High Intensity Interval Training, Creatine Intake and Anaerobic Power
Condition: Creatine; High Intensity Interval Training
Study type: Interventional

Summary: 
      Creatine is an ergogenic aid with positive effects on muscle and performance. The aim of the
      study was to determine whether there is a difference between the effects of creatine
      supplementation taken together with Wingate-based HIIT on anaerobic power, leg strength,
      heart rate variability and body composition. In the study, Wingate-based HIIT program was
      applied three days a week for six weeks. Anaerobic power (Wingate anaerobic power test),
      heart rate variability (Polar H10 chest band), leg strength (back and leg dynamometer) and
      body composition (PlusAvis 333) measurements of the participants were made 1 week before the
      training program started and the week after the training program ended. Twenty physically
      active adult men aged 18-30 were voluntarily included for the study. Participants were
      divided into two groups: Wingate-based HIIT with creatine supplementation (K-HIIT) and
      Wingate-based HIIT only (HIIT). As a result of the analysis, it was seen that creatine
      supplementation taken together with wingate-based HIIT had an effect and increased on the
      anaerobic power parameters, peak power, average power and minimum power values, and leg
      strength. In addition, it was determined that heart rate variability parameters improved
      heart rate (HR, beat/min) and low frequency (LF, ms2) values, but did not cause any change in
      body composition. Comparing and investigating the effects of different HIIT methods on
      anaerobic power, leg strength, heart rate variability and body composition will increase the
      generalizability of the study.
    

Detailed description: 
      Despite the time-efficiency of HIIT in inducing chronic physiological adaptation, it depleted
      phosphocreatine stores in the muscle and decrease power output. It has been observed that
      high-intensity exercise performance increases with the increase of intramuscular
      phosphocreatine. It is thought that with creatine supplementation, the rate of
      phosphocreatine resynthesis and mitochondrial transfer of ATP to the cytoplasm may increase.
      This suggests that performing HIIT with creatine supplementation will provide further
      improvement. Therefore, the purpose of this study to compare the effectiveness of HIIT with
      creatine supplement compared to HIIT only. We hypothesized that creatine supplementation
      intake with wingate-based HIIT will positively affect power capacity and performance-related
      parameters.

      The research will be carried out using experimental research design, one of the quantitative
      research methods, to measure the variables and determine the relationship between dependent
      and independent variables. Anaerobic power, heart rate variability, leg strength, and body
      composition measurements of the participants will be made 1 week before the training program
      started and the week after the training program ended.

      The G*power software was utilized in order to determine the appropriate sample size. It has
      been reported that a minimum of 12 participants, 6 in each group, should be included in the
      study (alpha value = 0.05, 1-beta value = 0.80, and effect size = 1.6). Measurement of tests
      and the Wingate-based HIIT program will be conducted in the Performance Laboratory of the
      Faculty of Sports Sciences of Ankara University. Twenty physically active adult men aged
      18-30 years, who had no history of medical and did not use drugs or ergogenic aids, will be
      recruited voluntarily. The ethics committee approval for the study methodology was obtained
      from the Ethics Committee of Ankara University Rectorate (Number: E-56786525-050.04.04/378028
      Decision Number: 2022/02) and it will be carried out in compliance with the Declaration of
      Helsinki's principles. Written inform consents which explain the study to the participant and
      any right and risk will be obtained prior to data collection. Permission for the research to
      be carried out in the Performance Laboratory of the Faculty of Sport Sciences of Ankara
      University will be obtained from the Deanery of the Faculty of Sport Sciences of Ankara
      University. Participants will be divided into two groups as those who will perform
      Wingate-based HIIT with creatine (C-HIIT) (age: 21,78 ± 1,79 years; height: 179.56 ± 8.26 cm;
      weight: 76.86 ± 10.66 kg) and those who will perform only Wingate-based HIIT (HIIT) (age:
      20.167 ± 0,98 years; height: 172.33 ± 9,88 cm ; weight: 66.53 ± 9.51kg ). Out of twenty
      potential participants, only 15 participants agreed to participate in the study (HIIT=6,
      C-HIIT=9) and 5 dropped out because of sport injuries that occured before the study process.

      IBM SPSS 24.0 program (SPSS Inc., Chicago, IL, USA) will be used to statistically analyze the
      data obtained in the study. First of all, the distribution of the data will be evaluated to
      determine the test used to compare the data as parametric or non-parametric. This normality
      distribution assessment will be tested with Shapiro Wilk, as both groups had less than 50
      participants. Determination of the mean difference in within-group statistics will be
      performed with Paired Sample t-Test in data with normal distribution and with Wilcoxon test
      in data where it is not normal. Groups will be expressed as mean ± standard error. American
      Psychological Association (APA) 6.0 style will be used to report statistical differences. The
      alpha value will be accepted as 0.05 in all statistical analysis.

      This study aimed to determine whether there was a difference in the effects of taking
      creatine supplementation with Wingate-based HIIT on anaerobic power, leg strength, heart rate
      variability and body composition.

      The limitation of the current research is that the study will be carried out with a single
      gender. In future studies on the subject, the number of participants can be increased, female
      participants can be included in the research and it can be examined whether there is a
      difference between genders and to increase the generalizability of the study, the effects of
      different HIIT methods on anaerobic power, leg strength, heart rate variability and body
      composition can be compared by investigating. In addition, the trial period may be extended
      as longer periods are needed to see clearer changes in HRV.
    

Intervention name(s): Creatine; HIIT training
Intervention type(s): Dietary Supplement; Other
Intervention description(s): To observe the effects of creatine in the study, 10 g of creatine supplementation was taken only on training days during the study period. Participants used 10 g of creatine monohydrate by dissolved in 200 ml of water. Creatine supplementation was taken in two doses of five grams, 30 minutes before and after training.; In the first three weeks:
Warm-up: Warm-up at 70 rpm for 4 minutes, including 2-3 seconds of maximal sprint at 1.30 and 2.30 minutes Wingate-based HIIT: HIIT 4 sets of 12x15 seconds of maximal repetitions with 15 seconds of passive rest between reps in each set Cool-down: 4 minutes of passive rest between sets
In the last three weeks:
Warm-up: Warm-up at 70 rpm for 4 minutes, including 2-3 seconds of maximal sprint at 1.30 and 2.30 minutes Wingate-based HIIT: HIIT 5 sets of 20x15 seconds of maximal repetitions with 15 seconds of passive rest between reps in each set Cool-down: 4 minutes of passive rest between sets
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: ergogenic aids; HIIT; creatine; performance