Blood Flow Restriction Training Combined With Abdominal draw-in Maneuver on Transverse Abdominis Strengthening

Study Overview
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Brief Summary
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This study expects to provide a new alternative way to improve the muscle activation, strength and activation of transverse abdominis in abdominal draw-in maneuver combined with blood flow restriction.

Detailed Description
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The transverse abdominis (TrA) is the deepest muscle layer of lateral and anterior abdominal wall and also known as a significant component of core stability. Abdominal draw-in maneuver (ADIM) is the main for the strengthening of the deep muscle, however, sufficient activation of TrA by ADIM is limited. Blood flow restriction (BFR) training is a technique combined with low intensity exercise that produces similar results to high intensity training. However, there is few evidences for BFR training on core muscles. Healthy adults (age ranged 18-34 years and BMI between 18.5 24.99) were randomly recruited in the study. For the intervention group, an inflatable cuff (14 cm in width * 84 cm in length) is warped around abdominal muscles below ribs which may cause to at least 60% restriction of blood flow detected by Power Doppler ultrasonography. All participants are instructed to perform ADIM both condition of BFR and BFR-free twice a week, for six weeks. Outcome measurements include Double leg lowering test (DLLT) for muscle strength, brightness mode ultrasound (USD) for muscle hypertrophy and electromyography (EMG) muscle activation. The same physical therapist will do the measurement at first week, third week and the sixth week.

Official Title
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Effects of Blood Flow Restriction Training Combined With Abdominal draw-in Maneuver on Transverse Abdominis Strengthening

Conditions
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Blood Flow Restriction, draw-in Maneuver, Transverse Abdominis

Intervention / Treatment
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* Behavioral: blood flow restriction
* Behavioral: sham blood flow restriction


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy subjects 20 35 years old BMI 18.5 24.99 Exclusion Criteria: Hypertension Have cardio-vascular disease Used to have abdominal operation or wound Have spinal surgeries or deformities Known neuromuscular or joint disease Pregnant

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: blood flow restriction<br>An inflatable cuff (14 cm in width * 84 cm in length) is warped around abdominal muscles below ribs which may cause to at least 60% restriction of blood flow detected by Power Doppler ultrasonography. All participants are instructed to perform abdominal draw-in maneuver both condition of BFR and BFR-free twice a week, for six weeks. | Behavioral: blood flow restriction<br>* an inflatable cuff (14 cm in width * 84 cm in length) is warped around abdominal muscles below ribs which may cause to at least 60% restriction of blood flow detected by Power Doppler ultrasonography. All participants are instructed to perform abdominal draw-in maneuver.<br>|
| Sham Comparator: sham blood flow restriction<br>an inflatable cuff (14 cm in width * 84 cm in length) is warped around abdominal muscles below ribs without inflation. All participants are instructed to perform abdominal draw-in maneuver. | Behavioral: sham blood flow restriction<br>* an inflatable cuff (14 cm in width * 84 cm in length) is warped around abdominal muscles below ribs without inflation. All participants are instructed to perform abdominal draw-in maneuver.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Muscle Thickness Change of Transverse Abdominis | muscle thickness change on week3, 4 and 5 compared with baseline | 3,4,5 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Internal Oblique Thickness Change | Data represents the muscle thickness change on week 3, 4 and 5 compared with baseline. The thickness of the muscle was calculated by the differences between the muscle thickness during contraction and the muscle thickness during resting position. If the muscle thickness during contraction was smaller than the muscle thickness during the resting position, therefore, the values would be negative. The values in baseline presented as negative may be because the internal oblique muscle thickness during contraction was smaller before receiving any training. Previous studies stated that after receiving ADIM and BFR training, the internal oblique muscle thickness will be thicker. Therefore, it was reasonable that the results in baseline presented negative values while the values became positive after receiving training. | baseline,3,4,5 weeks | 
| External Oblique Thickness Change | Data represents the muscle thickness change on week 3, 4 and 5 compared with baseline. The thickness of the muscle was calculated by the differences between the muscle thickness during contraction and the muscle thickness during resting position. If the muscle thickness during contraction was smaller than the muscle thickness during the resting position, therefore, the values would be negative. The values in baseline presented as negative may be because the external oblique muscle thickness during contraction was smaller before receiving any training. After receiving ADIM and BFR training, the tranverse abdominis and internal oblique muscle thickness will be thicker while the external oblique will be thinner due to the compression from the TrA and IO muscles. | baseline,3,4,5weeks |