Interval Training Plus Creatine Effects on Performance and Glucose Tolerance

NCT02370212 | Completed

• 1 other identifier: H15--00205
• Study Type: interventional
• Target: 18
• Locations: 0 countries
• Sites: N/A

Brief Summary

Recent evidence suggests that high -intensity interval training (HIIT) may be an effective strategy to improve cardiorespiratory fitness, exercise performance, and insulin sensitivity. In addition, creatine (Cr), a nitrogen- containing compound, is widely used to enhance high intensity exercise performance. A seminal study demonstrated that the muscle content of Cr and phosphocreatine (PCr) can be elevated by exogenous Cr. Oral intake of Cr increases the concentration in blood and muscle, and part of the increased muscle Cr is transformed to PCr (a process catalyzed by Cr kinase). Cr supplementation increases total Cr (TCr = Cr + PCr) by \~20%, with the PCr component accounting for 10% of the increase. Combining HIIT and Cr is intriguing for two reasons; first, Cr supplementation improves performance through increasing PCr, PCr recovery, and muscle buffering which may facilitate higher training intensities and therefore greater training adaptations. Secondly, both Cr and HIIT have individually been shown to increase GLUT 4 and insulin sensitivity, suggesting that Cr supplementation may be an adjunct to HIIT for improving glucose control. To date, there have only been two studies investigating the performance effects of Cr combined with HIIT with preliminary positive results. No studies have examined the impact of combined Cr + HIIT on outcomes related to insulin sensitivity. Therefore, the purpose of this research is to examine the combined effects of Cr and HIIT on performance and insulin sensitivity as determined via an oral glucose tolerance test (OGTT) in young healthy adults.

Conditions

Healthy

Keywords

Creatine; interval training; effects on performance

Outcome Measures

Primary Outcomes (1)

• Change from Baseline in exercise performance at 4 weeks

  Assessed by a 50 kilojoule (kJ) time trial test

  4 weeks

Secondary Outcomes (3)

• Change from Baseline in cardiorespiratory fitness

  4 weeks

• Change from Baseline in body composition

  4 weeks

• Change from Baseline in insulin sensitivity

  4 weeks

Study Arms (2)

Creatine

EXPERIMENTAL

Creatine will be ingested after interval training and at supper time on training days and in the morning and afternoon on non-training days (0.05 g/kg body mass of creatine with 0.05 g/kg flavoured dextrose per dose). Both experimental and placebo groups will perform the same high intensity interval training protocols (3x/week for 4 weeks).

Dietary Supplement: Creatine; Other: High intensity interval training

Placebo

PLACEBO COMPARATOR

The placebo will be ingested after interval training and at supper time on training days and in the morning and afternoon on non-training days (0.1 g/kg flavoured dextrose per dose, isocaloric to the creatine). Both experimental and placebo groups will perform the same high intensity interval training protocols (3x/week for 4 weeks).

Dietary Supplement: Placebo; Other: High intensity interval training

Interventions

Creatine DIETARY_SUPPLEMENT

Creatine

Placebo DIETARY_SUPPLEMENT

Placebo

High intensity interval training OTHER

Creatine; Placebo

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Between 18--35 years of age
• Can read, comprehend, and speak English
• Free of diagnosed metabolic disease (e.g., prediabetes, diabetes)
• Willing and able to perform high-intensity exercise training
• Willing and able to consume creatine or placebo supplements over the study period

You may not qualify if:

• Diagnosed metabolic disorder such as diabetes, metabolic syndrome, prediabetes, hypothyroidism, cardiovascular disease or any other condition known to affect metabolism
• Currently engaged in high-intensity interval training \>2 time per week
• Currently taking creatine or other supplements or having taken creatine in the last 12 weeks

Sponsors & Collaborators

• University of British Columbia: lead

MeSH Terms

Interventions

Creatine; High-Intensity Interval Training

Intervention Hierarchy (Ancestors)

Guanidines; Amidines; Organic Chemicals; Amino Acids; Amino Acids, Peptides, and Proteins; Physical Conditioning, Human; Exercise; Motor Activity; Movement; Musculoskeletal Physiological Phenomena; Musculoskeletal and Neural Physiological Phenomena

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 4, 2015
• First Posted: February 24, 2015
• Study Start: March 1, 2015
• Primary Completion: April 1, 2015
• Study Completion: April 1, 2015
• Last Updated: January 20, 2016

Record last verified: 2016-01