Different Order of Concurrent Training on Improving Visceral Adipose Tissue and Insulin Resistance.

Background: Visceral adipose tissue (VAT) accumulation is highly linking with cardiovascular diseases and insulin resistance. A combination of aerobic exercise (AE) and resistance exercise (RE) was an effective strategy to improve VAT and insulin resistance; however, no current evidence displayed whether the different orders of concurrent training (AE preceding RE or RE preceding AE) influence the effects on VAT reduction and insulin resistance improvement.

Purposes: The purpose of one-year project is to compare the effect of different intrasession exercise order of AE and RE during concurrent training on reducing VAT and improving insulin resistance for inactive middle-age community residents with obesity.

Methods: Purposive sampling will be used to enroll community residents aged 40-64 years with inactive habit and body fat percentage ≧ 25% for male and ≧ 30% for female in Tainan. Eligible participants will be stratified by sex and age (40-55years and 56-64 years) then block randomly divided into training group of AE preceding RE, RE preceding AE or a control group. The exercise training program will under supervision lasting 16 weeks with 3 times per week. The concurrent training prescription consist of AE 30 minutes and RE 15 minutes per session. A 5-minute interval between two exercise modalities. The control group will follow their primary lifestyle without exercise intervention. All participants will be evaluated outcomes for two time points including baseline (T0) and after 16-week intervention (T1). The primary outcomes are VAT and insulin resistance. VAT is measured by body composition analyzer and insulin resistance is calculate from fasting glucose and insulin level in blood samples. A two-way ANOVA with repeated measures will be performed to compare changes of outcome variables over the intervention period.

Relevance to clinical practice: The results of this project can assist health professionals to know how to properly prescribe concurrent training of AE and RE to achieve the greatest effects on VATreduction and insulin resistance improvement for middle-age residents with obesity.

Inclusion criteria

• 40 to 64 years old.
• body fat percentage ≧ 25% for male and ≧ 30% for female.
• with inactive habit (≤ 3 days of physical activity per week and ≤ 30 min per session).
• can communicate in Mandarin or Taiwanese.

Exclusion criteria

• with recent unstable conditions in which had potential risk on exercise including stroke, cardiovascular and respiratory diseases, handicap, pregnancy.
• with any contraindications to body composition analyzer measurement including body embed pacemakers and artificial metal joints, amputated hands or feet.
• cannot corporate with either examination or intervention.
• use psychotropic or appetite-regulating medicine.
• under oral hopoglycemic agent or insulin treatment.