Impact of a 6-week non-energy-restricted ketogenic diet on physical fitness, body composition and biochemical parameters in healthy adults.

Nutr Metab (Lond)

Department of Medicine I, Section of Clinical Nutrition and Dietetics, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Hugstetterstr 55, 79106 Freiburg, Germany.

Published: February 2017

AI Article Synopsis

Article Abstract

Background: The ketogenic diet (KD) is a very low-carbohydrate, high-fat and adequate-protein diet that without limiting calories induces different metabolic adaptations, eg, increased levels of circulating ketone bodies and a shift to lipid metabolism. Our objective was to assess the impact of a 6-week non-energy-restricted KD in healthy adults beyond cohorts of athletes on physical performance, body composition, and blood parameters.

Methods: Our single arm, before-and-after comparison study consisted of a 6-week KD with a previous preparation period including detailed instructions during classes and individual counselling by a dietitian. Compliance with the dietary regimen was monitored by measuring urinary ketones daily, and 7-day food records. All tests were performed after an overnight fast: cardiopulmonary exercise testing via cycle sprioergometry, blood samples, body composition, indirect calorimetry, handgrip strength, and questionnaires addressing complaints and physical sensations.

Results: Forty-two subjects aged 37 ± 12 years with a BMI of 23.9 ± 3.1 kg/m completed the study. Urinary ketosis was detectable on 97% of the days, revealing very good compliance with the KD. Mean energy intake during the study did not change from the habitual diet and 71.6, 20.9, and 7.7% of total energy intake were from fat, protein, and carbohydrates, respectively. Weight loss was -2.0 ± 1.9 kg ( < 0.001) with equal losses of fat-free and fat mass. VOpeak and peak power decreased from 2.55 ± 0.68 l/min to 2.49 ± 0.69 l/min by 2.4% ( = 0.023) and from 241 ± 57 W to 231 ± 57 W by 4.1% ( < 0.001), respectively, whereas, handgrip strength rose slightly from 40.1 ± 8.8 to 41.0 ± 9.1 kg by 2.5% ( = 0.047). The blood lipids TG and HDL-C remained unchanged, whereas total cholesterol and LDL-C increased significantly by 4.7 and 10.7%, respectively. Glucose, insulin, and IGF-1 dropped significantly by 3.0, 22.2 and 20.2%, respectively.

Conclusions: We detected a mildly negative impact from this 6-week non-energy-restricted KD on physical performance (endurance capacity, peak power and faster exhaustion). Our findings lead us to assume that a KD does not impact physical fitness in a clinically relevant manner that would impair activities of daily living and aerobic training. However, a KD may be a matter of concern in competitive athletes.

Trial Registration: DRKS00009605, registered 08 January 2016.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5319032PMC
http://dx.doi.org/10.1186/s12986-017-0175-5DOI Listing

Publication Analysis

Top Keywords

body composition
12
impact 6-week
8
6-week non-energy-restricted
8
ketogenic diet
8
healthy adults
8
energy intake
8
non-energy-restricted ketogenic
4
diet
4
diet physical
4
physical fitness
4

Similar Publications

[Body composition assessment methods in clinical practice].

Orv Hetil

January 2025

1 Semmelweis Egyetem, Általános Orvostudományi Kar, Belgyógyászati és Onkológiai Klinika Budapest, Korányi S. u. 2/A, 1083 Magyarország.

View Article and Find Full Text PDF

Menopause and obstructive sleep apnea: revealing an independent mediating role of visceral fat beyond body mass index.

BMC Endocr Disord

January 2025

Department of Respiratory and Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, 430060, China.

Background: Menopause is a significant phase in women's health, in which the incidence of obstructive sleep apnea (OSA) is significantly increased. Body fat distribution changes with age and hormone levels in postmenopausal women, but the extent to which changes in body fat distribution affect the occurrence of OSA is unclear.

Methods: This research performed a cross-sectional analysis utilizing data from the 2015-2016 National Health and Nutrition Examination Survey (NHANES).

View Article and Find Full Text PDF

Background: Metabolic and bariatric surgery (MBS) is a suitable solution for the treatment of morbid obesity. Investigating an MBS method that has the best outcomes has always been the main concern of physicians. The current study aimed to compare nutritional, anthropometric, and psychological complications of individuals undergoing various MBS Techniques.

View Article and Find Full Text PDF

This study aimed to investigate the role of myosteatosis, sarcopenia, and perioperative serum biomarkers as independent predictors of major complications within 180 days following radical cystectomy (RC) for muscle-invasive bladder cancer (MIBC). We retrospectively analyzed of 127 MIBC patients who underwent RC between 2013 and 2023 at a single institution. Preoperative body composition was assessed using CT scans at the L3 vertebral level to measure psoas muscle density (PMD), skeletal muscle density (SMD), axial muscle density (AMD), and muscle indices.

View Article and Find Full Text PDF

Objective: To analyze the relationship between body fat, motor skills, and physical fitness in children and adolescents.

Methods: 216 children and adolescents (143 males and 73 females, aged 5-15 years) from a social project composed this study. Body mass and height were measured to calculate the body mass index (BMI).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!