Clinical trial NCT03934476: The Effects of Lowering Dietary Carbohydrates on Health, Exercise Performance and Wellbeing-related Outcomes
Official title: The Effects of Lowering Dietary Carbohydrates on Health, Exercise Performance and Wellbeing-related Outcomes
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Obesity
Diet Modification
Keywords: ketogenic diet
carbohydrates
chronic diseases
physical activity
fatigue
mood
wellbeing
Lead sponsor: University of Ostrava
Sponsor class: OTHER
First posted: 2019-05-01
Enrollment: 100
Sex: ALL
Minimum age (years): 18
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: The study subjects will be randomized into four study groups, one of which will be the control group.
Primary purpose: PREVENTION

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.

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

Primary outcomes:
measure: Change in the time to exhaustion
timeFrame: 12 weeks (baseline + every four weeks)
measure: Change in cardiorespiratory variables - oxygen consumption
timeFrame: 12 weeks (baseline + every four weeks)
measure: Change in cardiorespiratory variables - heart rate
timeFrame: 12 weeks (baseline + every four weeks)
Secondary outcomes:
measure: Biochemical analysis - capillary blood
timeFrame: 12 weeks (2 times/week)
measure: Biochemical analysis - venous blood
timeFrame: 12 weeks (2 times/week)
measure: Biochemical analysis - venous blood
timeFrame: 12 weeks (2 times/week)
measure: Anthropometrics - body height
timeFrame: 12 weeks (baseline + every four weeks)
measure: Anthropometrics - body weight
timeFrame: 12 weeks (baseline + every four weeks)
measure: Anthropometrics - waist circumference
timeFrame: 12 weeks (baseline + every four weeks)
measure: Anthropometrics - DXA
timeFrame: 12 weeks (baseline + outcome)
measure: InBody (bioimpedance)
timeFrame: 12 weeks (baseline + every four weeks)
Other outcomes:
Locations:
city: Ostrava
country: Czechia
facility: University of Ostrava
state: Moravian-Silesian Region
Study officials:
affiliation: University of Ostrava
name: Lukáš Cipryan, Ass.Prof.,PhDr.,PhD
role: PRINCIPAL_INVESTIGATOR
References:
citation: 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.
citation: 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.
citation: 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.