Impact of Different Types of Exercise Training on Biochemical Markers of Insulin-dependent Patients
Condition: Diabetes Mellitus, Type 1
MeSH terms: Diabetes Mellitus; Diabetes Mellitus, Type 1
Study type: Interventional

Summary: 
      Background: Type 1 diabetes mellitus (T1DM) is characterized by the destruction of β cells
      and consequent loss of insulin secretion due an autoimmune process, being associated with
      increased cardiovascular risk, oxidative stress and inflammation.

      Considering that most people with T1DM do not reach recommended levels of physical activity
      due to concern about the rapid drop in blood sugar and the excuse of "lack of time", shorter
      sessions of exercise that provide several benefits should be encouraged. Thus, this work aims
      to compare the effects of high-intensity interval training (HIIT), strength training (ST) and
      both interventions on several blood markers and functional parameters in T1DM patients.

      Study hypothesis: (1) ST+HIIT will be more beneficial than HIIT, which in turn will be more
      beneficial than ST, on modification of blood levels of pro and anti-inflammatory, pro and
      antioxidant, lipid, renal and glucose metabolism parameters and (2) ST+HIIT will be more
      beneficial than HIIT, which in turn will be more beneficial than ST, on modification of
      functional parameters, body composition and maximal oxygen uptake.
    

Detailed description: 
      Background: Type 1 diabetes mellitus (T1DM), which represents 5-10% of total cases of
      diabetes mellitus, is characterized by the destruction of β cells and consequent loss of
      insulin secretion due a autoimmune process. In diabetic patients, micro (nephropathy,
      neuropathy and retinopathy) and macrovascular (coronary arterial disease, peripheral artery
      disease, stroke) complications are major causes of morbidity and mortality. It is recommended
      that diabetics perform at least 150 minutes (min) per week of moderate aerobic exercise
      divided into at least three days per week, in addition to performing strength training (ST)
      on two or more days of the week. Considering that most people with T1DM do not reach
      recommended levels of physical activity due the fear of hypoglycemia and "lack of time",
      shorter sessions of exercise that provide several benefits should be encouraged. Conversely,
      reviews studies have demonstrated that sessions composed by ST exercises or high-intensity
      interval exercise (HIIE) reduce the risk of hypoglycemia during or after the physical effort,
      when compared with continuous aerobic exercise in T1DM patients, probably via increased
      hepatic glucose production and transitory inhibition of peripheral glucose uptake. The
      high-intensity interval training (HIIT) is known by improving glycemic control and muscular
      adaptations on lipid metabolism in type 2 diabetes mellitus patients, although no studies
      have used this model of training in T1DM individuals.

      Methods: Twenty-seven sedentary T1DM patients (18-40 yo) will be recruited to this randomized
      clinical trial. Volunteers will sign an informed written consent before enrollment in the
      study, which was approved by the Ethics Committee of Federal University of Rio Grande do Sul.
      Initially, all individuals will participate of a control period lasting four weeks, in which
      they will be asked to maintain their habitual level of physical activity and the usual eating
      pattern. After, participants will be randomized in three groups: HIIT, ST or ST+HIIT, each
      lasting ten weeks, with training sessions performed three times/week in cycle ergometers
      and/or weight machines. HIIT protocol will be consisted of 10 x 1 min cycling bouts performed
      ~90% maximal heart rate interspersed with 1 min active recovery. ST will consist of three
      sets performed at the subjects' 10 repetitions maximum load in seven exercises. Participants
      in the ST+HIIT will perform both training protocols in the same session.

      Before control period and before and after interventions, submaximal strength tests,
      cardiorespiratory fitness test, 3-day diet record and blood draws will be assessed/performed.
      Body composition will be evaluated before and after the training period. At the 4th week of
      interventions, the submaximal strength tests and cardiorespiratory fitness test will be
      assessed for adjusting loads.

      According the normality of data, paired Student's t test or Wilcoxon signed rank test will be
      utilized to determine differences before and after control period. The homogeneity of
      variances will be confirmed by Mauchly's test, and a Greenhouse-Geisser correction will be
      applied to the degrees of freedom if the sphericity assumption is violated. Blood outcomes,
      maximal oxygen uptake and strength values will be analyzed using a two-way ANOVA (3
      conditions vs 2 times) with repeated-measures and subsequent Bonferroni post hoc analysis
      when required. Statistical Package for Social Sciences (SPSS 19.0 Inc, Chicago, USA) will be
      utilized and statistical significance set at P < 0.05.
    

Intervention name(s): High-intensity interval training (HIIT); Strength training (ST); ST combined with HIIT (ST+HIIT)
Intervention type(s): Other; Other; Other
Intervention description(s): The HIIT sessions will be performed on cycle ergometers and will be consisted of 10 x 60-s cycling intervals interspersed with 60 s recovery. Individual workloads will be selected to elicit ~90% maximal heart rate attained in the cardiorespiratory fitness test (HRmax). A passive or active recovery will be given among high-intensity stimulus. Each training session will include 3-min warm-up and 2-min cool-down phase performed ~50% (HRmax), totalling 25 min. This intervention will last 10 weeks.; ST protocol will consist of three sets performed at maximum weight that participants could move eight times with good technique in the following exercises: supine bench press (pectoralis major), leg press (quadriceps, biceps femoris, gluteus maximus), lat pulldown (latissimus dorsi), leg extension (quadriceps), shoulder press (deltoids), leg curl (biceps femoris) and abdominal crunch (abdominal muscles). It will be given 1-min rest between series, totalizing approximately 35 min of ST. This intervention will last 10 weeks.; Participants in the ST+HIIT group will execute ST and HIIT (in this order) above described in the same training session, lasting approximately 60 min. This intervention will last 10 weeks.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment