Effects of Creatine Supplementation on Muscle Mass and Function Among Older Women Subjected to Resistance Training
Condition: Muscle Weakness
MeSH terms: Muscle Weakness
Study type: Interventional
Phase: Phase 3

Summary: 
      To determine, in a double blind trial, the effects of creatine supplementation during 12
      weeks on muscle mass and function of community living older women subjected to resistance
      training. Material and methods: Fifty healthy older women will be selected for the study. All
      participants will be subjected to a progressive resistance training program using elastic
      bands and weights, consisting in three sessions per week lasting 1 hour. Participant will be
      randomly allocated in a double blind fashion, to receive creatine 5 g per day or an identical
      placebo. The training and supplementation period will last 12 weeks. At baseline and at the
      end of the study, body composition will be measured by dual energy x-ray absorptiometry,
      rectus femoris cross sectional height and surface will be measured by ultrasound, quadriceps
      strength will be measured in a quadriceps table and 12 minutes' walk will be assessed. The
      main outcome measure will be quadriceps cross sectional height. Expected results: We expect
      that creatine supplementation will increase rectus femoris height over and above the effect
      of resistance training.
    

Detailed description: 
      Healthy women of middle and low socioeconomic level, living in the community and aged between
      60 and 75 years, will be invited to participate in this study.

      At baseline and after signing an informed consent form, the following assessments will be
      carried out:

        1. A complete medical history including medications, previous diseases and surgical
           procedures.

        2. Evaluation of usual physical activity using the International Physical Activity
           Questionnaire (IPAQ) .

        3. Minimental state examination .

        4. Mininutritional assessment .

        5. Measurement of weight, height, waist and hip circumference.

        6. Measurement of body composition by double energy X ray absorptiometry in a General
           Electric iDEXA equipment.

        7. Measurement of rectus femoris cross sectional height using a General Electric LogiQ
           ultrasonographer. Measurements will be made with the participant in supine position and
           the tight relaxed. The mid-point between the superior anterior iliac spine and the
           superior border to the patella will be the measurement point.

        8. Measurement of quadriceps isometric force using a quadriceps table as previously
           described .

        9. Measurement of hand grip strength using a hand grip dynamometer.

       10. Measurement of 12 minutes walking capacity .

      After performing the baseline assessment, participants will be randomized in one of two
      groups, balancing by age and nutritional status, using a double blind design:

        1. The active group will receive creatine 5 g/day in one dose as a powder to be dissolved
           in water

        2. The control group will receive a placebo of similar aspect and taste as creatine.

      The active prescription and the placebo will be identified by a unique numeric code. The
      codes will be known by an external professional, not involved in the research. In case of
      adverse events, the opening of a specific patient code of a will be requested to this
      professional, who will decide the pertinence of the request. Thus, even breaking one code,
      the double blind will be maintained for the rest of participants

      All participants will be incorporated to an exercise training program, that will last 12
      weeks, with three sessions per week. Each exercise session will consist of:

        1. A warm-up period of 15 minutes, consisting in walking and cycling in braked bicycle
           ergometers.

        2. Resistance training of upper and lower limbs, using elastic bands and tubing and free
           weights. Training will be calibrated at 60% of one repetition maximum for each muscle
           group with three sets of 15 repetitions with one minute rest between each set. All
           exercises will be additionally calibrated to be of moderate intensity according to the
           Borg scale. The exercise load will be adapted according to the progression of each
           participant.

        3. An elongation period lasting 10 minutes that will include elongation in mats and
           exercise balls.

      The attendance of participants to each session, their level of engagement with the exercise
      protocol and the overall Borg score will be recorded. All adverse events will be also
      recorded following good clinical practice guidelines Every two weeks, a new supply of the
      research prescription will be delivered. Participants will be requested to return the unused
      sachets to have an approximate assessment of compliance.

      At the end of 12 weeks of intervention, all the assessments done at baseline will be
      repeated.

      All the information of participants will be recorded in encrypted INTERNET databases. Only
      researchers will have access to the information, but participants will be informed about the
      results of all assessments.

      Main outcome measure and calculation of sample size:

      The main outcome will be rectus femoris cross sectional height. According to previously
      published results, this parameter increases from 20 ± 3.2 to 24.3 ± 3.8 mm after a training
      period of 12 weeks . If we expect a 15% difference in rectus femoris cross sectional height
      at the end of the intervention period, we would require 19 participants per group to obtain
      differences with an α of 0.05 and a power of 0.8- Considering an attrition rate of 30% during
      training, we would require 25 participants per group.

      Analysis of results:

      An intention to treat analysis will be performed. Also a safety analysis will also be carried
      out, considering all participants that took at least one dose of creatine or placebo.
      According to the normality of variable distribution, parametric or non-parametric tests will
      be used to analyze differences.
    

Intervention name(s): Resistance exercise training; Creatine
Intervention type(s): Other; Drug
Intervention description(s): All participants will be subjected to resistance training of upper and lower limbs, using elastic bands and tubing and free weights. Training will be calibrated at 60% of one repetition maximum for each muscle group with three sets of 15 repetitions with one minute rest between each set. All exercises will be additionally calibrated to be of moderate intensity according to the Borg scale. The exercise load will be adapted according to the progression of each participant.; Creatine powder 5 g day
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: creatine; resistance training; older women; muscle strength