The Insulin Sensitivity Using Aerobic Interval Conditioning

NCT ID: NCT01286922

Last Updated: 2022-09-15

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 42 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2009-07-31
• Study Completion Date: 2012-02-29

Brief Summary

The Insulin Sensitivity using Aerobic Interval Conditioning (ISAIC) trial will compare traditional aerobic training (AER) to interval training (INT) in sedentary, overweight/obese men at risk for pre-diabetes. The investigators will randomly assign 42 individuals to 3 months of monitored exercise using a randomly assisgned design where participants will exercise under either AER or INT training conditions. The AER training condition will be consistent with "standard-of-care" recommendations. Exercise training will entail one 3-month blocks of either AER or INT. Training will consist of 1) a 1-month ramp up period, 2) 1-month of traditional aerobic training and 3) 1-month of either continued AER or INT.

Detailed Description

It is currently estimated that type II diabetes (T2D) affects 5-8% of adults. Also recognized is a transitional group of individuals whose control of blood glucose is abnormal, but not yet considered diabetic. These individuals are classified as having pre-diabetes, which is defined as having impaired fasting glucose (IFG;fasting glucose 100-125 mg/dl), impaired glucose tolerance (IGT; post 2-h glucose load; 140-199 mg/dl) or both. This population represents a significant segment of the population as it is estimated that approximately 23% of Americans have pre-diabetes (IGT or IFG). Two unifying features associated with these metabolic impairments is a strong link to obesity and physical inactivity. Regular exercise positively influences IFG/IGT and obesity, and represents an important therapy for preventing the progression to T2D by enhancing several mechanisms of action including improved: glucose metabolism, muscle respiratory capacity, mitochondrial respiratory chain activity and ß-oxidation. Importantly, the dose of physical activity required to promote metabolic benefits appears to be obtainable for most individuals with as little as ~1000 kcal/w of aerobic activity.

While most exercise policy statement guidelines recommend that exercise be performed within an intensity ranging of 40-85% V02max, newer guidelines, such as the recently updated Physical Activity and Public Health Recommendations recognize that few studies have examined the effects of intensity, duration, or frequency of physical activity independent of their contribution to the total amount of physical activity. Accordingly, this writing group specifically recommended that, "based on recent data, there is some indication that vigorous-intensity activities may have greater benefit for reducing cardiovascular disease and premature mortality than moderate-intensity physical activity .... that much more work is needed is this area."

Conditions

Pre-diabetes

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

Interval Training

The target intensity for the INT group is 2 min at about 95% of baseline VO2max followed by 2 min of recovery at 40-50% of VO2max. Regardless of the training method each participant will be "locked" into a weekly energy expenditure of 12 kilocalories per kilogram of body weight per week (KKW).

Group Type: EXPERIMENTAL

Behavioral: exercise

Intervention Type: OTHER

Specific Aim: We will identify, recruit, assess, and randomly assign 42 sedentary, overweight-obese individuals who are at risk for pre-diabetes to an AER or INT training group in order to test the hypothesis:

• Individuals randomized to INT will have greater improvements in insulin sensitivity than individuals assigned to traditional AER.

Secondary Aim: We will measure maximal cardiorespiratory fitness (VO2max/peak) in order to test the hypothesis:

• Individuals randomized to the INT group will have a greater improvement in VO2max/peak than individuals in traditional AER group.

Aerobic Conditioning

During the first AER training condition, we will train all participants at an energy expenditure of 12 kcal/kg/wk (KKW). The target exercise intensity for the AER group will be 50%-70% of baseline V02max.

Group Type: PLACEBO_COMPARATOR

Behavioral: exercise

Intervention Type: OTHER

Specific Aim: We will identify, recruit, assess, and randomly assign 42 sedentary, overweight-obese individuals who are at risk for pre-diabetes to an AER or INT training group in order to test the hypothesis:

• Individuals randomized to INT will have greater improvements in insulin sensitivity than individuals assigned to traditional AER.

Secondary Aim: We will measure maximal cardiorespiratory fitness (VO2max/peak) in order to test the hypothesis:

• Individuals randomized to the INT group will have a greater improvement in VO2max/peak than individuals in traditional AER group.

Interventions

Behavioral: exercise

Specific Aim: We will identify, recruit, assess, and randomly assign 42 sedentary, overweight-obese individuals who are at risk for pre-diabetes to an AER or INT training group in order to test the hypothesis:

• Individuals randomized to INT will have greater improvements in insulin sensitivity than individuals assigned to traditional AER.

Secondary Aim: We will measure maximal cardiorespiratory fitness (VO2max/peak) in order to test the hypothesis:

• Individuals randomized to the INT group will have a greater improvement in VO2max/peak than individuals in traditional AER group.

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• Age 30 to 60 years, inclusive
• BMI greater than or equal to 25 - less than or equal to 35 kg/m2
• Waist circumference >38"; Waist-to-Hip Ratio >0.95 Sedentary Lifestvle
• Not physically active greater than or equal to 3 days/week-l for 20 min each time for the previous 6 months,
• Not participating in regular resistance exercise

Exclusion Criteria

• Resting blood pressure greater than or equal to 160/100 mm Hg
• Triglycerides greater than or equal to 500 mg/dL
• Factors that may limit adherence to intervention or affect conduct of the trial such as lack of time, amount of travel, and/or work or family stressors
• Unable or willing to communicate with staff, to provide written informed consent, or accept the randomized assignment
• Failure to complete behavioral run-in and baseline testing
• Hospitalization for depression in the last 6 months
• Not physically capable of performing the exercise required of the study protocols
• Consuming >14 alcoholic beverages per week
• Plans to be away >4 weeks in the next 6 months
• Lack of support from primary health care provider or family members
• Signficant weight loss in the past year (>20 kg) or current use of weight loss medications
• Current diagnsis of schizophrenia, or other psychotic disorders, or bipolar disorder
• Another member of household is a participant or staff member of the study.
• History of bariatric surgery within last 3 years,
• Other temporary intervening event, such as sick spouse, bereavement, or recent move.
• Other medical, psychiatric, or behavioral limitations that in the view of the principal investigator may interfere with study participation or the ability to follow the intervention protocol.
• Underlying diseases or conditions likely to limit lifespan and/or affect the safety of the intervention
• Cancers requiring treatment in the past 5 years, unless prognosis is excellent.
• Self-report HIV or tuberculosis.
• History or evidence of serious arrhythmias, cardiomyopathy, congestive heart failure, aortic aneurysm, or heart transplantation.
• Renal disease: currently receiving dialysis.
• Type I diabetes mellitus
• Type 2 diabetes mellitus, defined as:

Fasting plasma glucose levels greater than or equal to 26 mg/dL 2-hour postprandial Oral Glucose Tolerance Test results greater than or equal to 200 mg/dL

• Any other medical condition or disease that is life threatening or that can interfere with or be aggravated by exercise.
• Chronic obstructive lung disease, peripheral vascular disease or angina that limits ability to follow exercise protocol.
• Advanced neuropathy or retinopathy.
• Smoker or have used nicotine/tobacco products within the last 12 months.

• Minimum Eligible Age: 30 Years
• Maximum Eligible Age: 60 Years
• Eligible Sex: MALE
• Accepts Healthy Volunteers: Yes

Sponsors

National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)

NIH

Sponsor Role: collaborator

Pennington Biomedical Research Center

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Conrad P. Earnest, PhD

Role: PRINCIPAL_INVESTIGATOR

Pennington Biomedical Research Center

Timothy S. Church, MD, MPH, PhD

Role: STUDY_DIRECTOR

Pennington Biomedical Research Center

Locations

Pennington Biomedical Research Center

Baton Rouge, Louisiana, United States

Countries

United States

References

Harris MI, Flegal KM, Cowie CC, Eberhardt MS, Goldstein DE, Little RR, Wiedmeyer HM, Byrd-Holt DD. Prevalence of diabetes, impaired fasting glucose, and impaired glucose tolerance in U.S. adults. The Third National Health and Nutrition Examination Survey, 1988-1994. Diabetes Care. 1998 Apr;21(4):518-24. doi: 10.2337/diacare.21.4.518.

Reference Type: BACKGROUND

PMID: 9571335 (View on PubMed)

Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. Report of the expert committee on the diagnosis and classification of diabetes mellitus. Diabetes Care. 2003 Jan;26 Suppl 1:S5-20. doi: 10.2337/diacare.26.2007.s5. No abstract available.

Reference Type: BACKGROUND

PMID: 12502614 (View on PubMed)

American Diabetes Association. Diagnosis and classification of diabetes mellitus. Diabetes Care. 2007 Jan;30 Suppl 1:S42-7. doi: 10.2337/dc07-S042. No abstract available.

Reference Type: BACKGROUND

PMID: 17192378 (View on PubMed)

Benjamin SM, Valdez R, Geiss LS, Rolka DB, Narayan KM. Estimated number of adults with prediabetes in the US in 2000: opportunities for prevention. Diabetes Care. 2003 Mar;26(3):645-9. doi: 10.2337/diacare.26.3.645.

Reference Type: BACKGROUND

PMID: 12610015 (View on PubMed)

Zierath JR, Tsao TS, Stenbit AE, Ryder JW, Galuska D, Charron MJ. Restoration of hypoxia-stimulated glucose uptake in GLUT4-deficient muscles by muscle-specific GLUT4 transgenic complementation. J Biol Chem. 1998 Aug 14;273(33):20910-5. doi: 10.1074/jbc.273.33.20910.

Reference Type: BACKGROUND

PMID: 9694838 (View on PubMed)

Lund S, Holman GD, Schmitz O, Pedersen O. Contraction stimulates translocation of glucose transporter GLUT4 in skeletal muscle through a mechanism distinct from that of insulin. Proc Natl Acad Sci U S A. 1995 Jun 20;92(13):5817-21. doi: 10.1073/pnas.92.13.5817.

Reference Type: BACKGROUND

PMID: 7597034 (View on PubMed)

Hayashi T, Wojtaszewski JF, Goodyear LJ. Exercise regulation of glucose transport in skeletal muscle. Am J Physiol. 1997 Dec;273(6):E1039-51. doi: 10.1152/ajpendo.1997.273.6.E1039.

Reference Type: BACKGROUND

PMID: 9435517 (View on PubMed)

Turcotte LP, Richter EA, Kiens B. Increased plasma FFA uptake and oxidation during prolonged exercise in trained vs. untrained humans. Am J Physiol. 1992 Jun;262(6 Pt 1):E791-9. doi: 10.1152/ajpendo.1992.262.6.E791.

Reference Type: BACKGROUND

PMID: 1319676 (View on PubMed)

Kiens B, Essen-Gustavsson B, Christensen NJ, Saltin B. Skeletal muscle substrate utilization during submaximal exercise in man: effect of endurance training. J Physiol. 1993 Sep;469:459-78. doi: 10.1113/jphysiol.1993.sp019823.

Reference Type: BACKGROUND

PMID: 8271208 (View on PubMed)

Gregg EW, Gerzoff RB, Caspersen CJ, Williamson DF, Narayan KM. Relationship of walking to mortality among US adults with diabetes. Arch Intern Med. 2003 Jun 23;163(12):1440-7. doi: 10.1001/archinte.163.12.1440.

Reference Type: BACKGROUND

PMID: 12824093 (View on PubMed)

Fletcher GF, Blair SN, Blumenthal J, Caspersen C, Chaitman B, Epstein S, Falls H, Froelicher ES, Froelicher VF, Pina IL. Statement on exercise. Benefits and recommendations for physical activity programs for all Americans. A statement for health professionals by the Committee on Exercise and Cardiac Rehabilitation of the Council on Clinical Cardiology, American Heart association. Circulation. 1992 Jul;86(1):340-4. doi: 10.1161/01.cir.86.1.340. No abstract available.

Reference Type: BACKGROUND

PMID: 1617788 (View on PubMed)

Physical activity and cardiovascular health. NIH Consensus Development Panel on Physical Activity and Cardiovascular Health. JAMA. 1996 Jul 17;276(3):241-6.

Reference Type: BACKGROUND

PMID: 8667571 (View on PubMed)

American College of Sports Medicine Position Stand. The recommended quantity and quality of exercise for developing and maintaining cardiorespiratory and muscular fitness, and flexibility in healthy adults. Med Sci Sports Exerc. 1998 Jun;30(6):975-91. doi: 10.1097/00005768-199806000-00032.

Reference Type: BACKGROUND

PMID: 9624661 (View on PubMed)

Albright A, Franz M, Hornsby G, Kriska A, Marrero D, Ullrich I, Verity LS. American College of Sports Medicine position stand. Exercise and type 2 diabetes. Med Sci Sports Exerc. 2000 Jul;32(7):1345-60. doi: 10.1097/00005768-200007000-00024.

Reference Type: BACKGROUND

PMID: 10912903 (View on PubMed)

Haskell WL, Lee IM, Pate RR, Powell KE, Blair SN, Franklin BA, Macera CA, Heath GW, Thompson PD, Bauman A. Physical activity and public health: updated recommendation for adults from the American College of Sports Medicine and the American Heart Association. Med Sci Sports Exerc. 2007 Aug;39(8):1423-34. doi: 10.1249/mss.0b013e3180616b27.

Reference Type: BACKGROUND

PMID: 17762377 (View on PubMed)

Earnest CP, Lupo M, Thibodaux J, Hollier C, Butitta B, Lejeune E, Johannsen NM, Gibala MJ, Church TS. Interval training in men at risk for insulin resistance. Int J Sports Med. 2013 Apr;34(4):355-63. doi: 10.1055/s-0032-1311594. Epub 2012 Nov 23.

Reference Type: RESULT

PMID: 23180210 (View on PubMed)

Other Identifiers

R56DK081807

Identifier Type: NIH

Identifier Source: secondary_id

View Link

PBRC 29018

Identifier Type: -

Identifier Source: org_study_id