Low Carbohydrate High Fat Ketogenic vs. Non-ketogenic Diet
Condition: Ketogenic Dieting
Study type: Interventional

Summary: 
      The aim of this paper was to investigate and compare the effects of two iso-energetic
      hypo-caloric ketogenic hyper-ketonemic and non-ketogenic low carbohydrate high fat high
      cholesterol diets on body-composition, muscle strength and hormonal profile in experienced
      resistance-trained middle-aged men. Twenty non-competitive experienced resistance-trained
      middle-aged men were on the supervised calorie maintenance western diet and
      resistance-training regimen for 4 weeks and then divided into ketogenic and non-ketogenic
      groups for 8 weeks period. Keto bodies (β-hydroxybutyrate) levels were measured weekly,
      testosterone and insulin biweekly, strength and body-composition monthly, lipid profile and
      blood sugar level at the beginning and at the end of the study.
    

Detailed description: 
      The primary goal of this research was to investigate and compare the effects of two forms of
      hypo-caloric LCHF high cholesterol ketogenic hyper-ketonemic and non-ketogenic diets on
      muscle strength and body-composition in the experienced resistance-trained middle-aged
      healthy male population, and explore possible advantage of ketogenic state. The secondary
      goal was to examine the rate and magnitude of hormonal changes during the 8 weeks dietary
      phase and their possible impact on the muscle strength and body-composition. It is
      hypothesized that calorie intake is the main variable that influences body-compositional
      changes regardless of the ketogenic state in similar LCHF dieting conditions.

      Four weeks before the experimental procedure participants undertook a detailed medical
      examination and subsequently were familiarized with all testing schedules and new training
      facilities in which they continued supervised training sessions, with equalized exercise
      selection and order for every muscle group as well as for volume and intensity. Participants
      were instructed not to change any of their current eating habits supervised for the total
      energy intake set at the calorie maintenance requirement, until the beginning of the LCHF
      dietary phase of the experiment. After completing 4 weeks of the familiarization phase, the
      subjects were randomized into ketogenic (KG) and non-ketogenic group (NKG). The first group
      received LCHF high-cholesterol ketogenic dietary treatment, and the second group received
      LCHF high-cholesterol non-ketogenic dietary treatment, with the equally reduced calorie
      intake. The experimental dietary phase lasted for 8 weeks without any change in resistance
      training.

      Blood ketones were monitored weekly, hormonal values every 2 weeks, muscle strength and
      body-composition every 4 weeks, and basic blood analysis with lipid profile and blood sugar
      level at the beginning and at the end of the dietary phase of the study Twenty healthy
      non-competitive experienced resistance-trained middle-aged men (Age = 42.7±1.5 years, Body
      height = 181.7±4.6 cm, Body mass (BM) = 88.3±5.8 kg), without any recent medical condition,
      were selected for this research. Inclusion criteria were more than 5 years of experience with
      resistance-training, and a minimum of 2 years of training continuity prior to the study, with
      one repetition maximum (1RM) lower limit for bench press at 100% body weight and for squat at
      130% bodyweight. In addition, including criteria pertaining to dietary habits, was that no
      major change in nutrition regime (prolonged increase or decrease in calories or a
      macronutrient percentage change) was taken in the last 6 months prior to the study. No recent
      injuries and no medical treatment were mandatory conditions for participation in the study.
      After initial consultations, participants were asked to avoid alcohol and training
      stimulants. All participants gave written informed consent for study protocol, approved by
      the Ethical committee of the Faculty of Sport and Physical Education (IRB: 484-2).

      The training was conducted in the same sports facility, supervised by qualified certified
      professionals at the same time of the day, with the beginning between 18 h and 19 h, four
      times per week on working days. After initial strength testing 4 weeks prior to the dietary
      change, subjects training was equalized by the exercise selection, training volume, and
      intensity based on their individual 1RM. Every major muscle group was trained twice per week
      with free weights and auxiliary cable exercises in the 6 - 12 repetitions range and 60 - 90
      seconds between sets and 2 - 3 minutes between exercises. If any of the subjects missed the
      training session it was allowed to complete it on another day of the week. Missing training
      completely meant disqualification from the study. All participants were instructed not to
      perform any additional physical exercise of any type during the study.

      At the beginning of the experimental phase, which followed supervised lead-in calorie
      maintenance habitual diet phase, weekly LCHF ketogenic and non-ketogenic meal plans were
      given to the participants with the additional individual verbal instructions. All supervision
      and guidance were carried through on a weekly base by registered dietitian. Collective
      supervised attainment of the food supply for every next week was conducted from the same
      supermarket brand in 2 locations. Additional individual consultations, if needed, were
      provided for all participants at any time point throughout the study, ensuring compliance to
      the diet. Every participant was provided with the calibrated kitchen scale (Profi Cook PC-KW
      1061) for the duration of the experiment. LCHF diet consisted mainly of meat (beef and veal,
      poultry), fish (salmon, sardines, tuna), butter and coconut oil for cooking, fat cheese,
      flaxseed and olive oil for salad dressing and green vegetables. Whole eggs were mandatory on
      the daily basis insuring intended adequate cholesterol intake. The NKG group obtained their
      additional small amount of carbohydrate intake from brown rice. Protein intake was set to be
      equal for both experimental groups with differences in CHO and fat content. Macronutrient
      ratios for KG and NKG groups were set to 20 %, 5 %, 75 % vs. 20 %, 15 %, 65 % of protein,
      carbohydrates and fat, respectively. Caloric intake for experimental phase was set to cover
      basal metabolism and sedentary activities (BMR times 1.2) for every participant using the
      Mifflin St Jeor equation providing that energy deficit comes primarily from training
      activities. Dietary intake was calculated using the Diet Master Pro 14.4 software.

      All participants were monitored weekly to achieve and sustain blood β-hydroxybutyrate (BHB)
      level of 1 mmol and above in KG and limit it to 0.1 - 0.2 mmol levels in NKG, throughout the
      whole duration of the study. If any of the participants were to cross the marked values of
      the BHB levels in either direction, evaluation and correction of CHO intake would have been
      immediately carried through, and remeasuring was scheduled before the next training session.

      All the biochemical testing, except blood ketone values (BHB), were done on Sunday mornings
      after a complete day of rest from the last training session on Friday's. Blood samples were
      obtained via venipuncture by trained phlebotomists in the morning at 08 h after 12 hours fast
      to avoid diurnal variations. Whole blood was collected, transferred into appropriate tubes
      for obtaining serum and plasma, and subsequently centrifuged at 1,500 g for 15 min at 4°C.
      Resulting serum and plasma were stored at -80°C until analysis which was done on the Roche
      Hitachi Cobas c 311 and c 411 (Roche Diagnostics, Hitachi, Tokyo, Japan) using ECLIA and
      Spectrophotometry methods for testing testosterone, insulin, blood lipid levels (Total
      cholesterol, High density lipoprotein, Low density lipoprotein, Triglycerides) and blood
      glucose levels, while ELISA reader RAYTO RT-2100C (Pioway Medical Lab Equipment, Nanjing,
      China) was used for determining free testosterone levels. All hormones were measured in the
      same assay in duplicate measurements on the same day to avoid compounded inter-assay
      variance. The norm for validity of the measurements was intra-assay variance set to less than
      5% for all analyses.

      The BHB samples were taken from the finger blood sample, using a Precision Xtra™ meter
      (Abbott Diabetes Care, Alameda, CA) and were measured in the late afternoon between 17 h and
      18 h, before collective training. This timing was chosen as optimal to avoid possible
      misreading due to the morning cortisol and training influence.

      Maximal strength was determined via 1RM bench press (BP) and squat (SQ) measurements in
      accordance with International Powerlifting Federation rules. After performing general
      (stationary bicycle) and specific (sets with 50% and 75% of predicted 1RM) warm up, subjects
      had up to 5 attempts to achieve 1RM. Every attempt was accompanied by strong verbal
      encouragement. All testing was done at the same time of day in which subjects had their
      training sessions after two days of rest from the last training.

      Body-composition parameters, lean body mass (LBM) and fat mass (FM) were obtained in the
      morning after an overnight fast on empty stomach using an electric scale, bio-impedance
      device (In Body 720; Biospace Co., Soul, Korea) using the standardized procedure recommended
      by the manufacturer and previous studies. In brief, participants were in a standing position
      with hands and feet placed on the electrodes. Testing was done and monitored by qualified
      laboratory personnel. Participants were instructed to come without any physical effort prior
      to the testing.

      All measurements and testing were done in accordance with Helsinki declaration and rules of
      the Ethic Committee of the Faculty of Sport and Physical Education.

      Basic descriptive statistic (Mean, SD) was performed, following a visual inspection of
      boxplots for identifying outliers. Normality test was performed for confirmation of the
      normality of the data. T test was used to identify differences between lead in and
      experimental diets. Mixed (split plot) ANOVA was used to determine the time, group, and
      treatment x time interactions. When a significant F-value was found, post-hoc with Bonferroni
      adjustment was used for multiple comparisons. Data were reported as mean ± standard
      deviation. The level of significance was set at p < 0.05. The program used for statistical
      analysis was SPSS 19 (IBM).
    

Intervention name(s): Low carb high fat ketogenic dieting; Low carb high fat non-ketogenic dieting
Intervention type(s): Other; Other
Intervention description(s): Macronutrient ratios for low carb high fat ketogenic diet were 20 %, 5 %, 75 % of protein, carbohydrates and fat, respectively. Caloric intake for experimental phase was set to cover basal metabolism and sedentary activities (BMR times 1.2) for every participant using the Mifflin St Jeor equation.; Macronutrient ratios for low carb high fat non-ketogenic diet were 20 %, 15 %, 65 % of protein, carbohydrates and fat, respectively. Caloric intake for experimental phase was set to cover basal metabolism and sedentary activities (BMR times 1.2) for every participant using the Mifflin St Jeor equation.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Ketogenic diet; Testosterone; Insulin; Body-composition; Resistance-training; Middle-aged men