South Pacific Islands Resist diabetes with Intense Training: A randomised trial

• Register: ANZCTR
• Last refreshed on: 22 February 2013
• Main ID: ACTRN12609001085268
• Date of registration: 18/12/2009
• Primary sponsor: University Massey University
• Public title: South Pacific Islands Resist diabetes with Intense Training: A randomised trial SPIRIT Study
• Scientific title: The SPIRIT Study: South Pacific Islands Resist diabetes with Intense Training: A randomised trial
• Date of first enrolment: 1/02/2008
• Target sample size: 40
• Recruitment status: Completed
• URL: http://www.anzctr.org.au/ACTRN12609001085268.aspx
• Study type: Interventional
• Study design: Randomised controlled trial Parallel

Countries of recruitment

New Zealand

Contacts

• Name: William R. Sukala,MSc

• Name: William R. Sukala,MSc

Key inclusion & exclusion criteria

Inclusion criteria: Self-identified Polynesian descent (Maori, Pacific Islands people).
Diagnosed type 2 diabetes.
Central obesity as defined by a waist girth of 88cm in women and 102cm in men.
No change in diabetes medications for previous two months.
No documented cardiac history or stable cardiac history for previous 6 months.
Not currently taking exogenous insulin injections.
Must be stable and medically managed.
Signed consent from their general practitioner (GP) or specialist.
Exclusion criteria: Diabetic complications which may be worsened by weight lifting exercise.
Change in meds during previous 2 months.
Unstable cardiovascular disease, stroke, or other conditions which might be worsened by weight lifting exercise.

Age minimum: 18 Years
Age maximum: 60 Years
Gender: Both males and females

Health Condition(s) or Problem(s) studied

obesity

type 2 diabetes

Intervention(s)

16 weeks of progressive resistance training (weight lifting), three times per week, 45 min per session on eight machine-based resistance exercises in a circuit format: seated leg press, knee extension, knee flexion, chest press, lat pulldowns, overhead press, biceps curls, triceps extension (Cybex International, Medway, MA). Initial weights starting weights determined as a percentage of the extrapolated 1-repetition maximum (1RM) as previously described by Brzycki et al (1993). Thereafter using a graduated periodized regimen where subjects progress from 65% to 85% of their extrapolated 1RM over the course of phase 1, two sets at 85% during phase 2, three sets at 85% during phase 3, and a continuation of three sets at 85% until conclusion of the intervention. Perform 6 to 8 repetitions with a 1 minute rest between sets. Workloads increased by 5% when subjects can perform 10 repetitions. Onsite exercise leaders supervised by lead clinical exercise physiologist encourage exercise at a a perceived exertion of “hard,” or 15, on the Borg scale.

Primary Outcome(s)

glycaemic control (haemoglobin A1c): Determined by ion exchange high pressure liquid chromatography using the Bio-Rad D-10 analyzer (Bio-Rad Laboratories, Hercules, CA) with a coefficient of variation (CV) of 3%.

Secondary Outcome(s)

Activity Levels (International Physical Activity Questionnaire)

Adiponectin: Determined by radioimmunoassay (Linco Research, St. Charles, MO, USA) with a CV of 8.8%.

Anthropometric indices (Height, weight, Body Mass Index (BMI), waist and hip circumference, waist/hip ratio:

Height and weight measured to the nearest 0.1cm and 0.1kg on a standard hospital-grade stadiometer and scale, respectively. BMI calculated from standard formula: kg/m2. Waist circumference was measured to the nearest 0.1cm at the end of normal expiration and the midpoint between the lower costal margin and the iliac crest using, and hip circumference taken with feet together at the widest protuberance of the buttocks, using a retractable steel tape measure (model F10-02. KDS Corporation, Japan).

Blood lipids (Total Cholesterol, High Density Lipoprotein (HDL), Low Density Lipoprotein (LDL), Triglycerides (TG) were determined via standard enzymatic methods (Roche/Hitachi lipid assay kits) with a Roche Modular Analyzer with a CV of 3% on each assay. LDL mathematically determined as total cholesterol minus HDL minus (0.45 x TG).

Body composition: Lean body mass (LBM), fat mass (FM), and percent body fat (%BF) estimated via bioelectrical impedance analysis (BIA) on a Tanita TBF-310 analyzer (Tanita Corporation, Arlington Heights, Illinois, USA).

C-Reactive Protein: Determined by latex agglutination method on the Roche Modular Analyzer with a CV of 4%.

Dynamic upper and lower body strength: Due to level of obesity and deconditioning in this population and because strength was only determined as a means to identify starting weights, a 1-Repetition Max (1-RM) was deemed unnecessary. Instead a 10RM as determined by the protocol set forth by Brzycki (1993) was more appropriate to minimise delayed onset muscle soreness and possibly minimise early dropout.

haemodynamics (Heart rate (HR) and Blood Pressure (BP)): Seated blood pressure was measured in duplicate on the left arm after 5 minutes rest on a standard hospital-grade sphygmomanometer. Heart rate measured by counting radial pulse for a full 60 seconds. Exercise pulse determined manually on all subjects, but corroborated by use of pulse monitor on aerobic equipment.

Insulin resistance: Determined from fasting glucose and insulin using the most recent HOMA2-IR calculator (version 2.2.2, Oxford University).

muscle markers (muscle fibre type and cross-sectional area, mitochondrial density, intramuscular triglyceride, capillary density, GLUT4). Method: standard biopsy of vastus lateralis by highly trained/experienced doctor, snap frozen samples, later sectioned, mounted, and results determined by immunohistochemical methods and electron microscopy. Digital images captured analzyed on software to quantify indicated parameters.

Quality of Life Short-Form 36(SF-36) questionnaire.

The SF36 quality of life questionnaire is comprised of 36 questions which encompass 8 different areas of physical and mental health and is useful for comparing the burden of different diseases, differentiating the health benefits produced by different treatments, and in screening individual patients.

Secondary ID(s)

None

Source(s) of Monetary Support

Massey University