Hybrid Exercise Training for Health, Performance and Well-Being (DoIT II)

The Dose-response Effect of High-intensity Interval Neuromuscular Training on Health, Performance and Quality of Life in Overweight/Obese Adults: The DoIT Trial

Observing a lack of research investigating the chronic physiological and psychological responses to this type of exercise training the aim of this study is to investigate the optimal training configurations of DoIT to produce positive effects on health, performance and quality of life markers in sedentary overweight or obese adults aged 30-55 years. The DoIT program will be performed in a small-group setting indoor or outdoor implementing a progressive manner for 12 months and using bodyweight exercises with alternative modes.

This controlled, randomized, four-group, repeated-measures clinical trial will be consisted of the following stages:

1. Initial testing: body weight and height, RMR, daily physical activity (PA), daily nutritional intake.
2. a 4-week adaptive period: based on a dietary analysis, participants will be given a dietary plan (considering the RMR and total daily physical activity related energy expenditure), providing an isocaloric diet over the initial 4-week adaptive period. During this adaptive period, volunteers will also be familiarized with exercises techniques and overload patterns that will be used throughout the study through 4 preparatory sessions.
3. At the end of the adaptation period, participants will participate in assessment procedures (baseline testing) at University facilities.
4. After the adaptive period all participants will be randomly assigned to four groups (control, 1 session/week, 2 sessions/week, 3 sessions/week). The exercise protocols that will be used throughout the 1-year intervention will be consisted of 8-12 neuromotor exercises in circuit fashion applying prescribed time (15-45 sec) of effort and passive recovery intervals.
5. After 12 months of exercise intervention all participants will participate in assessment procedures (post-training testing) at University facilities within 5 days after the completion of the last training session.

All participants will be randomly assigned to the following four groups:

1. Control group (no training)
2. DoIT-1 (1 session/week)
3. DoIT-2 (2 sessions/week)
4. DoIT-3 (3 sessions/week)

Inclusion Criteria:

1. inactivity (no exercise participation for ≥6 months before the study; VO2max <30 ml·kg-1·min-1)
2. age of 30-55 years
3. overweight/obese (BMI 25.0-39.9)
4. body fat percentage for women > 32% and for men > 25%
5. waist circumference for women > 80 cm and for men > 94 cm
6. medical clearance for strenuous physical training
7. no smoking for ≥6 months before the study
8. no diet intervention or usage of nutritional supplements/medications before (≥6 months) and during the study
9. no weight loss greater >10% of body mass before (≤6 months) the study
10. no diagnosis or symptoms of cardiovascular, metabolic, pulmonary, renal, musculoskeletal or mental disorders

Exclusion Criteria:

Participants will be excluded from the study if they:

1. will not participate in ≥80% of total exercise sessions
2. will adhere to a nutritional intervention during the study
3. will modify the habitual physical activity levels during the study