Diet Modification, Obesity
Conditions
Keywords
ketogenic diet, carbohydrates, chronic diseases, physical activity, fatigue, mood, wellbeing
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.
Interventions
BEHAVIORALKetogenic diet
The study subjects randomized for this intervention will observe the ketogenic diet, as prescribed by the protocol.
BEHAVIORALExercise HIIT
The study subjects randomized for this intervention will observe the HIIT exercise programme, as prescribed by the protocol.
Sponsors
University of Ostrava
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Masking description
No masking will be used in this study.
Intervention model description
The study subjects will be randomized into four study groups, one of which will be the control group.
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in the time to exhaustion | 12 weeks (baseline + every four weeks) | All study subjects will undergo the Graded Exercise Test, with measuring of the time to exhaustion in minutes. |
| Change in cardiorespiratory variables - oxygen consumption | 12 weeks (baseline + every four weeks) | All study subjects will undergo the Graded Exercise Test, with measuring of the oxygen consumption (L/min). |
| Change in cardiorespiratory variables - heart rate | 12 weeks (baseline + every four weeks) | All study subjects will undergo the Graded Exercise Test, with measuring of the heart rate (beats per minute). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Anthropometrics - body weight | 12 weeks (baseline + every four weeks) | All study subjects will undergo anthropometric assessment of the body weight, measured in kg. |
| Anthropometrics - waist circumference | 12 weeks (baseline + every four weeks) | All study subjects will undergo anthropometric assessment of the waist circumference, measured in cm. |
| Biochemical analysis - capillary blood | 12 weeks (2 times/week) | All study subjects will undergo biochemical analysis of capillary blood - βHB and fasting glukose in mmol/L. |
| InBody (bioimpedance) | 12 weeks (baseline + every four weeks) | All study subjects will undergo antrhropometric assessment of bioimpedance using the InBody device showing the percentage of water and fat in the organism, measured in % of total body weight. |
| Anthropometrics - DXA | 12 weeks (baseline + outcome) | All study subjects will undergo anthropometric assessment of DXA - total abdominal fat, measured in kg. |
| Biochemical analysis - venous blood | 12 weeks (2 times/week) | All study subjects will undergo biochemical analysis of venous blood - oxidative stress, inflammation, total CHO, HDL, LDL, TG, FFA, GL, homocysteine, measured in mmol/L. |
| Anthropometrics - body height | 12 weeks (baseline + every four weeks) | All study subjects will undergo anthropometric assessment of the body height, measured in cm. |
Countries
Czechia
Outcome results
None listed