Effects of gradual weight loss v. rapid weight loss on body composition and RMR: a systematic review and meta-analysis

Abstract

This systematic review and meta-analysis compared the effects of different rates of weight loss (WL), but equivalent total WL, on body composition and resting metabolic rate (RMR). Studies examining gradual vs. rapid WL on body composition and RMR in participants with overweight/obesity published up to October 2019 were identified through PubMed, the Cochrane Library, Web of Science, Embase, SCOPUS, and Ovid databases. Meta-analysis was carried out using a fixed or random-effects model as appropriate. Although the magnitude of WL was similar (mean difference: 0.03 kg, 95% CI [-0.65, 0.71]), gradual WL promoted greater reductions in fat mass (FM) (-1 kg, 95% CI [-1.70, -0.29]) and body fat percentage (BFP) (-0.83%, 95% CI [-1.49, -0.17]). Gradual WL significantly preserved RMR compared with rapid WL (97.39 kcal, 95% CI [76.76, 118.01]). However, there was no significant difference in waist and hip circumferences, waist-to-hip ratio (WHR), and fat-free mass (FFM) between gradual and rapid WL. The present systematic review and meta-analysis indicates beneficial effects of gradual WL, as compared to rapid WL, on FM, BFP, and RMR in individuals with overweight/obesity. However, FFM changes and anthropometric indices did not significantly differ following different rates of WL.

Case Study: Body Composition Changes Resulting from a Nutritional Intervention on a Professional Vegan Powerlifter

“…Nonetheless, it was also recently reported that a gradual weight loss is associated with greater loss in FM and body fat percentage, but it was not associated with changes in FFM in overweight and obese adults and older individuals [17]. Our results show that the athlete's mean weekly weight loss during the first four weeks of the intervention (0.47 kg/week) was consistent with results reported by some authors [9], while others recommended minor weekly weight losses in physique athletes (<0.5% of BM per week) [18]. It should be mentioned that these nutritional recommendations were obtained for bodybuilders, whose body fat percentage tends to be lower during the season.…”

Intermittent fasting and continuous energy restriction result in similar changes in body composition and muscle strength when combined with a 12 week resistance training program

“…Additionally, differences in total amounts (and therefore overall rate) of weight loss between sexes could partially explain the greater LBM gains in females compared to males. Previous research has shown that slower rates of weight loss may be beneficial for LBM preservation, though this finding is not ubiquitous in the literature [ 53 ]. Congruent with this, when all weight loss and LBM changes for both sexes were pooled together in the current study, there was a moderate, positive correlation between change in weight and change in LBM ( r = 0.63).…”

Predicting Adaptations to Resistance Training Plus Overfeeding Using Bayesian Regression: A Preliminary Investigation

“…Furthermore, the effects of overfeeding in both RT-naïve and resistance-trained populations in conjunction with longer duration RT interventions could allow for a better understanding of adaptations to these interventions. Longer interventions could also allow for the implementation of slower rates of BM gain, which could potentially benefit body composition outcomes [ 56 ]. Importantly, it remains unknown the exact amount of energy required for skeletal muscle hypertrophy, whether this cost must be met through endogenous and/or exogenous means, and which physiological factors influence this energy need [ 50 ].…”