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ObesityNCT05107583

Effects of Pre-exercise Carbohydrate Restriction Relative to Fasting on Metabolism, Appetite, and Energy Intake in Healthy Males.

A study testing Low-Carbohydrate Pre-Exercise Meal, High-Carbohydrate Pre-Exercise Meal and Fasted Exercise in people with Obesity and Metabolic Syndrome, run by Nottingham Trent University at 2 sites in United Kingdom.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

This study will compare the metabolic, appetite, energy intake, and perceptual responses to a bout of exercise completed in the evening after after a low-carbohydrate lunch meal (<10% carbohydrate content / 0.2 g/kg carbohydrate; LO-CHO), with the responses to exercise performed after a lunch meal containing a high… Read more about this study

Who is it for?
Ages 18 to 40 years, men onlyHealthy volunteers can take part
Conditions the study is for
Obesity, Metabolic Syndrome
What is being tested?
Low-Carbohydrate Pre-Exercise Meal, High-Carbohydrate Pre-Exercise Meal and Fasted Exercise
Could I receive a placebo?
No, everyone receives an active treatment
How many people
12 participants
Where
2 sitesUnited Kingdom
Study dates
1 Sep 2021to 30 Jun 2022
Phase
Interventional
Are there results?
None posted in the registry

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 40 years
  • Men only
  • Healthy volunteers accepted
  • Adult

Who may be able to join

  • Non-smokers (due to the well-known impact of smoking on appetite.
  • Not currently on a weight management program or have an unusual eating pattern (i.e., extended fasting periods >8 h other than overnight).
  • Have maintained a stable weight for 6 months (self-reported).
  • No history of gastric, digestive, cardiovascular or renal disease (self-reported).

Who cannot join

  • Severe food allergies, dislike or intolerance of study foods or drinks.
  • Currently undergoing a lifestyle intervention (structured diet or exercise).
  • Diagnosis of a condition or currently undergoing treatment therapy known to affect glucose or lipid metabolism (e.g., type-2 diabetes, taking statins), or contraindications to exercise.
  • Use of medication or supplements that may affect hormone concentrations and/or substrate metabolism.
  • Excessive alcohol consumption (>14 units/week).
  • Intensive training schedule (>10 hours/week).

Trial locations and contacts

2 sites in 1 country.

United Kingdom2 sites
  • Loughborough University

    Loughborough, Leicestershire, LE11 3TU

  • Nottingham Trent University

    Nottingham, Nottinghamshire, NG11 8NS

Other trials in United Kingdom

About this study

Official title: Comparing the Effects of a High- and Low-carbohydrate Pre-exercise Meal Relative to Fasting on Exercise Metabolism, Subsequent Appetite, and Energy Intake in Healthy Males.

This study will compare the metabolic, appetite, energy intake, and perceptual responses to a bout of exercise completed in the evening after after a low-carbohydrate lunch meal (<10% carbohydrate content / 0.2 g/kg carbohydrate; LO-CHO), with the responses to exercise performed after a lunch meal containing a high carbohydrate content (~60% carbohydrate content / 2.2 g/kg carbohydrate; HI-CHO), and after skipping lunch and fasting for 8 hours since breakfast (FAST).

Read the detailed description

Regular exercise is known to be a successful strategy for improving several facets of health and maintaining body weight. However, many people are not engaging in enough exercise, and some may not be achieving maximum benefits from the exercise that they already do. Performing exercise in the overnight fasted state has been shown to reduce energy intake over the course of a single day, without any compensatory reductions in free-living energy expenditure. Despite these promising findings, it is likely that not every member of the population is logistically able to perform exercise in the morning due to various work, family and social commitments, and exercise in the evening may be a logical alternative for these individuals.

Studies have found that exercise performed after an overnight fast may incur superior improvements in insulin sensitivity in lean individuals (Van Proeyen et al., 2010), and individuals with overweight or obesity (Edinburgh et al., 2020), compared to exercising after breakfast. These superior improvements may be mediated, in part, by an increased mobilisation and oxidation of endogenous lipid stores. Additionally, overnight fasted exercise may result in a more negative energy balance than exercising after breakfast (Bachman et al., 2016; Edinburgh et al., 2019). We recently examined whether exercise performed in the evening following an extended period of fasting (7 h) would induce similar responses to overnight fasted exercise regarding substrate oxidation patterns and subsequent energy intake (manuscript in preparation - NCT04742530). This research question was important, as we speculate that a large proportion of the population are likely unable to perform exercise in the morning after an overnight fast due to various logistical barriers. Therefore fasting prior to evening exercise could act as an alternative for these individuals.

We found that compared to consuming a carbohydrate-containing meal 2 h prior, fasting before evening exercise resulted in elevated fat oxidation rates during exercise, but was accompanied by compensatory eating at dinner. Additionally, participants reported that fasting throughout the afternoon was difficult. The long-term efficacy of fasted evening exercise may, therefore, be limited by increased hunger and compensatory energy intake.

Consuming a meal lower in carbohydrate and higher in protein and/or fat can increase rates of fat oxidation during exercise (Rowlands \& Hopkins, 2002; Oliviera et al., 2021). Protein is also the most satiating macronutrient, and high-protein diets are associated with reductions in energy intake. Consuming a high-protein pre-exercise meal compared to a typical high-carbohydrate meal also led to greater exercise-induced elevations in hormones typically associated with increased satiety and reduced hunger: peptide tyrosine-tyrosine (PYY) and glucagon-like peptide-1 (GLP-1) (Oliviera et al., 2021). Therefore, consuming a meal with a low carbohydrate content and higher protein content before exercise, rather than completely fasting, could be utilised to enhance the metabolic responses to exercise, whilst simultaneously managing appetite and subsequent energy intake. Further research is needed to fully understand the metabolic and appetite-related effects of a low-carbohydrate, higher-protein meal prior to exercise in the evening, compared to a typically consumed higher-carbohydrate meal and complete fasting.

Being tested
Low-Carbohydrate Pre-Exercise Meal, High-Carbohydrate Pre-Exercise Meal, Fasted Exercise
Keywords
Fasted exercise, Low-carbohydrate, High-protein, Appetite, Energy Intake, Metabolism
Medical subject headings
Obesity, Metabolic Syndrome

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Low-Carbohydrate Pre-Exercise MealBehavioural

    Sixty minutes of cycling at 60% VO2peak will take place on a stationary bicycle ergometer at 16:00, after having consumed a low-carbohydrate lunch meal (<10% carbohydrate; 35% estimated energy requirements) 2.5 hours prior.

  • High-Carbohydrate Pre-Exercise MealBehavioural

    Sixty minutes of cycling at 60% VO2peak will take place on a stationary bicycle ergometer at 16:00, after having consumed a high-carbohydrate lunch meal (~2.2 g/kg carbohydrate; 35% estimated energy requirements) 2.5 hours prior.

  • Fasted ExerciseBehavioural

    Sixty minutes of cycling at 60% VO2peak will take place on a stationary bicycle ergometer at 16:00, after having skipped lunch, and having consumed nothing other than plain water since breakfast (08:00; 25% estimated energy requirements). Exercise will therefore commence after an 8 hour period of fasting.

Study groups in NCT05107583
Study groupRoleWhat they receive
Low-Carbohydrate Pre-Exercise MealExperimentalParticipants will consume a low-carbohydrate (<10% carbohydrate) lunch meal at 13:30 - 2.5 hours prior to commencing exercise at 16:00.
Receives: Behavioral: Low-Carbohydrate Pre-Exercise Meal
High-Carbohydrate Pre-Exercise MealExperimentalParticipants will consume a high-carbohydrate (~2.2 g/kg carbohydrate) lunch meal at 13:30 - 2.5 hours prior to commencing exercise at 16:00.
Receives: Behavioral: High-Carbohydrate Pre-Exercise Meal
Fasted ExerciseExperimentalParticipants will skip lunch, and continue fasting since breakfast (08:00) before commencing exercise at 16:00. Therefore, exercise will commence after an 8 hour period of fasting.
Receives: Behavioral: Fasted Exercise

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Fat Oxidation Rate During Steady-State Exercise.

    Measurements of VO2 and VCO2 during a 60 minute steady state bout of cycling to determine rates of fat oxidation.

    Measured: Throughout the 60-minute steady-state bout of cycling

Secondary outcomes (17)
  1. Voluntary energy intake (Kilocalories) at a laboratory-based test meal.

    A laboratory-based dinner meal consisting of pasta, tomato sauce and olive oil will be provided to participants in excess of expected consumption. Participants will be permitted 20 minutes to eat as much or as little as they desire, until 'comfortably full and satisfied'.

    Measured: 60 minutes following the end of the exercise session.

  2. Visual Analogue Scale for Subjective Ratings of Appetite.

    Time-course of subjective ratings of hunger between breakfast provision and one hour after consuming lunch, measured using an appetite visual analogue scale. The scale is divided into subscales of different appetite perceptions including: hunger, fullness, desire to eat and prospective food consumption. Each subscale is rated on a 100mm scale (i.e. from 0 - 100), with a rating of 100 fully supporting the perception and a rating of 0 fully opposing the perception.

    Measured: Baseline, 1 hour, 1.75 hours, 2.75 hours, 3 hours, 3.5 hours (mid-exercise), 4 hours, 5 hours.

  3. Acylated ghrelin

    Time-course of acylated ghrelin plasma concentrations across experimental trials.

    Measured: Baseline, 1 hour, 1.75 hours, 2.75 hours, 3 hours, 3.5 hours (mid-exercise), 4 hours, 5 hours.

  4. Peptide tyrosine-tyrosine (PYY)

    Time-course of PYY plasma concentrations across experimental trials.

    Measured: Baseline, 1 hour, 1.75 hours, 2.75 hours, 3 hours, 3.5 hours (mid-exercise), 4 hours, 5 hours.

  5. Glucagon-like peptide-1 (GLP-1)

    Time-course of GLP-1 plasma concentrations across experimental trials.

    Measured: Baseline, 1 hour, 1.75 hours, 2.75 hours, 3 hours, 3.5 hours (mid-exercise), 4 hours, 5 hours.

  6. Glucose

    Time-course of glucose plasma concentrations across experimental trials.

    Measured: Baseline, 1 hour, 1.75 hours, 2.75 hours, 3 hours, 3.5 hours (mid-exercise), 4 hours, 5 hours.

  7. Insulin

    Time-course of insulin plasma concentrations across experimental trials.

    Measured: Baseline, 1 hour, 1.75 hours, 2.75 hours, 3 hours, 3.5 hours (mid-exercise), 4 hours, 5 hours.

  8. Non-esterified fatty-acids (NEFA)

    Time-course of NEFA plasma concentrations across experimental trials.

    Measured: Baseline, 1 hour, 1.75 hours, 2.75 hours, 3 hours, 3.5 hours (mid-exercise), 4 hours, 5 hours.

  9. Glycerol

    Time-course of glycerol plasma concentrations across experimental trials.

    Measured: Baseline, 1 hour, 1.75 hours, 2.75 hours, 3 hours, 3.5 hours (mid-exercise), 4 hours, 5 hours.

  10. Rating of Perceived Exertion (RPE).

    RPE will be measured at 10-minute intervals throughout the 60-minute exercise period on a 6-20 RPE scale. The participant will point to the value that corresponds to their current perceived exertion (6 being no exertion at all; 20 being maximal exertion).

    Measured: Throughout the 60-minute steady-state bout of cycling.

  11. Pre-exercise Subjective Feelings.

    A single questionnaire to assess pre-exercise subjective feelings will be measured using a visual analogue scale. The scale is divided into subscales of different feelings including: motivation, readiness, tiredness, nausea, and energetic. Each subscale is rated on a 100mm scale (i.e. from 0 - 100), with a rating of 100 fully supporting the perception and a rating of 0 fully opposing the perception.

    Measured: Immediately before the exercise session.

  12. Enjoyment of the Exercise Bout.

    A shortened version of The Physical Activity Enjoyment Scale (PACES) will be completed to gauge enjoyment of the exercise sessions. A scale from 1-7 will be used for eight feelings. The participant will circle the value that corresponds to which (6 being no exertion at all; 20 being maximal exertion).

    The scale is divided into bipolar subscales of different feelings including: enjoyment, liking, pleasure, fun, pleasantness, interest, engagement and task absorption . Each subscale is rated on a 1-7 bipolar scale (i.e. from 1 - 7), with a rating of 1 fully supporting the feeling on the left-hand side of the subscale, and a rating of 7 fully supporting the feeling on the right-hand side of the subscale. For three subscales, a positive feeling is placed at 7, and for four subscales, a negative feeling is placed at 7 (reverse scored).

    Measured: Immediately following the end of the exercise session.

  13. Carbohydrate Oxidation Rate During Steady-State Exercise

    Measurements of VO2 and VCO2 during a 60 minute steady state bout of cycling to determine rates of carbohydrate oxidation

    Measured: Throughout the 60-minute steady-state bout of cycling

  14. Rate of Energy Expenditure During Steady-State Exercise

    Measurements of VO2 and VCO2 during a 60 minute steady state bout of cycling to determine rates energy expenditure.

    Measured: Throughout the 60-minute steady-state bout of cycling

  15. Carbohydrate Oxidation Rate At Rest

    Measurements of VO2 and VCO2 during at rest during experimental trials to determine rates of carbohydrate oxidation.

    Measured: Baseline, 1 hour, 1.75 hours, 2.75 hours, 5 hours

  16. Fat Oxidation Rate At Rest

    Measurements of VO2 and VCO2 during at rest during experimental trials to determine rates of fat oxidation.

    Measured: Baseline, 1 hour, 1.75 hours, 2.75 hours, 5 hours

  17. Rate of Energy Expenditure At Rest

    Measurements of VO2 and VCO2 during at rest during experimental trials to determine rates of energy expenditure.

    Measured: Baseline, 1 hour, 1.75 hours, 2.75 hours, 5 hours

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted4 Nov 2021
  2. Study start1 Sep 2021
  3. Primary completion30 Jun 2022
  4. Study completion30 Jun 2022

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Basic science
Allocation
Randomised
Intervention model
Crossover
Model description
The study design is a randomised, controlled, crossover design in which participants undertake three exercise conditions in a randomised order with at least a seven day period in between trials.
Masking
Single blind
Who is masked
Participant
Enrolment
12 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT05107583
Sponsor's protocol ID
TS_PreExCHO_2021
Status last verified
Sep 2022
First submitted
12 Aug 2021
Last updated
14 Sep 2022
Results posted
No
Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
Individual data sharing
Undecided

Publications

  • Edinburgh RM, Bradley HE, Abdullah NF, Robinson SL, Chrzanowski-Smith OJ, Walhin JP, Joanisse S, Manolopoulos KN, Philp A, Hengist A, Chabowski A, Brodsky FM, Koumanov F, Betts JA, Thompson D, Wallis GA, Gonzalez JT. Lipid Metabolism Links Nutrient-Exercise Timing to Insulin Sensitivity in Men Classified as Overweight or Obese. J Clin Endocrinol Metab. 2020 Mar 1;105(3):660-76. doi: 10.1210/clinem/dgz104.

    PubMed 31628477
  • Van Proeyen K, Szlufcik K, Nielens H, Pelgrim K, Deldicque L, Hesselink M, Van Veldhoven PP, Hespel P. Training in the fasted state improves glucose tolerance during fat-rich diet. J Physiol. 2010 Nov 1;588(Pt 21):4289-302. doi: 10.1113/jphysiol.2010.196493.

    PubMed 20837645
  • Edinburgh RM, Hengist A, Smith HA, Travers RL, Betts JA, Thompson D, Walhin JP, Wallis GA, Hamilton DL, Stevenson EJ, Tipton KD, Gonzalez JT. Skipping Breakfast Before Exercise Creates a More Negative 24-hour Energy Balance: A Randomized Controlled Trial in Healthy Physically Active Young Men. J Nutr. 2019 Aug 1;149(8):1326-1334. doi: 10.1093/jn/nxz018.

    PubMed 31321428
  • Bachman JL, Deitrick RW, Hillman AR. Exercising in the Fasted State Reduced 24-Hour Energy Intake in Active Male Adults. J Nutr Metab. 2016;2016:1984198. doi: 10.1155/2016/1984198. Epub 2016 Sep 21.

    PubMed 27738523
  • Rowlands DS, Hopkins WG. Effects of high-fat and high-carbohydrate diets on metabolism and performance in cycling. Metabolism. 2002 Jun;51(6):678-90. doi: 10.1053/meta.2002.32723.

    PubMed 12037719
  • Oliveira CLP, Boule NG, Berg A, Sharma AM, Elliott SA, Siervo M, Ghosh S, Prado CM. Consumption of a High-Protein Meal Replacement Leads to Higher Fat Oxidation, Suppression of Hunger, and Improved Metabolic Profile After an Exercise Session. Nutrients. 2021 Jan 5;13(1):155. doi: 10.3390/nu13010155.

    PubMed 33466462
  • Kendzierski, D., & DeCarlo, K. J. (1991). Physical Activity Enjoyment Scale: Two Validation Studies. Journal of Sport and Exercise Psychology, 13(1), 50-64. doi:10.1123/jsep.13.1.50.

  • Rothschild JA, Kilding AE, Broome SC, Stewart T, Cronin JB, Plews DJ. Pre-Exercise Carbohydrate or Protein Ingestion Influences Substrate Oxidation but Not Performance or Hunger Compared with Cycling in the Fasted State. Nutrients. 2021 Apr 14;13(4):1291. doi: 10.3390/nu13041291.

    PubMed 33919779

Questions about this trial

What is this clinical trial studying?

A study testing Low-Carbohydrate Pre-Exercise Meal, High-Carbohydrate Pre-Exercise Meal and Fasted Exercise in people with Obesity and Metabolic Syndrome, run by Nottingham Trent University at 2 sites in United Kingdom.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 4 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 14 Sep 2022. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 2 sites in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Fat Oxidation Rate During Steady-State Exercise. (time frame: Throughout the 60-minute steady-state bout of cycling). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT05107583, which also lists 8 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 14 Sep 2022.

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