Body Recomp: Maintenance or Deficit?

Body recomposition changes are similar among individuals following an isocaloric diet vs. a slight calorie deficit during 10 weeks of resistance training when protein intake is matched. 

Overview

• What did they test? In this study, researchers compared the effect of following an isocaloric diet (ISO) vs. a slight daily calorie deficit (DEF) on body composition changes in individuals undergoing a 10-week resistance training program. Participants in the DEF group followed a 250-calorie daily deficit, while the ISO group consumed maintenance calories. Protein was matched at 2.5 g/kg per day in both groups and the outcomes were compared to a control group that maintained their habitual diet. 
• What did they find?  Both the ISO and DEF groups showed significant increases in fat-free mass over the 10-week intervention.  Participants in the DEF group also had a significant reduction in fat mass from the beginning to the end of the intervention, while the ISO group saw a trend towards a reduction in fat mass that did not reach significance. 
• What does it mean for you? Participants in this study were able to achieve body recomposition while following both an isocaloric diet and a slight calorie deficit. These findings suggest that both of these approaches can be effective for body recomposition if protein intake is adequate and you’re consistently engaging in resistance training. 

What’s the Problem?

The majority of research on changing body composition has focused on either fat loss or muscle gain, but in practice many people seek to achieve both simultaneously, which is referred to as body recomposition. It was previously thought that body recomposition was only possible in obese individuals or those with no resistance training experience, but recent research has shown that body recomposition is possible even among individuals with a history of resistance training 1.

To date there is limited research on comparing the effectiveness of various body recomposition approaches in resistance-trained participants and more research is needed to determine to what degree body recomposition is possible and what approaches are most effective for optimizing muscle gain and fat loss simultaneously. 

Purpose

The purpose of this study was to compare the effects of following an isocaloric diet (ISO) compared to a slight 250 calorie daily deficit (DEF) on body composition changes while following a 10-week resistance training program and consuming a high protein diet. 

Hypothesis

The authors hypothesized that both diets would lead to body recomposition compared to the control condition and that there may be differences between the ISO and DEF groups.