Crossfit, Ketogenic Dieting, Low Glycemic Index Diet, Nutrition, Sport
Conditions
Keywords
Sports Nutrition, Ketogenic Diet, Low Glycemic Index Diet, Crossfit, Physical capacity, Performance, Exercise metabolism, Training support
Brief summary
The purpose of the presented study was to assess the influence of Ketogenic (KD) and a carbohydrate diet with a low glycemic index (CHO-LGI) of a 4-week diet on physical and specific performance capacity, exercise metabolism, as well as concentrations of the selected biochemical blood markers in Crossfit- trained athletes, in a randomised and parallel trial.
Detailed description
The impact of various dietary strategies, including the alternative ketogenic diet - recently popular among strength athletes, has not been unequivocally assessed in the high-intensity sport disciplines that Crossfit belongs to. There is also a lack of data in these disciplines about the potential longer adaptation of athletes to the very low carbohydrate intake resulting from the ketogenic diet and its impact in high-intensity Crossfit training. Therefore, the purpose of this study was the assessment of the influence of a 4-week KD and a CHO-LGI diet on physical and specific performance capacity, exercise metabolism, as well as concentrations of the selected biochemical blood markers in Crossfit- trained athletes, in a randomised and parallel trial.
Interventions
OTHERDietary Intervention - Ketogenic Diet (KD)
The experimental procedure for each randomly assigned participant included a 4-week of KD diet.
OTHERDietary Intervention - Low-Glycemic Index Diet (CHO-LGI)
The experimental procedure for each randomly assigned participant included a 4-week of CHO-LGI diet.
Sponsors
Poznan University of PhysED
Poznan University of Life Sciences
Poznan University of Physical Education
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
* written consent to participate, * a current medical clearance to practice sports, * training experience: at least 2 years, * minimum of 4 workout sessions (Crossfit) a week.
Exclusion criteria
* current injury, * any health-related contraindication, * declared general feeling of being unwell, * unwilling to follow the study protocol, * smoking, illicit drug use, alcohol consumption greater than 1-2 drinks/week, dietary supplements use less than 3 weeks before the study, * females- being pregnant or planning to become pregnant during the study.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in aerobic capacity following dietary intervention | Baseline and after 4 weeks | — |
| Changes in CrossFit-specific performance capacity (Fight Gone Bad test) following dietary intervention | Baseline and after 4 weeks | The number of correctly performed repetitions of exercises (reps) |
| Changes in energy substrates utilization following dietary intervention | Baseline and after 4 weeks | Fats (g/min) and carbohydrates (g/min) oxidation analysis |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Changes in blood hematocrit levels following dietary intervention | Baseline and after 4 weeks | Hematocrit (HCT) \[%\] level analysis |
| Changes in fat mass and fat free mass following dietary intervention | Baseline and after 4 weeks | Fat mass (kg) and fat free mass (kg) analysis |
| Changes of creatine kinase, lactate dehydrogenase, alanine aminotransferase and aspartate aminotransferase activity in blood after following dietary intervention | Baseline and after 4 weeks | Creatine kinase \[U/L\], lactate dehydrogenase \[U/L\], alanine aminotransferase \[U/L\] and aspartate aminotransferase \[U/L\] activity analysis |
| Changes of testosterone, cortisol, urea, lactate and pyruvate concentration in blood following dietary intervention | Baseline and after 4 weeks | Testosterone \[mmol/L\], cortisol \[mmol/L\], urea \[mmol/L\], lactate \[mmol/L\] and pyruvate \[mmol/L\] concentration analysis |
| Changes of red and white blood cell concentration in blood following dietary intervention | Baseline and after 4 weeks | Red blood cells (RBC) \[mln/mm³\] and white blood cells (WBC) \[mln/mm³\] concentration analysis |
| Changes in blood glucose and hemoglobin concentration following dietary intervention | Baseline and after 4 weeks | Hemoglobin (Hb) \[g/dl\] and glucose \[g/dl\] concentration analysis |
Countries
Poland
Outcome results
None listed