Working… Menu

Effects of Ketogenic Diet on Body Composition and Performance in Soccer Players

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT04078971
Recruitment Status : Completed
First Posted : September 5, 2019
Last Update Posted : September 6, 2019
Information provided by (Responsible Party):
Antonio Paoli, University of Padova

Brief Summary:
A ketogenic diet (KD) is a nutritional approach, usually adopted for weight loss, that restricts daily carbohydrates under 30 g/day. KD showed contradictory results on sport performance, whilst no data are available on team sports. The investigators will investigate the influence of a KD on different parameters in soccer players

Condition or disease Intervention/treatment Phase
Athletic Performance Other: Western diet Other: ketogenic diet Not Applicable

Detailed Description:
Sixteen semi-professional soccer players will be randomly assigned to a ketogenic diet (KD n=8) or to a western diet (WD n=8). Diets contain the same amount of protein (1.8g/Kg body weight/day). Body weight and body composition will be measured by dual energy x-ray absorptiometry (DXA) and bioelectrical impedance analysis (BIA). Resting energy expenditure (REE), respiratory exchange ratio (RER), cross sectional area (CSA) and isometric muscle strength of quadriceps, counter movement jump (CMJ) and yoyo intermittent recovery test will be measured.

Layout table for study information
Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 16 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Intervention Model Description: It is single blind, parallel arms study
Masking: Double (Investigator, Outcomes Assessor)
Masking Description: Treatment and control were masked with A and B
Primary Purpose: Basic Science
Official Title: Effects of a Very Low Carbohydrate Ketogenic Diet on Body Composition, Muscle Strength, Muscle Area, Metabolism and Performance in Semi-professional Soccer Players
Actual Study Start Date : May 2, 2018
Actual Primary Completion Date : October 30, 2018
Actual Study Completion Date : December 15, 2018

Arm Intervention/treatment
Experimental: Ketogenic diet
Ketogenic diet: less than 30 g/day of carbohydrate. Subjects can eat beef, veal, poultry, fish, raw and cooked vegetables without restriction, cold cuts such as dried beef, eggs and seasoned cheese (parmesan), ketogenic pasta (selected with a ketogenic ratio of 4:1), fruits with the lowest glycemic index (blueberry, raspberry), raw nuts and seeds, ghee butter, plant oils and fats from avocado, coconut and olives
Other: ketogenic diet
Subjects in this group will follow a low carbohydrate ketogenic diet

Active Comparator: Western diet
The western diet (WD) is composed mainly of whole cereals (spelt, rye, oat) and pseudo-cereals (buckwheat, quinoa, amaranth), whole grain pasta, potatoes, meet, fish, vegetables, fruit, legumes, olive oil, milk and red wine (at most 1 glass per day). It ensure a constant energy and macronutrient balance: protein 1.8g x Kg-1 x body weight-1 x day-1, (30%), fats 20-25% and carbohydrate 50-55%.
Other: Western diet
Subjects in this intervention will follow a normal western diet

Primary Outcome Measures :
  1. Fat body mass [ Time Frame: 4 weeks ]
    Body composition with DEXA: we measure body fat mass in grams.

  2. lean body mass [ Time Frame: 4 weeks ]
    Body composition with DEXA: we measure lean body mass in grams.

  3. Visceral Adipose tissue (VAT) [ Time Frame: 4 weeks ]
    Body composition with DEXA: VAT in grams

  4. Total body water [ Time Frame: 4 weeks ]
    We will use a BIA to calculate totally body water and intracellular and extracellular water in liters

Secondary Outcome Measures :
  1. resting energy expenditure (REE) [ Time Frame: 4 weeks ]
    Measured through gas analyzer in ml/02/kg min

  2. respiratory ratio (RR) [ Time Frame: 4 weeks ]
    Measured through gas analyses (ratio between CO2 and O2)

  3. specific performance [ Time Frame: 4 weeks ]
    Yoyo intermittent recovery test level 1: in seconds

  4. lower limb power [ Time Frame: 4 weeks ]
    squat jump test: height of the jump in cm

  5. quadriceps muscle area [ Time Frame: 4 weeks ]
    muscle area measured in cm2 through ultrasound

  6. quadriceps muscle thickness [ Time Frame: 4 weeks ]
    muscle thickness measured cm through ultrasound

  7. quadriceps strength [ Time Frame: 4 weeks ]
    isometric contraction measured in N, the normalized per muscle area (N x cm2)

  8. quadriceps strength per area [ Time Frame: 4 weeks ]
    the strength of isometric contraction (outcome 10) normalized per muscle area (Outcome 7). Expressed as (N x cm2)

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Layout table for eligibility information
Ages Eligible for Study:   18 Years to 30 Years   (Adult)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   Yes

Inclusion Criteria

  • semiprofessional soccer players
  • male

Exclusion Criteria:

  • body fat percentage over 32%, (determined via dual energy X-ray absorptiometry DEXA),
  • cardiovascular,
  • respiratory, gastrointestinal,
  • thyroid or any other metabolic diseases,
  • weight change more than 2 Kg over the last month,
  • adherence to special diets,
  • use of nutritional supplements (except a daily multivitamin-mineral)
  • use of medication to control blood lipids or glucose and goal-keepers.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT04078971

Layout table for location information
Nutrition and Exercise Lab, DSB, University of Padova
Padova, Italy, 35131
Sponsors and Collaborators
Antonio Paoli
Layout table for investigator information
Principal Investigator: Antonio Paoli, MD University of Padova

Layout table for additonal information
Responsible Party: Antonio Paoli, Professor, University of Padova Identifier: NCT04078971     History of Changes
Other Study ID Numbers: KDsoccer
First Posted: September 5, 2019    Key Record Dates
Last Update Posted: September 6, 2019
Last Verified: September 2019
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No
Plan Description: Raw data of outcomes on request

Layout table for additional information
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Antonio Paoli, University of Padova:
ketogenic diet
western diet
sport performance
muscle mass
body composition