Dietary carbohydrate and substrate oxidation during exercise

  • Research type

    Research Study

  • Full title

    The effect of dietary carbohydrate manipulation following glycogen depleting exercise on substrate oxidation at rest and during exercise

  • IRAS ID

    192241

  • Contact name

    Gareth A Wallis

  • Contact email

    g.a.wallis@bham.ac.uk

  • Sponsor organisation

    University of Birmingham

  • Clinicaltrials.gov Identifier

    NCT02605291

  • Duration of Study in the UK

    1 years, 6 months, 30 days

  • Research summary

    Reducing body fat is desirable for many people, be that for benefits to health or for improving sporting performance. One way to help reduce body fat is to expend more energy from the oxidation of fat as a fuel (sometimes referred to as ‘fat-burning’). Exercise is one way to increase fat oxidation. The extent to which exercise facilitates the use of fat as a fuel may be influenced by an individual’s dietary intake. A diet rich in carbohydrates may act to reduce the oxidation of fat in favour of the use of carbohydrate as fuel for exercise. In contrast, diets lower in carbohydrates can increase the use of fat as a fuel during exercise.
    It could be that altering dietary carbohydrate intake exerts its effect on fat oxidation through changes in the level of carbohydrate stored in muscle (this is known as muscle glycogen). However, the relationship between dietary carbohydrate intake, muscle glycogen levels and fat oxidation during exercise has not been systematically studied and the present study is the first step towards addressing this knowledge gap.

    We will investigate the hypothesis that manipulating dietary carbohydrate intake by providing diets low, moderate or high in carbohydrate will result in graded levels of muscle glycogen ranging from very low (~30-40% of normal), reduced (~60-70% of normal) and normal. The current study will provide important validation of the dietary carbohydrate manipulation strategy designed such that future studies using this dietary approach can be performed to investigate its influence on fat oxidation during exercise with confidence that muscle glycogen levels have been appropriately altered.

    Collectively, by studying the links between dietary carbohydrate, muscle glycogen and fat oxidation during exercise we hope to develop further understanding of how diet and exercise strategies can be combined to assist with the management of body fat levels.

  • REC name

    West Midlands - South Birmingham Research Ethics Committee

  • REC reference

    15/WM/0452

  • Date of REC Opinion

    13 Jan 2016

  • REC opinion

    Further Information Favourable Opinion