Effects of Ketogenic Diet in Divers Breathing Enriched Air Nitrox

Not Applicable

Completed

• Conditions: Overweight and Obesity; Oxygen Toxicity; Exertion; Excess
• Interventions: Dietary Supplement: Ketogenic Diet

• Registration Number: NCT03114176
• Lead Sponsor: University of Padova

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 available

Study Timeline

• Study Start: 2016-05-25
• Primary Completion: 2016-07-10
• Study Completion: 2016-07-10
• Status Verified: 2017-04
• Study First Submitted: 2017-04-04
• Study First Submitted QC: 2017-04-10
• Last Update Submitted: 2017-04-10
• Study First Posted: 2017-04-14
• Last Update Posted: 2017-04-14

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Male
• Target Recruitment: 6

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.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Divers group	Ketogenic Diet	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 \[KETO-NTRX\]

Primary Outcome Measures

Name	Time	Method
Oxidative damage change	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	Change from Baseline Pro-inflammatory cytokines at twenty days	IL-1β (pg/ml), IL-6 (pg/ml) and TNF- α (pg/ml)

Secondary Outcome Measures

Name	Time	Method
Weight Loss	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)