An interventional study of Dietary Intervention - Ketogenic Diet (KD) and Dietary Intervention - Low-Glycemic Index Diet (CHO-LGI) in Nutrition, Ketogenic Dieting and Low Glycemic Index Diet, sponsored by Poznan University of Physical Education. Active, not recruiting at 1 site in Poland. Open to participants aged 18 Years to 40 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2024-05-16.
Sponsored by Poznan University of Physical Education · Not applicable, Interventional, and Treatment
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.
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.
Poznan University of Physical Education is the lead sponsor of 90 studies on the registry; 27 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Group consuming very low carbohydrate ketogenic diet. The ketogenic diet model was energetically normalized (covered the estimated energy expenditure) and assumed coverage of the daily energy requirement up to 5% of energy from carbohydrates. Proteins were administered in the amount of 1.7 g per kilogram of body mass. The remaining energy needs were covered with fats (fats covered more than 75% of the daily energy requirement). Each of the subjects in this group received 10-day menus.
Other: Dietary Intervention - Ketogenic Diet (KD)
Group consuming carbohydrate, low-glycemic index diet. The carbohydrate diet model with a low glycemic index was energetically normalized (covered the estimated energy expenditure) and assumed coverage of the daily energy requirement of 25% of fat. Proteins were administered in the amount of 1.7 g per kilogram of body mass. The remaining energy needs were covered with carbohydrates (carbohydrates covered about \~55% of the daily energy requirement). The glycemic index of individual meals as well as the daily diet was calculated in accordance with the appropriate recommendations. Each of the subjects in this group received 10-day menus.
Other: Dietary Intervention - Low-Glycemic Index Diet (CHO-LGI)
The experimental procedure for each randomly assigned participant included a 4-week of KD diet.
The experimental procedure for each randomly assigned participant included a 4-week of CHO-LGI diet.
Changes in aerobic capacity following dietary intervention
Time frame: Baseline and after 4 weeks
Changes in CrossFit-specific performance capacity (Fight Gone Bad test) following dietary intervention
The number of correctly performed repetitions of exercises (reps)
Time frame: Baseline and after 4 weeks
Changes in energy substrates utilization following dietary intervention
Fats (g/min) and carbohydrates (g/min) oxidation analysis
Time frame: Baseline and after 4 weeks
Changes in fat mass and fat free mass following dietary intervention
Fat mass (kg) and fat free mass (kg) analysis
Time frame: Baseline and after 4 weeks
Changes of red and white blood cell concentration in blood following dietary intervention
Red blood cells (RBC) \[mln/mm³\] and white blood cells (WBC) \[mln/mm³\] concentration analysis
Time frame: Baseline and after 4 weeks
Changes in blood glucose and hemoglobin concentration following dietary intervention
Hemoglobin (Hb) \[g/dl\] and glucose \[g/dl\] concentration analysis
Time frame: Baseline and after 4 weeks
Changes in blood hematocrit levels following dietary intervention
Hematocrit (HCT) \[%\] level analysis
Time frame: Baseline and after 4 weeks
Changes of testosterone, cortisol, urea, lactate and pyruvate concentration in blood following dietary intervention
Testosterone \[mmol/L\], cortisol \[mmol/L\], urea \[mmol/L\], lactate \[mmol/L\] and pyruvate \[mmol/L\] concentration analysis
Time frame: Baseline and after 4 weeks
Changes of creatine kinase, lactate dehydrogenase, alanine aminotransferase and aspartate aminotransferase activity in blood after following dietary intervention
Creatine kinase \[U/L\], lactate dehydrogenase \[U/L\], alanine aminotransferase \[U/L\] and aspartate aminotransferase \[U/L\] activity analysis
Time frame: Baseline and after 4 weeks
Plan to share: Undecided — Shared data will be exclusively related to the level recorded indicators (anaerobic capacity and specific performance capacity indicators, exercise metabolism, levels of biochemical markers, and body composition), without personal data. The data obtained will be attached to scientific publications, depending on the requirements of the journal.
This study is active, not recruiting, as verified in May 2024. You cannot join it, but the record below documents what was studied.
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Poznan University of Physical Education