exercise for prolong periods and can be assessed by various techniques. Cardiorespiratory fitness of a person reflects the functional capability of the heart, blood vessels, blood, lungs and relevant muscles during various types of exercise demands. It is related to the ability to perform large muscle, dynamic, moderate-to-high intensity exercise for prolonged periods.
There are many methods available to measure or predict cardiorespiratory fitness. Those methods fall into three general types of assessment which are;
i. Field test.
These tests generally demand maximal effort for the best score. For this type of test, the subjects have to perform a timed completion of a certain distance, complete a measured distance, or perform for a set time to predict cardiorespiratory fitness. Examples of field tests modes include walk, walk-run, cycle, swim and others.
ii. Submaximal exertion test.
This type of test require using either step test or a single-stage or a multi-stage submaximal exercise protocol to predict maximal aerobic capacity or cardiorespiratory fitness from submaximal measures of efficiency of certain measured variables (usually heart rate response). Some modes of submaximal exertion tests include steps, treadmill, cycle and others. Many of these tests required to be performed in a laboratory setting.
iii. Maximal exertion test
Maximal exertion test use a graded or progressive exercise test to measure an individual??s volitional fatigue or exhaustion which involves a measure of cardiorespiratory fitness rather than prediction and is likely performed in a laboratory setting.
Maximal exertion test along with collection of expired gases is considered as a true measurement of cardiorespiratory fitness however it is desirable in many setting. Decision of which test to be use depends on;
* Time demands
* Expenses or costs
* Personnel needed (qualification)
* Equipment or facilities needed
* Physician supervision needed
* Population tested (safety concern)
* Need for accuracy of data
Flexibility in health related physical fitness is defined as the ability of a person to move a joint through its complete range of movement. Flexibility is not joint specific as it is dependent upon which muscle and joint being evaluated. Other factors effecting flexibility includes distensibility of the joint capsule, adequate warm up, muscle viscocity and compliance of ligaments and tendons. Flexibility assessment is necessary because of the recognized association between decreased performances of activities of daily living with inadequate flexibility. Development of muscular lower back pain may be contributed by poor lower back hip flexibility. In reality, there??s no single test that can used to truly characterize a person??s flexibility. The most widely used test for the assessment of flexibility is the sit and reach test. Even though it does not represent the whole body flexibility, it does represent hamstring, hip and lower back flexibility.
c. Muscular strength
Muscular strength in health related physical fitness refers to the maximal force that can be generated by a specific muscle or muscle group.
d. Muscular endurance
Muscular endurance refers to the ability of a muscle group to execute repeated contractions over a period of time sufficient to cause muscular fatigue, or to maintain a specific percentage of the maximum voluntary contraction for a prolong period of time.
Cardiovascular diseases risk (National Vascular Disease Prevention Alliance, 2009);
1. Modifiable risk
a. Lifestyle related
ii. Physical activity level
iii. Smoking status
iv. Alcohol intake
b. Metabolic risk
i. Blood pressure
ii. Waist circumference and body mass index
iii. Serum lipid
iv. Blood sugar
2. Non modifiable risk
c. Family history of premature CVD
d. Social history (cultural identity, ethnicity, socioeconomic status, mental health)
a. Health related physical fitness
a. Cardiovascular endurance
b. muscle endurance
c. muscle strength
JUSTIFICATION OF STUDY
1. General objectives
To compare the effect of light resistance training using light dumbbells and ankle-wrist weights on body composition, metabolic risk and health related physical fitness level.
2. Specific objectives
i. To determine and compare the effect of light resistance training between using dumbbells and using ankle-wrist weights in term of changes in body composition;
a. Body mass index
b. Waist circumference
c. Waist to hip ratio
d. Percentage in body fat
e. Fat free mass
ii. To determine and compare the effect of light resistance training between using dumbbells and using ankle-wrist weights in term of metabolic risks;
a. Blood pressure
i. Total cholesterol
v. Total cholesterol/HDL-C ratio
c. Fasting blood sugar
iii. To determine and compare the effect of light resistance training between using dumbbells and using ankle-wrist weights in term of other components of health related physical fitness;
a. Cardiorespiratory fitness
c. Muscular endurance
d. Muscular strength
3. Research questions
Does light resistance training using dumbbells have a similar significant beneficial effects compared to light resistance training using ankle-wrist weights.
4. Study hypothesis
Both types of light resistance training; using dumbbells or using ankle-wrist weights does have beneficial effects in term of improvement in body composition, reducing metabolic risk and improving health related physical fitness level.
Tumpat is a district (jajahan) in Kelantan, situated at the East Coast of peninsular Malaysia. The town of Tumpat is approximately 15km from the state capital, Kota Bharu. Tumpat district has an area of 169.5 square kilometres is one of the smallest district in Kelantan (Tumpat District Council, 2012). Total population of Tumpat district in 2010 was 143,793 with the majority being the Malays (130,922 or 91.0%). Other ethnic groups include Chinese (6,227 or 4.8%), Siamese (4,784 or 3.7%) and Indians (121 or less than 1.0%). Tumpat district is divided into seven subdistrict (mukim) which is Jal Besar, Kebakat, Pengkalan Kubor, Sungai Pinang, Terbok, Tumpat and Wakaf Bharu (Department of Statistics Malaysia, 2010b, Department of Statistics Malaysia, 2010a).
1. Study design
This is a single-centred, randomized parallel group trial.
2. Reference population
The inference population for this study were Malaysian adults
3. Target population
The target population were Malaysian overweight and obese adults
4. Source population
The source population for this study were all adults living in Tumpat Districts.
5. Sampling frame
Overweight and obese adults living in Tumpat District were recruited for this study.
i. Inclusion criteria
a. Aged equal or more than 18 years old at the time of recruitment.
b. Body mass index of equal or more than 23 kg/m2.
ii. Exclusion criteria
b. On any weight management treatment/program
i. Taking any medication which the primary intention is to reduce weight
ii. Taking any traditional medication which the primary intention os to reduce weight
iii. On any dietary modification for weight management
c. Existing joint pain which restrict physical movement
d. Existing cardiac condition which restricted physical activity i.e.: a person with NYHA Functional capacity class II, III and IV (American Heart Association, 2011)
7. Sample Size determination
Number of subjects required for this study were calculated using sample size calculation for test of means with repeated measures in STATA software (StataCorp., 2011). With power of study (1-?) set at 80% and ? set at 0.05, summary of sample size calculated were as table X below;
Table X: summary of sample size calculation
8. Sampling techniques
All eligible and consented subjects were included in this study.
9. Randomization techniques
Subjects were randomized into 2 treatment groups; light resistance training using dumbbell and light resistance training using ankle-wrist weights using RandomAllocation Software version 1.0 (Saghaei, 2004).
No blinding methods were applied in this study. Both participants and observer know group allocation.
11. Study time and duration
This study was conducted for 6 months beginning from March 2012 until August 2012.
* Both groups will receive health education of promotion of healthy lifestyle which includes promotion of healthy diet, encouraging physical activity and benefits of not smoking.
* Resistance training:
i. Dumbbell exercise.
In this group, participants performed dumbbell exercise with a pair of light weight (1kg) soft dumbbells for at least 15 minutes per day, three non consecutive days per week using dumbbell exercise method invented by Professor Suzuki Masashige, Bull Inst. Health & Sport Science, University of Tsukuba (Suzuki, 2000). Supervised group exercises were conducted for 3 months and after that, the subjects will be required to do the exercise on their own. Subjects were given a diary to write the date and duration of training they perform. During weekly follow up, adherence to exercise was assessed. Subjects who did not adhere to minimal requirement of training will be excluded from the study. Non adherence was defined as a participant who performs the training less than 80% of required frequency and duration (less than 9 times per month). Figure X below illustrates the resistance training using soft dumbbells with sets of movement as below. This dumbbell exercise consists of 12 steps with 12 repetitions using a pair of soft light weight dumbbell.
Step 1: push up motion
Step 2: pull down motion
Step 3: the leg bends
Step 4: Upper body twists left and right movement
Step 5: double doors closing movement
Step 6: opening and closing movement forward tilt swing
Step 7: winding down motion with both hands
Step 8: winding down with one hand movement
Step 9: pulling down with one hand movement
Step 10: hand down the back swing movement
Step 11: arms swing down forward movement
Step 12: bending arms stretched behind the head movement
Figure X: 12 steps of dumbbell exercise using sandbags.
ii. Resistance training using ankle and wrist weights.
This group of subjects was not given any specific exercise regime. They were given a pair of 0.5 kg ankle and pair of 0.5kg wrist weights and they were instructed to wear them for at least 15 minutes 3 non consecutive days per week during activities of daily living which involves movements of upper and lower limbs such as walking, doing house chores or gardening. Subjects will be given a diary to write the date and duration of training they perform. Adherence to the training was assessed every week. Non adherence was define as a participant who perform the training less than 80% of required frequency and duration (less than 9 times per month) and those who did not meet minimal requirement of the training were excluded from the study.
13. Tools and materials
a. Data collection sheet
A data collection sheet was used to obtain demography data of the subjects;
b. Anthropometry measurements
Anthropometric measurement was assessed by a team of trained personnel. Measurements as below were obtained.
Measurement of height was done using a stadiometer. With shoes removed, standing straight up and looking straight ahead, the subject take a deep breath and hold. The height was recorded in centimetres to the nearest 0.5cm (ACSM, 2008).
ii. Waist circumference
The waist circumference was measured using a non elastic measuring tape with the subject stand straight and relaxed. Measurement was taken 2.5 cm (1 inch) above the umbilicus and below the xiphoid process. The measuring tape was applied tautly but not tightly avoiding compression or pinching of the skin. The smallest circumference at the measurement area was taken as waist circumference, recorded to the nearest 0.5cm (ACSM, 2008).
iii. Hip circumference
Similarly, hip circumference was measured to the nearest 0.5 cm using a non elastic plastic tape at the largest circumference around the buttocks, above the gluteal fold (posterior extension) (ACSM, 2008) .
iv. Waist-to-Hip Ratio (WHR)
As it name indicate, WHR is a comparison between circumferences of the waist to the circumference of the hip and it represents the distribution of body weight and perhaps body fat of an individual; an important predictor of health risks of obesity. The WHR or also known as the abdominal to gluteal ratio (A:G ratio) were expressed as a ratio hence there are no units. Calculation as below was used to calculate WHR (ACSM, 2008);
v. Resting blood pressure
Electronic blood pressure monitoring device; Medisana?? Upper Arm Blood Pressure Monitor MTD (Medisana AG.) were used to measure resting blood pressure. Subjects are requested to be free of stimulants which include nicotine products, caffeine products, alcohol or other cardiovascular stimulants for at least 30 minutes before the resting measurement. The subjects also did not involve in any strenuous exercise for at least 60 minutes before resting blood pressure measurement. For measurement of blood pressure, the subjects were asked to sit comfortably on a chair with back well supported, feet flat, leg uncrossed and relaxed. The right arm which was used for blood pressure measurement in this study was free from any clothing, rested on a table and slightly flexed at the elbow. An appropriate size cuff (a normal adult cuff for those with arm sizes between 24 and 32 cm, and a large adult cuff for those with arm sizes between 32 and 42 cm) was used. The BP cuff with bladder width between 40 to 50% of arm circumference and the length of bladder encircled at least 80% of the subject??s arm circumference was applied tightly at the level of subject??s heart. Second resting blood pressure measurement was done at least one full minute after the first measurement and if the first and second measurement differ by more than 5 mmHg, third measurement was taken after one full minute (ACSM, 2008).
vi. Resting heart rate
Resting heart rate measurement was taken together with resting blood pressure using similar device used for blood pressure measurement as above.
c. Assessment of body composition
Body composition was determined using the bioelectrical impedance method; Omron Karada Scan HBF-362?? Body Composition Monitor which gives information on;
ii. Body mass index
iii. Total body fat
iv. Subcutaneous fat percentage
v. Visceral fat level
vi. Skeletal muscle percentage
vii. Fat free mass were calculated by extracting total body fat from the body weight. Calculations as below were used.
Bioelectric impedance analysis is based on the principle that the resistance to an applied electric current is inversely related to the amount of fat-free mass within the body. This method does not take into account the location of body fat. This method of body composition analysis is very simple and quick to perform. The impedance measure is affected by body hydration status, body temperature, time of day, and therefore requires well controlled conditions to get accurate and reliable measurements. If a person is dehydrated, the amount of fat will likely be overestimated. Bioelectrical impedance measures the resistance of body tissues to the flow of a small, harmless electrical signal. The proportion of body fat can be calculated as the current flows more easily through the parts of the body that are composed mostly of water (such as blood, urine & muscle) than it does through bone, fat or air. It is possible to predict how much body fat a person has by combining the bioelectric impendence measure with other factors such as height, weight, gender, fitness level and age.
To ensure validity of the BIA measurement, several measures was taken to ensure that the subjects has normal hydration level.
* No eating or drinking within 4 hours of the test.
* No exercise within 12 hours of the test
* Urinate completely within 30 minutes prior to test
Omron Karada Scan HBF-362?? Body Composition Monitor was used for this test. Researcher inputs the subject??s age, gender and height and then the subject which wear light clothing steps onto the platform barefoot and holding the hand electrodes at 90 degrees. Electrodes in the foot and hand sensor pads send a low, safe signal through the body. Weight, body mass index, total body fat percentage, subcutaneous fat percentage, visceral fat level, and skeletal muscle percentage is calculated automatically in less than a minute.
d. Health related physical fitness
The remaining components of health related physical fitness level besides body composition were then assessed in all participants. Before starting these assessment, subjects were explained regarding the tests procedures and demonstration were done by researchers to ensure subjects clearly understand and able to perform the tests with correct techniques.
i. Cardiorespiratory fitness
Assessment of cardiorespiratory fitness to predict aerobic capacity of participants were done using Kasch Step test or also known as YMCA 3-Minutes Step test which relies on having the subject step up and down on a 30.48 cm (12 inch) step box. Before commencing test to the participants, the techniques were explained to the participants and demonstration of the alternating stepping cadence was done. A metronome was set at cadence of 96 beat per minute which gives a stepping rate of 24 steps per minute (4 clicks = one step cycle). With the first beat, one foot is stepped up on the bench, stepped up with the second foot on the second beat, stepped down with one foot on the 3rd beat, and stepped down with the other foot on the fourth beat. The subjects were also allowed to practice the stepping to the metronome cadence. After the three minutes are up, the subjects stop and palpate the pulse at the radial site while standing within the first 5 seconds. A 60 seconds pulse count is taken as the test score (toptrendsports.com, 2012, ACSM, 2008).
ii. Muscular endurance
To assess muscle endurance of the subjects, two test was administered; the push-up test and the curl-up test.
Push-up test: The test was administered with the male subjects starting in the standard ??down?? position (hand pointing forward and under the shoulder, back straight, head up, using the toes as the pivotal point) and the female subjects in the modified ??knee push-up?? position (legs together, lower leg in contact with mat with ankles plantar flexed, back straight, hands shoulder width apart, head up, using knees as the pivotal point). The subjects then raise the body by straightening the elbows (up position) and then return to the ??down?? position until the chin touches the mat. The stomach is maintained elevated and not touching the mat. The subjects position is ensure to be straight at all times and the subjects must push up to a straight arm position. the test was stopped when the subjects strains forcibly or is unable to maintain the appropriate technique within two repetition. The maximal number of push-ups performed consecutively without rest was counted as the score (ACSM, 2008).
Figure X: Push-ups performed by male subjects.
Figure X: Push-ups performed by female subjects.
One minute sit-up test (Crunch test): With the shoes remained on, the test was performed with the subjects assume a supine position on a mat, the knees at 90 degrees and the hands held across the chest. The trunk was then elevated to 30 degrees, lifting the shoulder blades off the mat; hands placed on the thighs and then subjects then do a slow, controlled curl-up until the hands reach the knee caps. The subjects were required to do as many curl-ups as possible in one minute and the number of curl-ups performed without pausing were recorded as the score (ACSM, 2008).
iii. Muscular strength
Handgrip test using a Lafayette?? 100kg Handgrip Dynamometer model LA-78010 was conducted to determine muscular strength of the subjects. The test was performed with the subject standing and using the dominant hand only. The grip bar of the dynamometer was adjusted for each subject, ensuring that the grip bar fit comfortably within the subject??s hand and the second joint of the finger fit under the handle of the handgrip dynamometer. Before starting test, the handgrip dynamometer is set to zero. The subject holds the handgrip dynamometer parallel to the side of the body at about waist level with the forearm levelled with the thigh and the arm is slightly flexed.
The subject then squeezes the handgrip dynamometer as hard as possible without holding their breath (Valsalva maneuver) and the results was recorded in kilograms. For each subject, the test was repeated two more times and the highest reading was taken as the measure of handgrip strength (ACSM, 2008).
Figure X: Use of hand-grip dynamometer to test
For assessment of flexibility, the Sit and Reach test (Trunk Flexion) using a sit-and-reach box was administered. Before starting the test, subjects were offered the opportunity to do some stretching exercises and light to moderate aerobic exercise for 5- 10 minutes to warm up their muscles. Subjects were allowed to take a few practice tries before the actual measurement and if the subject has any back problem or the test bothers them, the subject was excluded for the assessment. To assist with the best attempt, the subjects were advised to exhale and drop the head between the arms when reaching. The knees of the participants were kept extended (but not pressed down). Subjects were also advised to breathe normally and that they should not hold their breath during the test.
The subject sits without shoes and the sole soles of the feet flat against the sit-and-reach box at the 26cm mark. Inner edges of the soles were placed within 2cm of the measuring scale. With hands kept parallel, the participant then slowly reaches forward with both hands as far as possible and the fingertips were in contact with the measuring portion of the sit-and-reach box. This position was hold for approximately 2 seconds. The test were repeated three times and the score taken was the most distant point (in nearest cm) reached with the fingertips (ACSM, 2008).
Figure X: Sit and reach test using a sit-and-reach box.
e. Biochemical analysis
Five millilitres of blood from antecubital vein was taken from each subject after at least 12 hours overnight fasting for biochemical analysis of metabolic abnormalities. The blood was collected in two tubes, the first tube was plain tube without anticoagulant and the second tube was with oxalate/fluoride. The samples were send to a private independent laboratory (BP laboratory) for biochemical analysis below;
a. Fasting blood sugar
b. Fasting lipid profiles
14. Data collection
* At baseline, all participants were given advice on healthy lifestyle: promotion of healthy diet and physical activity.
* The study participants then completed questionnaires and assessments for;
b. Measurement of anthropometry.
c. Body composition measurement.
d. Health related components of physical fitness assessment.
e. Biochemical analysis for blood sugar and lipid profiles.
* The study participants were then randomized into two equal size groups. The first group undergo light resistance training using dumbbells and the second group undergo light resistance training using ankle-wrist weights for at least 15 minutes, three times per week. Group training was conducted for the first 3rd months in the dumbbell group with weekly adherence monitoring for both groups.
* At the end of first sixth and 12th week, patient were assessed for;
a. Anthropometry measurement
b. Body composition measurement
c. Physical fitness assessment
d. Biochemical analysis
* After the third months, participants in both groups were required to do the light resistance training on their own and at the end of 6th month, all the above parameters were assessed again to look at the sustainability of the training program and its effects.
Data entry and statistical analysis were done using SPSS software version 18.0 (SPSS Inc.).
As the same subjects were observed on multiple occasions (at baseline, 6th, 12th and 24th week), repeated measures analysis of variances were selected as the statistical test. As data were obtained repeatedly from the same subjects, RM ANOVA enables us to obtain information regarding individual??s patterns of change, were more economical as fewer subjects were required and enable us to reduce error of variance. Carry-over effects and latency effect were not involved in this study as there??s no cross-over of intervention in the study design. However, learning effect might be involved in this study especially in assessing health-related components of physical fitness as the subjects might improve with repetition of the assessment.
For all objectives, all the three different designs used in repeated measures were assessed in this study;
* Within group factors with regard to time (time effect)
o 6th week compared to baseline
o 12th week compared to baseline
o 24th week compared to baseline
o 12th week compared to 6th week
o 24th wee compared to 6th week
o 24th week compared to 12th week
* Between group factors regardless of time (treatment effect)
o Ankle-wrist weight group compared to dumbbell group
* Within-between group factors with regard to time (Time-treatment interaction).
o Ankle-wrist weight group compared to dumbbell group at baseline
o Ankle-wrist weight group compared to dumbbell group at 6th week
o Ankle-wrist weight group compared to dumbbell group at 12th week
o Ankle-wrist weight group compared to dumbbell group at 24th week
All the four steps involved in RM ANOVA were executed as below;
i. Data exploration and cleaning
ii. Fit the RM ANOVA model
iii. Checking assumption of;
a. Normality of residuals
b. Homogeneity of variance
c. Assumption of compound symmetry
iv. Interpretation, presentation and conclusion
Step 1: Data exploration and cleaning
Descriptive statistics for all the variables were obtained with data exploration. Any missing values and error in data entry were assessed before analysis with data cleaning. Subjects with missing data were excluded from analysis.
For numerical variables, descriptive statistics using syntax below were used to central point of numerical data, dispersion and graphical visualization of data normality (histogram with normality plot).
/STATISTICS=MEAN STDDEV MEDIAN
For categorical variables, syntax below was used to obtain frequency and percentage of those variables.
Step 2: Fit the repeated measure ANOVA model
Repeated measures ANOVA were executed using syntax below;
/WSFACTOR=time 4 Polynomial