The Effects of Lowering Dietary Carbohydrates on Health, Exercise Performance and Wellbeing-related Outcomes

NCT ID: NCT03934476

Last Updated: 2021-01-25

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 100 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2018-09-01
• Study Completion Date: 2020-12-31

Brief Summary

The aim of the study is to investigate the long-term effects of the ketogenic diet and exercise (including interactions) on health markers, exercise performance and wellbeing outcomes in sedentary overweight individuals.

Detailed Description

Intentional nutritional ketosis induced by the low carbohydrate diet is an intensively discussed topic of many scientific as well as non-scientific discussions throughout the areas of healthy living, the sports sciences and often used now for the prevention and treatment of chronic diseases. It has been demonstrated that long-term low-carbohydrate diet is more effective for weight loss and cardiovascular and metabolic risk factor reduction than a low-fat diet. In light of conflicting theories of best practice surrounding a polarized topic that impacts human health and daily work performance, the primary aim of this research project is to examine how low-carbohydrate ketogenic diets affect health markers, exercise performance and wellbeing outcomes in sedentary overweight individuals. Each study subject will be randomized into one of the four arms of the study and will undergo a 12-week intervention, with the exception of the study subjects in the control group, who will undergo no intervention for the period of 12 weeks.

The project outcomes are of immense importance for the investigator's global human health, focus on a unique holistic perspective and have the potential to contribute towards much-needed adjustments in public health recommendations.

Conditions

Obesity; Diet Modification

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: PREVENTION
• Blinding Strategy: NONE

Study Groups

Ketogenic diet

Ketogenic diet:

• < 50 g carbohydrates - CHO/d (based on the 1-week pre-intervention habitual diet monitoring)
• protein restriction ≤ 1.5 g/kg free-fat mass (FFM)/day.
• fat type intake recommendation:
• natural fats
• trans-FA reduction

Group Type: EXPERIMENTAL

Ketogenic diet

Intervention Type: BEHAVIORAL

The study subjects randomized for this intervention will observe the ketogenic diet, as prescribed by the protocol.

Exercise HIIT (High-Intensity Interval Training)

Exercise intervention:

• HIIT: 5 min warm-up - slow walking, 3 min interval of high-intensity walking (above VT2), 3 min interval of low-intensity walking (40 % VO2peak); 5 min cool-down - slow walking:

Cycle 1

• week 1-3 - 3 sessions/week, total time 31 min/session (4 intervals)
• week 4 - regeneration: only 2 sessions with 2 intervals, keep total time 31 min/session, (+ GXT)

Cycle 2

• week 5-7 - 3 sessions/week, total time 43 min/session (6 intervals)
• week 8 - regeneration: only 2 sessions with 4 intervals, total time 31 min/session, (+ GXT)

Cycle 3

• week 9-11 - 3 sessions/week, total time 55 min/session (8 intervals)
• week 12 - regeneration: only 2 sessions with 6 intervals, total time 43min/session, (+GXT)

Group Type: EXPERIMENTAL

Exercise HIIT

Intervention Type: BEHAVIORAL

The study subjects randomized for this intervention will observe the HIIT exercise programme, as prescribed by the protocol.

Ketogenic diet + Exercise HIIT

Ketogenic diet:

• < 50 g carbohydrates - CHO/d (based on the 1-week pre-intervention habitual diet monitoring)
• protein restriction ≤ 1.5 g/kg free-fat mass (FFM)/day.
• fat type intake recommendation:
• natural fats
• trans-FA reduction

Exercise intervention:

• HIIT: 5 min warm-up - slow walking, 3 min interval of high-intensity walking (above VT2), 3 min interval of low-intensity walking (40 % VO2peak); 5 min cool-down - slow walking:

Cycle 1

• week 1-3 - 3 sessions/week, total time 31 min/session (4 intervals)
• week 4 - regeneration: only 2 sessions with 2 intervals, keep total time 31 min/session, (+ GXT)

Cycle 2

• week 5-7 - 3 sessions/week, total time 43 min/session (6 intervals)
• week 8 - regeneration: only 2 sessions with 4 intervals, total time 31 min/session, (+ GXT)

Cycle 3

• week 9-11 - 3 sessions/week, total time 55 min/session (8 intervals)
• week 12 - regeneration: only 2 sessions with 6 intervals, total time 43min/session, (+GXT)

Group Type: EXPERIMENTAL

Ketogenic diet

Intervention Type: BEHAVIORAL

The study subjects randomized for this intervention will observe the ketogenic diet, as prescribed by the protocol.

Exercise HIIT

Intervention Type: BEHAVIORAL

The study subjects randomized for this intervention will observe the HIIT exercise programme, as prescribed by the protocol.

Control Group

The study subjects in this arm will undergo no dietary changes and no exercise intervention.

Group Type: NO_INTERVENTION

No interventions assigned to this group

Interventions

Ketogenic diet

The study subjects randomized for this intervention will observe the ketogenic diet, as prescribed by the protocol.

Intervention Type: BEHAVIORAL

Exercise HIIT

The study subjects randomized for this intervention will observe the HIIT exercise programme, as prescribed by the protocol.

Intervention Type: BEHAVIORAL

Eligibility Criteria

Inclusion Criteria

• BMI 25.00 - 40.00 kg/m2
• non-smokers
• non-excessive alcohol intake (self-reported, ≥ to 2 drinks/day for men or ≥1 drink/day for women)
• willing to accept random assignment
• low active individuals over the last 1 year, i.e. no specific sports training or regular exercise (up to once a week) and self-reported physical activity < 150 min/week (IPAQ)
• no evidence of liver, renal, metabolic, and cardiopulmonary disease and dis-eases contraindicating physical activity, no cancer, no psychiatric illness
• Physical Activity Readiness Questionnaire (PAR-Q) pass
• body weight stable for the last 2 months and not actively on a weight loss plan
• prediabetes state allowed (impaired fasting glucose level, i.e. 5.6 - 6.9 mmol/l; HbA1c 5.7 - 6.4 %)

Exclusion Criteria

• pregnancy, lactation
• any specific diet (e.g. vegetarian)
• use of hypoglycemic, lipid-lowering, antihypertensive, psychiatric medications or medications known to affect body weight or energy expenditure; any medication not noted allowed if the individual had been stable while taking such medication for at least 3 months prior to baseline data collection

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 60 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of Ostrava

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Lukáš Cipryan, Ass.Prof.,PhDr.,PhD

Role: PRINCIPAL_INVESTIGATOR

University of Ostrava

Locations

University of Ostrava

Ostrava, Moravian-Silesian Region, Czechia

Countries

Czechia

References

Cipryan L, Plews DJ, Ferretti A, Maffetone PB, Laursen PB. Effects of a 4-Week Very Low-Carbohydrate Diet on High-Intensity Interval Training Responses. J Sports Sci Med. 2018 May 14;17(2):259-268. eCollection 2018 Jun.

Reference Type: RESULT

PMID: 29769827 (View on PubMed)

Cipryan L, Kosek V, Garcia CJ, Dostal T, Bechynska K, Hajslova J, Hofmann P. A lipidomic and metabolomic signature of a very low-carbohydrate high-fat diet and high-intensity interval training: an additional analysis of a randomized controlled clinical trial. Metabolomics. 2023 Dec 23;20(1):10. doi: 10.1007/s11306-023-02071-1.

Reference Type: DERIVED

PMID: 38141101 (View on PubMed)

Cipryan L, Litschmannova M, Maffetone PB, Plews DJ, Dostal T, Hofmann P, Laursen PB. Very Low-Carbohydrate High-Fat Diet Improves Risk Markers for Cardiometabolic Health More Than Exercise in Men and Women With Overfat Constitution: Secondary Analysis of a Randomized Controlled Clinical Trial. Front Nutr. 2022 May 23;9:867690. doi: 10.3389/fnut.2022.867690. eCollection 2022.

Reference Type: DERIVED

PMID: 35677551 (View on PubMed)

Cipryan L, Dostal T, Litschmannova M, Hofmann P, Maffetone PB, Laursen PB. Effects of a Very Low-Carbohydrate High-Fat Diet and High-Intensity Interval Training on Visceral Fat Deposition and Cardiorespiratory Fitness in Overfat Individuals: A Randomized Controlled Clinical Trial. Front Nutr. 2021 Dec 21;8:785694. doi: 10.3389/fnut.2021.785694. eCollection 2021.

Reference Type: DERIVED

PMID: 34993222 (View on PubMed)

Other Identifiers

18-08358S

Identifier Type: OTHER_GRANT

Identifier Source: secondary_id

OU-PdF-GACR-LCHF diet

Identifier Type: -

Identifier Source: org_study_id