The effect of whole body vibration training on insulin sensitivity in overweight adolescents: A randomised controlled trial
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Open Access
Type
ThesisThesis type
Doctor of PhilosophyAuthor/s
Ramjan, Kim AnnAbstract
Clinical insulin resistance (IR), commonly seen in the obese adolescent, precedes a diagnosis of Type 2 diabetes. Paediatric weight management programs improve insulin sensitivity (Si) and metabolic profile. This RCT investigated whether whole body vibration training (WBVT) could ...
See moreClinical insulin resistance (IR), commonly seen in the obese adolescent, precedes a diagnosis of Type 2 diabetes. Paediatric weight management programs improve insulin sensitivity (Si) and metabolic profile. This RCT investigated whether whole body vibration training (WBVT) could enhance Si in obese adolescents, in addition to lifestyle intervention. Secondary outcome measures included change in anthropometry, musculoskeletal and cardiorespiratory fitness (CRF). Participants had central adiposity. Adverse anthropometry was associated with poorer Si, increased weight and BMI. IR correlated with greater inflammation. Acanthosis nigricans, in dark skinned individuals, detected biochemical hyperinsulinaemia. Two thirds were female; males had the highest BMI. The average fasting insulin was 33.8mU/L. The group was highly insulin resistant at baseline with HOMA-IR 7.62 and WBISI 1.74. Metabolic syndrome was prevalent ranging from 23-44%. Males had higher systolic blood pressure z score at baseline. The group had mild elevation in aspart aminotransferase. Triglycerides positively correlated with alanine aminotransaminase, mainly in males. Participants were inactive with increased sedentary times. CRF, muscle force and power generation were reduced. Obese individuals had higher areal bone mineral density (BMD) and content (BMC) for age but normal values for height. Females had a higher BMD and BMC to males. Lean tissue mass was a predictor of BMD. Increased waist circumference negatively affected BMC and BMD. Lifestyle intervention improved BMI z score (-0.8 vs. -0.08, p<0.039) in the lifestyle and WBVT group respectively and was associated with improvements in fasting glucose (-0.3 vs. -0.0, p<0.047). Si showed non-significant improvement. WBVT, increased lean tissue mass by almost 0.5kg. There was no association between bone and mineral turnover and energy homeostasis. Low vitamin D and dark skin were associated with higher fasting insulin, lower WBISI and higher HOMA-IR. Retention to the study was high with dropout of 2.3%, but compliance to the WBVT exercise intervention was poor. This study confirmed lifestyle measures in the management of obesity and insulin resistance and provides evidence of the safety of WBVT as an efficient method of improving lean tissue mass in obese adolescents.
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See moreClinical insulin resistance (IR), commonly seen in the obese adolescent, precedes a diagnosis of Type 2 diabetes. Paediatric weight management programs improve insulin sensitivity (Si) and metabolic profile. This RCT investigated whether whole body vibration training (WBVT) could enhance Si in obese adolescents, in addition to lifestyle intervention. Secondary outcome measures included change in anthropometry, musculoskeletal and cardiorespiratory fitness (CRF). Participants had central adiposity. Adverse anthropometry was associated with poorer Si, increased weight and BMI. IR correlated with greater inflammation. Acanthosis nigricans, in dark skinned individuals, detected biochemical hyperinsulinaemia. Two thirds were female; males had the highest BMI. The average fasting insulin was 33.8mU/L. The group was highly insulin resistant at baseline with HOMA-IR 7.62 and WBISI 1.74. Metabolic syndrome was prevalent ranging from 23-44%. Males had higher systolic blood pressure z score at baseline. The group had mild elevation in aspart aminotransferase. Triglycerides positively correlated with alanine aminotransaminase, mainly in males. Participants were inactive with increased sedentary times. CRF, muscle force and power generation were reduced. Obese individuals had higher areal bone mineral density (BMD) and content (BMC) for age but normal values for height. Females had a higher BMD and BMC to males. Lean tissue mass was a predictor of BMD. Increased waist circumference negatively affected BMC and BMD. Lifestyle intervention improved BMI z score (-0.8 vs. -0.08, p<0.039) in the lifestyle and WBVT group respectively and was associated with improvements in fasting glucose (-0.3 vs. -0.0, p<0.047). Si showed non-significant improvement. WBVT, increased lean tissue mass by almost 0.5kg. There was no association between bone and mineral turnover and energy homeostasis. Low vitamin D and dark skin were associated with higher fasting insulin, lower WBISI and higher HOMA-IR. Retention to the study was high with dropout of 2.3%, but compliance to the WBVT exercise intervention was poor. This study confirmed lifestyle measures in the management of obesity and insulin resistance and provides evidence of the safety of WBVT as an efficient method of improving lean tissue mass in obese adolescents.
See less
Date
2016-07-08Licence
The author retains copyright of this thesis. It may only be used for the purposes of research and study. It must not be used for any other purposes and may not be transmitted or shared with others without prior permission.Faculty/School
Sydney Medical SchoolDepartment, Discipline or Centre
Discipline of Child and Adolescent HealthAwarding institution
The University of SydneyShare