A High-Intensity Exercise Program in Post-Bariatric Patients
Condition: Bariatric Surgery and Physical Activity
Study type: Interventional

Summary: 
      Background: Weight regain is one of the most common problems in bariatric patients. Although
      exercise contributes to maintaining weight, there are currently few studies performed on this
      population.

      Objective: To know the effects of a high-intensity exercise program applied 3 years after
      bariatric surgery on body composition and cardiovascular risk factors.

      Methods: A 37-month follow-up was performed on 21 patients who underwent bariatric surgery,
      in which periodic body composition was evaluated. At month 37, participants were divided into
      an experimental group (EG) and a control group (CG). The EG performed a 5-months of a
      supervised exercise program. At this point physical fitness, glycemia and cholesterolemia
      were also evaluated in the EG. Finally, the EG repeated the evaluations 2-months after the
      end of the program.
    

Detailed description: 
      A total of 40 patients from the Vinalopó-Salud Hospital of Elche (Spain) who underwent
      bariatric surgery between 2010-2013, were recruited. Male and female participants were
      eligible if they complied with the following inclusion criteria: a) absence of cardiovascular
      disease; b) they had not suffered any type of cancer in the 5-year period before surgery; c)
      absence of functional limitations that prevented them from performing the exercise program.

      Before starting the study, an initial interview was conducted with the patients to verify
      that they complied with the inclusion criteria. In this interview, all aspects of the program
      were carefully explained. At the start of the study, all patients who had agreed to
      participate signed an informed consent. This study was conformed to the Declaration of
      Helsinki and approved by the Ethics Committees of the University. Two patients declined to
      participate in the study after the initial interview. Finally, 38 patients started the study
      and 18 finished it.

      One month after surgery, participant's body composition, anthropometric measures and resting
      blood pressure were assessed. These assessments were performed periodically every six months
      until month 19 after surgery. At an average of 37.10 ± 4.35 months of follow-up after
      surgery, they were distributed into two groups, an experimental group (EG; n=10), and a
      control group (CG; n=8). The EG group performed a monitored exercise program, while only the
      evaluations were performed in the CG. At this point, measurements of cardiorespiratory
      fitness and biochemical parameters were added to the previous assessments (anthropometric
      measures and blood pressure) for the EG. An assessment was performed coinciding with the
      start of the exercise program (which lasted 20 weeks), and a final assessment was also
      performed at the end of the program. Finally, the EG was evaluated 2 months after the end of
      the exercise program.

      Body composition, waist and hip circumference, blood pressure and biochemical parameters were
      evaluated between 8:00 ante meridien (AM) and 9:00 AM. Cardiorespiratory fitness was
      evaluated between 4:00 post meridien (PM) and 8:00 PM. Measurements were performed in a
      climatically controlled laboratory, located at 80 m above sea level, in which the relative
      air humidity was maintained between 45-60% and the temperature between 22-24º.

      Body composition, anthropometric measures and cardiovascular risk factors (CVRF) After at
      least 10 hours of fasting, body composition, biochemical parameters and blood pressure were
      measured. Alcohol consumption was restricted for at least 8 hours before the test, while PA
      was forbidden in the 48 hours prior to the test. Participants performed the assessment with
      an empty bladder. Bioimpedance analysis (Tanita, TBF 300A, Tokyo, Japan) was used to
      establish body weight and body composition. Body mass index (BMI) was calculated according to
      the formula: total weight in kilograms divided by squared height in meters (kg·m-2). The
      International Society for the Advancement of Kinanthropometry (ISAK) protocol was used to
      assess height and waist and hip circumference. Blood pressure was measured using a digital
      sphygmomanometer (Microlife WatchBP Home, Heerbrugg, Switzerland), according to established
      recommendations. Capillary blood samples were taken to analyse blood glucose and Total
      Cholesterol (TC) using a portable multi-analyser (Accutrend GCT, Roche Diagnostics, Mannheim,
      Germany).

      Cardiorespiratory fitness The peak oxygen uptake (VO2peak) was determined on a cycle
      ergometer (Technogym Bike Med, Technogym, Gambettola, Italy), using an Oxycon Pro gas
      analysis system (Jaeger, Friedberg, Germany) by adapted protocol from Achten. The protocol
      had two phases: a) a first phase in which the participants performed a 4-minute warm-up at 40
      watts (W), followed by increases of 20 W every 3 minutes, maintaining a cadence of 60
      rotations per minute (RPM) during the whole phase; and, b) a second phase that started when
      the respiratory exchange ratio reached 1.0, and which was aimed to determine the VO2peak.
      This phase consisted of increments of 20 W every minute, maintaining a cadence between 70-80
      RPM, until volitional fatigue. The VO2peak was calculated as the average of the highest 30
      seconds of VO2. The VO2peak was expressed in absolute values (VO2peak ABS) and normalized to
      total body weight (VO2peak/BW) and fat-free mass (VO2peak/FFM).

      Cardiovascular risk (CVR) The SCORE risk charts of the European Society of Cardiology were
      used to calculate CVR. The formula to calculate CVR estimates the 10-year coronary risk using
      TC, systolic blood pressure, gender, age, and smoking status. In addition, CVR was also
      calculated using waist to hip ratio, and waist to height ratio.

      Health-related quality of life The health-related quality of life was measured by the Short
      Form Health Survey 36 (SF-36), in its version adapted to the Spanish context. This
      questionnaire measures physical and mental health through 8 scales, the scores of which are
      transformed to values between 0-100 points, with the highest scores meaning a better
      function. These 8 scales are grouped into two summary components, the physical summary
      component, and the mental summary component, which were calculated according to the reference
      values of the Spanish population, with a mean of 50 and a standard deviation of 10.

      The exercise program lasted 20 weeks, which were distributed in five 4-week blocks. The first
      -block included two weekly sessions, in which the endurance training (ET) and the resistance
      training (RT) for 5 muscle groups (hamstrings, pectorals, quadriceps, latissimus dorsi, and
      gastrocnemius) was combined in the same session. In the second block participants trained 3
      days a week, in two of them a high-intensity interval training (HIIT) was performed, followed
      by RT (biceps and triceps were added to the previous 5 major muscle groups trained), while in
      the third session only the ET was performed. Between the third and fifth block participants
      trained 4 days a week. In two sessions, a HIIT was performed, followed by RT, focusing on
      different muscle groups in each session: a) session 1: pectorals, quadriceps, biceps, and
      hamstrings; b) session 2: dorsal, triceps, gastrocnemius and deltoids. In the other two
      sessions, ET was performed. In all the blocks, 2 days a week of flexibility training were
      carried out.

      The ET (performed on a cycle-ergometer, elliptical and treadmill) was monitored using a heart
      rate (HR) monitor (FT40, Polar, Finland). The RT was performed using resistance machines, and
      training intensity was determined by percentages of 1 maximum repetition which was estimated
      using the Brzycki formula.

      The HIIT consisted of a five-minute warm up, increasing the intensity from 40% of VO2peak to
      60% VO2peak. After this, 20 minutes with bouts of 30 seconds at high intensity (60-95%
      VO2peak) and 30 seconds of active recovery (40% VO2peak), for a total of 10 minutes of
      training at high intensity were performed. Finally, 3 minutes of cool-down at 40% VO2peak
      were performed.
    

Intervention name(s): Physical activity program
Intervention type(s): Other
Intervention model: Sequential Assignment
Intervention model description: two groups (experimental and control) randomly assigned
Masking: None (Open Label)
Primary purpose: Treatment