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Reducing LDL Cholesterol through MICT and HIIT

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Exercise can be used as a treatment in improving health status. More effective, if it was applied to the subject of obesity. Obese people had high levels of LDL cholesterol (low density lipoprotein), which can lead to the emergence of cardiovascular diseases such as hypertension, stroke and coronary heart disease. By exercising regularly, the chances of the risk of these diseases will be reduced. Exercise with moderate intensity continuous training (MICT) and high intensity interval training (HIIT) methods can effectively lower LDL cholesterol levels. The exercise process was done for 6 weeks with density 4 times per week. The subjects used were 21 experimental animals of wistar male rats, which then were divided into 3 groups equally (control, MICT and HIIT). The MICT exercise was at the 50-60% baseline intensity, while HIIT was at 100% maximum baseline intensity. Data collection of LDL levels used ABX Pentra LDL Direct CP analysis. Data analysis technique used Anova test and Tukey HSD advanced test with level of significance 0,05. The results were shown that MICT and HIIT effectively lowering LDL levels in obese subjects. It can be interpreted that exercise regularly give positive effects on the improvement of health conditions, especially at cholesterol levels of the body. Keywords: MICT, HIIT, low-density lipoprotein, obesity.
Reducing LDL Cholesterol through MICT and HIIT
Yanuar Dhuma Ardhiyantoa*, Samsul Mu’arifa, Widiyantob, Hadionoc and Andryas Yuniartoc
Sport Science Post-graduate Program, Yogyakarta State University
Exercise can be used as a treatment in improving health status. More effective, if it was
applied to the subject of obesity. Obese people had high levels of LDL cholesterol (low
density lipoprotein), which can lead to the emergence of cardiovascular diseases such
as hypertension, stroke and coronary heart disease. By exercising regularly, the chances
of the risk of these diseases will be reduced.
Exercise with moderate intensity continuous training (MICT) and high intensity
interval training (HIIT) methods can effectively lower LDL cholesterol levels. The
exercise process was done for 6 weeks with density 4 times per week. The subjects used
were 21 experimental animals of wistar male rats, which then were divided into 3
groups equally (control, MICT and HIIT). The MICT exercise was at the 50-60%
baseline intensity, while HIIT was at 100% maximum baseline intensity. Data
collection of LDL levels used ABX Pentra LDL Direct CP analysis. Data analysis
technique used Anova test and Tukey HSD advanced test with level of significance
The results were shown that MICT and HIIT effectively lowering LDL levels in obese
subjects. It can be interpreted that exercise regularly give positive effects on the
improvement of health conditions, especially at cholesterol levels of the body.
Keywords: MICT, HIIT, low-density lipoprotein, obesity.
The prevalence of obesity was increasing worldwide, both in children and adults.
Associated obesity increases the risk of cardiovascular diseases, such as hypertension,
type 2 diabetes, and all diseases directly related to blood vessels (Fisher et al, 2015: 2).
This was a condition that should be avoided or reduced by obese people.
In the Lancet journal, the number of obese people in the world rose from 875 million
people in 1980 to 2,1 billion people in 2013. This increased number was not separated
from the pattern of everyday life and lack of sports activities. In this condition, calorie
intake was greater than calories expenditure, so the leftovers of the food that was not
into energy will be stored as fat. Overweight body has a higher fat content, especially
LDL-C/low density lipoprotein cholesterol.
Lowering and maintaining body fat is important for health. Therefore, every individual
needs to pay attention to their respective conditions in order to avoid various
degenerative diseases. These negative impacts can be reduced through physical activity.
Of course, with regular and measurable activity.
Physical exercise is known to have a positive effect on health of the body especially in
order to improve metabolism status of fat. According to Alahmadi (2014: 3), exercise
to reduce body fat levels can be done with moderate-intensity continuous training
(MICT) method that can increase mitochondrial biogenensis activity through activation
of metabolic enzymes such as AMPK, CPT-1 and ACC. High intensity interval training
(HIIT) can reduce body fat levels because it can activate the cardio metabolic
component, so that the adaptation of these conditions can increase the mobilization of
fatty acids on mitochondria and affect the improvement of lipid profile.
The influence of MICT and HIIT is quite effective in lowering body fat levels, through
their respective mechanisms. The mentioned reviews can be drawn to some core issues
such as: moderate intensity continuous training (MICT), high intensity interval training
(HIIT), overweight subjects and LDL levels. Determining the appropriate dose of
exercise is a positive action.
Design and Sampling
Implementation of data retrieval used experimental laboratories method and random
control group post-test only design. The basic use of this method was to provide practice
of overweight subjects to know the adaptation of 2 types of exercise on changes of LDL
The method that used to determine number of subjects refers to "Guidelines for the care
and use of mammals in neuroscience and behavioral research" issued by the Institute
for Laboratory Animal Research of the United State of America. This step was
determined by researchers to obtain a representative sample size.
The subjects used experimental animals (rattus norvegicus strain wistar). The use of
experimental animals in this study aims to facilitate researchers in controling the overall
aspect that was applied in the research to support the accuracy of research results.
The sampling technique was carried out randomly based on the following inclusion
1. Rat type (rattus norvegicus strains wistar).
2. Male sex.
3. Age 2-3 months and untrained (untrained).
4. Healthy and not disabled.
5. Overweight status.
The feed used during the research process was Rations 511, 521 and Japfa Comfeed
Pellete. The dosage used based on (Sengupta, 2013: 627), given as much as 10 grams /
100 grams of body weight, so each day about 20-30 grams. The amount of drink was
10-12 ml / 100 gram body weight (20-30 ml). Checking the amount of drink was seen
on the size written on ad libitum.
Experimental Protocol
An exercise program on MICT and HIIT methods was performed by a special treadmill
for mice in 24 times of treatment. MICT was at 50-60% maximum speed capability,
while HIIT at 100% maximum speed capability. In knowing the maximum speed
capability used the increase pattern 1 m/min every minute.
Blood Analysis
LDL content analysis used test method of ABX Pentra LDL Direct CP in Clinical
Pathology Laboratory of Universitas Brawijaya Malang, Indonesia. The analysis was
performed 72 hours after the last exercise.
Statistical Analysis
Anova and Tukey Test, All data were tested with 95% significance level (standard
error 0,05%) and used SPSS Statistics 23 application program.
Figure 1. LDL Condition
Anova test results show sig value. 0,017 < 0,05, so this means that moderate-intensity
continuous training (MICT) and high-intensity interval training (HIIT) effect on low-
density lipoprotein (LDL) levels".
Tukey test looks sig value. 0,013 < 0,05 in the control group and MICT, so that the
control group and MICT were different. For control group and HIIT sig value. 0,309 >
0,05 and MICT and HIIT groups of sig values. 0,236 > 0,05. These values > 0,05, this
indicates that there is no significant difference between the control group-HIIT and
In the LDL Tukey test table, the MICT and control groups have sig values. 0,013 <
0,05, while the HIIT and control group had a value of 0,309 > 0,05. So, the effectiveness
of moderate-intensity continuous training (MICT) influences Low-density lipoprotein
Weight and LDL Condition
The control group had an average body weight 291 gram. The group progressively
gained weight from beginning to the end. This description corresponds to a sedentary,
which the body condition was not routinely doing physical activity or can be called a
passive category. Increased weight will coincide with the higher levels of cholesterol
in the blood (Nhanes, 2003: 1). This condition also corresponds to high levels of LDL
control group that is 18.71 mg/dL or about 30% higher than the MICT and HIIT groups.
Thus, the increase in LDL levels is positively correlated with weight gain (passive
In the treatment group, the MICT group had a final average 258 gram and 249 gram on
HIIT group. This treatment group experienced the same weight loss phase. The weight
loss stage occurs at the sixth week. The MICT and HIIT groups did not have a
significant difference, but the treatment group compared with the control group had
significant differences. So, clearly illustrated the difference between active subjects and
passive subjects. This result has a same point with Jung's research, et al. (2015: 6), that
the weight of the MICT and HIIT groups did not different.
At another source, Haram et al (2008: 729), who used an exercise program for 8 weeks
and concluded that effective weight loss was performed with moderate intensity and
high intensity exercise. The study also illustrated that there was no difference in weight
loss between MICT and HIIT groups. It can be interpreted that both types of exercise
have the same effectiveness in losing weight on the subject of obesity / overweight.
Weight loss in the MICT group occurs through the process of increased use of fat in the
body to be used as energy during moderate intensity exercise. Increased use of these
fats occurs in the burning of free fatty acids (FFA) and triacylglycerol (TG). Fat
oxidation in moderate intensity exercise, effectively occurs during the exercise process
and then the need will be lowered after the training process is completed. This causes
the adipose tissue to be reduced through hormonal stimulation by the sympathetic
nervous system. These results are appropriate that exercise with the MICT method can
lose weight.
In HIIT group, the condition of weight loss occurs due to increased of fat oxidation
during exercise and takes less time. HIIT can increase fat oxidation and mitochondrial
density. Energy sources used are carbohydrates and fats. The higher intensity will be
increasingly used carbohydrates, because the amount of oxygen decreases to supply the
process of fat metabolism. Increased fat oxidation occurs because the metabolism in the
muscle increases, so that oxygen consumption rises after completion. HIIT also
stimulates post-exercise metabolism such as EPOC supplied by fat during the recovery
phase (Alahmadi, 2014: 4).
From these results, MICT and HIIT are equally effective in weight loss programs, so
this exercise method is well suited for obese / overweight subjects.
Figure 2. LDL on Each Subject
Exercise is assumed to reduce the amount of LDL in the blood. This was reflected in
the mean results of control group LDL levels of 18.71 mg/dL, MICT is 13.57 mg/dL
and HIIT is 16.29 mg/dL. It is seen that in the treatment group had a lower average
compared to the control group. Statistically significant results, it appears that exercise
has a positive effect in lowering LDL levels. These results support Brites (2006)
research that aerobic and anaerobic exercise is known to alter lipoprotein profiles and
increase HDL, associated with anti-oxidant enzymes.
The amount of LDL in the blood should always be controlled, because it is associated
with foam cell formation and other defects in blood vessel changes (Watanabe, 2004).
Through sports, it can be proven that its influence is good and positive. Therefore, it
can be concluded that exercise has an effect on either improving or lowering LDL levels
in overweight/obese subjects.
Moderate-intensity continuous training (MICT) and High-intensity interval training
(HIIT) have a positive effect on adaptation of low-density lipoprotein (LDL) levels.
The adaptation works well with LDL levels decreased after the exercise process.
1. Exercise with moderate intensity is suitable and safe to use on the subject of
overweight and effective in the process of cholesterol and weight reduction.
2. Maintain intake of foods with balanced nutrition to support the continuity of body
metabolism is better.
3. Maintain body fitness through exercise is good for healthy body and protected from
various diseases.
14 15 17 18 18
24 25
12 12 13 13 14 15 16
13 14 14
17 18 18 20
Low Density Lipoprotein
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My incredible appreciation goes to friends who have helped in completing the research
and this article. Thanks to LPDP who has facilitated the research and publication from
the initial process to the end. Thanks to Universitas Negeri Yogyakarta and Universitas
Brawijaya who have given permission and let us do research.
ResearchGate has not been able to resolve any citations for this publication.
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Physical activity is known to play a cardioprotective role. Nevertheless, a paradox seems to arise when considering that aerobic exercise enhances oxidative stress. In previous works, we showed that free radical formation during physical activity was counteracted by an increase in antioxidant defenses. Low density lipoprotein (LDL) oxidation is a crucial step in atherosclerosis, process that can be inhibited by high density lipoprotein (HDL) through its oxidable components or associated enzymes like paraoxonase (PON) and platelet-activating factor acetylhydrolase (PAF-AH). In this study, we evaluated copper-induced oxidation in isolated LDL and HDL fractions, and the effect of HDL on LDL oxidation in samples from well trained amateur athletes who were participating in an ultra-distance triathlon (n=18) in comparison with healthy sedentary controls (n=18). PON and PAF-AH activities and PON phenotype were also evaluated. The oxidability of isolated lipoproteins, as well as HDL antioxidant capacity, was similar in both groups of subjects. After classification by paraoxonase phenotype, only sportsmen belonging to the QR phenotype showed higher HDL susceptibility to in vitro oxidation (thiobarbituric reactive substances, TBARS) than controls (p<0.05). HDL oxidability exhibited a positive correlation with its triglyceride content (r=0.58; p<0.01). Similarly, HDL capacity to inhibit LDL oxidation was increased in athletes (p<0.05) which was positively associated with HDL oxidability (HDL-TBARS: r=0.55, p<0.005; HDL-lag time: r=0.45, p<0.01; HDL-D max: r=0.35, p<0.05). In conclusion, regular aerobic exercise was associated to a more efficient antioxidant function played by HDL from PON-QR carriers, which could constitute an adaptive response to the increased oxidative stress.