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Effects of Ketogenic Diet on Triathlon's Performance

Effects of Five Weeks of Ketogenic Diet on Long Distance Triathletes Performance

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03691558
Enrollment
16
Registered
2018-10-01
Start date
2017-02-01
Completion date
2017-07-12
Last updated
2018-10-02

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Ketogenic Dieting, Physical Activity

Keywords

ketogenic diet, triathlon, VO2max, PPO

Brief summary

The study aimed to verify the effects of 5 weeks of ketogenic diet (KD) on some performance index in long distance triathletes

Detailed description

16 well trained male long distance Triathletes participates in the study (30.65 ± 10.77 years of age), with minimum one year of triathlon competition experience and 8-10 hours of training per week. All subjects had a personal interview made by a registered Medical Doctor about the diet intervention prior to the beginning of the study. Moreover participants were educated about the benefits and limitations of the two different dietary treatments and asked to nominate their preference for, or non-acceptance of, each of these interventions. Thus participants also decided liberally if participate for the diet intervention or not. This choice was decided to prevent any type of dropout in the KD group, considering that a free and conscious choices is better for the adherence on a strict diet like ketogenic diet . Investigators were thus able to allocate the athletes to their preferred treatment, while achieving suitable matching of groups based on age, body mass and aerobic power. All the participants were healthy and injured free, and not consuming a low carbs diet prior to the study. The diet macronutrient percentage distribution was the following: for ND the percentages were 25% of TDC (total daily calories), fat were 20% of TDC and carbohydrates represented the 55% of TDC; for KD the percentages were 68% fat, 26% protein and 6% carbohydrate. In the KD very low carbohydrate foods that simulate carbohydrates taste food like croissants, bread and cracked slices made by Le Gamberi Foods (Forlì, Italy), were used for a better compliance to the dietary intervention. Subjects undertaken an anthropometric test and two different cardiopulmonary tests with a professional cycloergometer (MARCA). The anthropometric measures were taken to evaluated body weight. height and body composition . After the body composition analysis subjects underwent to a maximal cardiopulmonary test (GXT) to evaluate the maximal oxygen consumption (VO2max). The following day subjects performed 60 minutes at 45% of PPO to assess endurance performance at ironman biking race-pace. The day after test session KD group started the KD 5 weeks. The Control Group (S) followed his habitual normo-caloric, balanced diet. The same order and procedures were conducted for testing the subjects post diet intervention. Anthropometric and performance test was conducted in the same order for each subjects and at the same time of the day. Blood ketones were measured each other day to ensure the compliance to KD

Interventions

OTHERKetogenic diet

total daily caloric intake was divided into 5 meals. Individual daily caloric need is calculated referring to body composition and adjusted for daily activity (Frankenfield, Roth-Yousey, & Compher, 2005; Wang et al., 2000). Macronutrients percentage is 68% fat, 26% protein and 6% carbohydrate Paoli et al. 2013). Very low carbohydrate foods that simulate carbohydrates taste food like croissants, bread and cracked slices made by Le Gamberi Foods (Forlì, Italy), are used for a better compliance to the dietary intervention

total daily caloric intake was divided into 5 meals. Individual daily caloric need is calculated referring to body composition and adjusted for daily activity (Frankenfield, Roth-Yousey, & Compher, 2005; Wang et al., 2000). The diet macronutrient percentage distribution is the following: protein is 25% of TDC (total daily calories), fat is 20% of TDC and carbohydrates represented the 55% of TDC

Sponsors

Universidade Federal de Goias
CollaboratorOTHER
University of Palermo
CollaboratorOTHER
University of Padova
Lead SponsorOTHER

Study design

Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
SINGLE (Outcomes Assessor)

Masking description

Treatment and control were masked with A and B

Intervention model description

It is single blind, parallel arms study

Eligibility

Sex/Gender
MALE
Age
20 Years to 40 Years
Healthy volunteers
Yes

Inclusion criteria

* long distance Triathletes (8-10 hours of training per week), competing in half Ironman or Ironman * no previous experience of low carbohydrate diet * more than 3 years of training

Exclusion criteria

* recent (less than 6 months) musculoskeletal injuries * more than 2 months without training in the last 2 years

Design outcomes

Primary

MeasureTime frameDescription
VO2 at 45% of peak power outputafter 5 weeksWe measured the mean VO2 during one hour at the 45% of peak power output (PPO) measured during the first test

Secondary

MeasureTime frameDescription
VO2 per Kg/bwafter 5 weeksVO2 measured as ml O2 per kilograms of body weight
VO2maxafter 5 weeksMaximal oxygen consumption measured through a incremental bike test
Body composition LBMafter 5 weeksLean body mass (Kg) measured by Body Impedence Analysis
Body composition FMafter 5 weeksFat mass (Kg) measured by Body Impedence Analysis
Body Weightafter 5 weeksin Kg

Countries

Italy

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026