Clinical Trials Logo

Clinical Trial Summary

One of the major challenges for treating obesity is to maintain a weight reduced state on the long term due to the high rate of weight regain. Therefore, the aim of this study is to evaluate the effects of an intermittent versus a continuous energy restriction in body composition (body weight, fat mass and fat-free mass) and metabolic adaptation, in women with obesity.

Clinical Trial Description

Literature is full of lifestyle interventions aimed for weight loss (WL) in several populations. However, one of the major challenges for treating obesity is WL maintenance on the long term due to the high rate of weight regain. The reduction of the resting metabolic rate (RMR) is one of the identified aspects regarding compensatory metabolic alterations. After a WL intervention, decreases in RMR are mainly explained by the loss of fat-mass (FM) and fat-free mass (FFM). However, some authors showed that these reductions tend to be higher than predicted (explained by FM and FFM loss), a phenomenon called "metabolic adaptation" (MA). MA has been studied as a possible barrier to WL, WL maintenance and may contribute to weight regain. However, its relevance on long-term WM has been recently questioned. It is known that in order to lose weight, a negative energy balance (EB) must be achieved, meaning when EE surpasses the energy intake (EI). However, this negative EB may be achieved through several strategies, by changing the EI (energy restriction (ER)) and/or EE (increasing physical activity). Regarding EI strategies, continuous energy restriction (CER) is the most common nutritional strategy for WL, consisting in a daily energy restriction according to one's specific needs. However, some concern has been pointed out regarding this widely used strategy, once it evolves several behavioural, metabolic and endocrine responses that may contribute to therapeutic adherence, undermining WL and its maintenance. On the other hand, intermittent energy restriction (IER) has been recently suggested as an alternative to CER. IER consists in interspersing periods of ER with periods of neutral EB, called "refeed" or "diet breaks" during the WL phase. Energy restriction is followed by several adaptive responses, namely endocrine, including thyroid, appetite regulation and steroid hormones, influencing the energy expenditure (EE), body composition and satiety. Therefore, understanding how hormones may influence RMR and as a consequence, AT, it´s crucial to a better understanding. According to the literature, compensatory metabolic responses following ER and WL can be reversed following a 7-to-14-day period of energy balance post-weight loss. Therefore, considering that the length of the nutritional intervention for WL may benefit a reduction, we consider relevant to study other ER designs/patterns, namely 2 weeks in ER interspersed with 1 week in EB, comparing to a CER. Taking into account this therapeutic as a potential opportunity for the obesity's treatment, this paper describes the protocol for a randomized controlled trial (RCT), which targets to evaluate the effects of an IER (alternating 2 weeks of ER with 1 in neutral EB), comparing to a CER. This trial aims: a) to compare the effects of a IER vs CER strategy on body composition variables (body weight, fat mass and fat-free mass) and in metabolic adaptation and, b) to understand if participants will be able to maintain a reduced weight state after 12 months (successful weight-loss maintenance), in both groups. ;

Study Design

Related Conditions & MeSH terms

NCT number NCT05184361
Study type Interventional
Source Universidade do Porto
Contact Filipa M Cortez, PhDc
Phone 00351936587812
Email [email protected]
Status Not yet recruiting
Phase N/A
Start date January 2022
Completion date January 2024

See also
  Status Clinical Trial Phase
Recruiting NCT04101669 - EndoBarrier System Pivotal Trial(Rev B) N/A
Recruiting NCT04243317 - Feasibility of a Sleep Improvement Intervention for Weight Loss and Its Maintenance in Sleep Impaired Obese Adults N/A
Terminated NCT03772886 - Reducing Cesarean Delivery Rate in Obese Patients Using the Peanut Ball N/A
Completed NCT03640442 - Modified Ramped Position for Intubation of Obese Females. N/A
Completed NCT04506996 - Monday-Focused Tailored Rapid Interactive Mobile Messaging for Weight Management 2 N/A
Recruiting NCT04575194 - Study of the Cardiometabolic Effects of Obesity Pharmacotherapy Phase 4
Active, not recruiting NCT04513769 - Nutritious Eating With Soul at Rare Variety Cafe N/A
Withdrawn NCT03042897 - Exercise and Diet Intervention in Promoting Weight Loss in Obese Patients With Stage I Endometrial Cancer N/A
Completed NCT03644524 - Heat Therapy and Cardiometabolic Health in Obese Women N/A
Recruiting NCT04353258 - Research Intervention to Support Healthy Eating and Exercise N/A
Completed NCT04507867 - Effect of a NSS to Reduce Complications in Patients With Covid-19 and Comorbidities in Stage III N/A
Recruiting NCT03227575 - Effects of Brisk Walking and Regular Intensity Exercise Interventions on Glycemic Control N/A
Completed NCT01870947 - Assisted Exercise in Obese Endometrial Cancer Patients N/A
Recruiting NCT05040971 - Research Study Looking at How Well Semaglutide Works in People Living With Obesity and Prediabetes Phase 3
Suspended NCT03652987 - Endocrine and Menstrual Disturbances in Women With Polycystic Ovary Syndrome (PCOS)
Completed NCT03714646 - Beta Glucan and Acetate Production N/A
Completed NCT04971317 - The Influence of Simple, Low-Cost Chemistry Intervention Videos: A Randomized Trial of Children's Preferences for Sugar-Sweetened Beverages N/A
Active, not recruiting NCT04353726 - Knowledge-based Dietary Weight Management. N/A
Enrolling by invitation NCT03063606 - Behavioral and Pharmacologic Treatment of Binge Eating and Obesity: Specialist Treatment Phase 2/Phase 3
Completed NCT03317587 - Inspiring Nutritious Selections and Positive Intentions Regarding Eating and Exercise (INSPIRE) N/A