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Effects of Ketogenic Diet in Divers Breathing Enriched Air Nitrox

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: NCT03114176
Recruitment Status : Completed
First Posted : April 14, 2017
Last Update Posted : April 14, 2017
Information provided by (Responsible Party):
Antonio Paoli, University of Padova

Tracking Information
First Submitted Date  ICMJE April 4, 2017
First Posted Date  ICMJE April 14, 2017
Last Update Posted Date April 14, 2017
Actual Study Start Date  ICMJE May 25, 2016
Actual Primary Completion Date July 10, 2016   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: April 10, 2017)
  • Oxidative damage change [ Time Frame: Change from Baseline Oxidative damage at twenty days ]
    8-OH-dG (ng ⋅ mg-1 creatinine) and 8-iso-PGF2α (ng ⋅ mg-1 creatinine)
  • Pro-inflammatory cytokines change [ Time Frame: Change from Baseline Pro-inflammatory cytokines at twenty days ]
    IL-1β (pg/ml), IL-6 (pg/ml) and TNF- α (pg/ml)
Original Primary Outcome Measures  ICMJE Same as current
Change History No Changes Posted
Current Secondary Outcome Measures  ICMJE
 (submitted: April 10, 2017)
Weight Loss [ Time Frame: Weight was registered before (T0) and after twenty days of no diving activity in which subjects were engaged in a 7-days Ketogenic Diet (T3). ]
Kilogram (Kg)
Original Secondary Outcome Measures  ICMJE Same as current
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
Descriptive Information
Brief Title  ICMJE Effects of Ketogenic Diet in Divers Breathing Enriched Air Nitrox
Official Title  ICMJE Effects of Exercise and Dietary Inatke on Muscle Metabolism and Inflammatory Status Modulated by Oxygen Free Radicals and Cytokines in Humans
Brief Summary

Overweight divers face a challenging activity such as immersions, starting from a higher levels of circulating cytokines and oxidative stress. Ketogenic Diet (KD) is described as effective in weight loss, in countering inflammation and oxidative stress, and used in the control of drug-refractory seizures.

The aim of our pilot study was to evaluate if a ketosis state induced by a specific dietary regime, may have a protective effect on oxidative stress damages and inflammatory status, that accompanies both overweight and diving activities.

Blood and urine samples from six overweight divers were obtained a) before (CTRL) and after a dive breathing Enriched Air Nitrox and performing light underwater exercise (NTRX), b) after a dive (same conditions) performed after 7 days of KD (K-NTRX). We measured urinary 8-isoprostane and 8-OH-2-deoxyguanosine evaluating lipids peroxidation and DNA oxidative damages. Plasmatic IL-1beta, IL-6 and TNF-alpha levels were measured to investigate the inflammatory status.

Detailed Description Not Provided
Study Type  ICMJE Interventional
Study Phase  ICMJE Not Applicable
Study Design  ICMJE Allocation: N/A
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Prevention
Condition  ICMJE
  • Overweight and Obesity
  • Exertion; Excess
  • Oxygen Toxicity
Intervention  ICMJE Dietary Supplement: Ketogenic Diet
Diet consisted of a very low carbohydrate ketogenic diet (for 7 days) with the use of some phytoextracts as previously described. The consumed diet was primarily made of beef and veal, poultry, fish, raw and cooked green vegetables without restrictions, cold cuts (dried beef, carpaccio and cured ham), eggs and seasoned cheese (e.g., parmesan). The allowed drinks were infused tea, moka coffee and herbal extracts. The foods and drinks that subjects had to avoid included alcohol, bread, pasta, rice, milk, yogurt, soluble tea, and barley coffee. To facilitate adherence to the nutritional regime, a variety of special meals based on protein and fibers were given to each subject. KD characteristics are protein intake 1.3g/kg/day, to maintain skeletal muscle mass; carbohydrates intake less than 40 g/day and 50-60% of total kcal to induce ketosis. In accordance with a hypocaloric profile, total energy intake was calculated with 200 kcal more than basal metabolic rate.
Study Arms  ICMJE Experimental: Divers group
Throughout each dive, subjects performed a 20-minute long mild exercise on an underwater bike. The depth of dive was set at 15 meters, where the subjects performed an activity guided by Borg CR-10 scale at intensity level 3 (25 rpm). The ascent rate was set at 10 m/min, with a decompression stop at 5 meters for 3 min, according to the US Navy Manual Diving Table. 48 h prior to the immersions, none of the participants consumed medications or dived or flew. In the first part of the experiment, all subjects performed a dive breathing Enriched Air Nitrox (EAN, 32% ppO2). Baseline clinical measurements were collected before and after this first dive in order to have a reference [CTRL] and to measure physiological modifications due to immersion [NTRX]. After twenty days of no diving activity, subjects were engaged in a KD for seven days. At the end of this period, subjects performed a single immersion breathing EAN. The measures were performed after this single dive [KETO-NTRX]
Intervention: Dietary Supplement: Ketogenic Diet
Publications * Not Provided

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Recruitment Information
Recruitment Status  ICMJE Completed
Actual Enrollment  ICMJE
 (submitted: April 10, 2017)
Original Actual Enrollment  ICMJE Same as current
Actual Study Completion Date  ICMJE July 10, 2016
Actual Primary Completion Date July 10, 2016   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

Inclusion Criteria:

  • to be in an overweight state (BMI ≥ 25 kg/m2) and no history of orthopedic, cardiovascular, renal or metabolic disorders.

Exclusion Criteria:

  • not to be in an overweight state (BMI ≥ 25 kg/m2) and a history of orthopedic, cardiovascular, renal or metabolic disorders.
Sex/Gender  ICMJE
Sexes Eligible for Study: Male
Ages  ICMJE 25 Years to 65 Years   (Adult, Older Adult)
Accepts Healthy Volunteers  ICMJE Yes
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE Not Provided
Removed Location Countries  
Administrative Information
NCT Number  ICMJE NCT03114176
Other Study ID Numbers  ICMJE NEPL-DSB 06/16
Has Data Monitoring Committee Not Provided
U.S. FDA-regulated Product
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Product Manufactured in and Exported from the U.S.: No
IPD Sharing Statement  ICMJE
Plan to Share IPD: No
Responsible Party Antonio Paoli, University of Padova
Study Sponsor  ICMJE University of Padova
Collaborators  ICMJE Not Provided
Investigators  ICMJE
Study Director: Bosco Gerardo, MD, PhD University of Padova
PRS Account University of Padova
Verification Date April 2017

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP