Obesity
Conditions
Keywords
Aging, Obesity, Single muscle fiber contractile properties, Intramyocellular lipids, Resistance exercise
Brief summary
Obesity leads to a vicious circle that increases intramuscular fat, insulin resistance, promotes muscular dysfunction resulting in increased muscle fat accumulation. The study of muscle function and intramyocellular lipids is insufficient for obesity. Particularly, the study of mechanisms in muscle function and intramyocellular lipids is few nationally and internationally.
Detailed description
This study is prospective study. The goal of this study is 1. To examine the distribution and contractile properties (cross-sectional area, maximal force, specific force, maximal shortening velocity) of single muscle fiber sex/Myosin heavy chain (MHC) type-related differences, by extracting a single muscle fiber from the vastus lateralis in young men and women. 2. To examine the effects of intramyocellular lipids on physical activity ability, muscle dysfunction, and metabolic disorders in relation to aging and obesity. 3. To examine the effects of intramyocellular lipids on physical activity ability, muscular dysfunction, and metabolic disorders after 12 weeks resistance exercise intervention.
Interventions
OTHERResistance exercise with a gym stick
Exercise intervention: The resistance exercise intervention is performed with a gym stick for 3 times a week for 12 weeks. Exercise load is gradually increased by the number of times the band is wound and the speed of motion by dividing into three stages in 1-4 weeks (1st stage), 5-8 weeks (2nd stage) and 9-12 weeks (3rd stage).
Sponsors
Seoul National University Bundang Hospital
National Research Foundation of Korea
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
TRIPLE (Subject, Caregiver, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
20 Years to 80 Years
Healthy volunteers
Yes
Inclusion criteria
* Young men: Age (20-35 yrs), BMI (19-23 Kg/m2) * Young women: Age (20-35 yrs), BMI (19-23 Kg/m2) * Elderly women: Age (65-80 yrs), BMI (19-23 Kg/m2) * Elderly obese women: Age (65-80 yrs), BMI ( \>25 Kg/m2) * Subjects who can agree voluntarily.
Exclusion criteria
* Acute coronary syndrome. * Uncontrolled hypertension. * Subjects who took drugs which can affects neuromuscular system. * Severely impaired cognition * Subjects who cannot agree voluntarily
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Single muscle fiber MHC type distribution | Before intervention / after 12weeks intervention | Change from baseline fiber type distribution to 12 weeks after initial assessment. The MHC composition of single fibers was determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). MHC type distribution is analyzed to compare the change after intervention from baseline. |
| Single muscle fiber specific force (SF) | Before intervention / after 12weeks intervention | Change from baseline SF to 12 weeks after initial assessment. Chemically skinned vastus lateralis muscle fiber SF (kN/m2) is Po (kN) normalized by cross-sectional area (m2). SF is analyzed to compare the change after intervention from baseline. |
| Single muscle fiber maximal shortening velocity (Vo) | Before intervention / after 12weeks intervention | Change from baseline Vo to 12 weeks after initial assessment. Chemically skinned vastus lateralis muscle fiber Vo (FL/s) is measured by slack test procedure. The time required to take up the imposed slack was measured from the onset of the length step to the beginning of the tension redevelopment . For each amplitude of length, the fiber was reextended while relaxed to minimize nonuniformity of sarcomere length. A straight line was presented to a plot of length vs. time, using least-squares regression, and the slope of the line divided by the segment length was recorded as Vo for that fiber. Vo is analyzed to compare the change after intervention from baseline. |
| Total droplet area | Before intervention / after 12weeks intervention | Change from baseline total droplet area to 12 weeks after initial assessment. Total droplet area is determined by Oil-red-O staining. After staining, the total area (µm2) is analyzed to compare the change after intervention from baseline. |
| Number of lipid droplets | Before intervention / after 12weeks intervention | Change from baseline number of lipid droplets to 12 weeks after initial assessment. Number of lipid droplets determined by Oil-red-O staining. After staining, number of lipid droplets is analyzed to compare the change after intervention from baseline. |
| Single muscle fiber cross-sectional area (CSA) | Before intervention / after 12weeks intervention | Change from baseline CSA to 12 weeks after initial assessment. Chemically skinned vastus lateralis muscle fiber CSA (µm2) is measured by 3 dimensional microscopy. after analysis, CSA is compared the change after intervention from baseline. |
| Single muscle fiber maximal force (Po) | Before intervention / after 12weeks intervention | Change from baseline Po to 12 weeks after initial assessment. Chemically skinned vastus lateralis muscle fiber Po (mN) is measured by slack test procedure. after measurement, Po is analyzed to compare the change after intervention from baseline. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Isokinetic knee extension strength | Before intervention / after 12weeks intervention | Change from baseline Knee extension strength to 12 weeks after initial assessment. Isokinetic knee extension strength is measured in as peak torque achieved on an isokinetic dynamometer (BTE Primus, BTE tech, MD, USA) at 60° per second. |
| Hand grip strength | Before intervention / after 12weeks intervention | Change from baseline hand grip strength to 12 weeks after initial assessment. Participants are tested while they were seated, their arms are against their sides, their elbows are flexed 90 degrees. Hand grip Strength is measured in kilograms (kg) using a hand-grip dynamometer. The maximum value from either hand is used for analysis. |
Countries
South Korea
Outcome results
None listed