Preservation of fat-free mass after two distinct weight loss diets with and without progressive resistance exercise

Metab Syndr Relat Disord. 2012 Jun;10(3):167-74. doi: 10.1089/met.2011.0104. Epub 2012 Jan 27.


Background: Preserving fat-free mass (FFM) during weight loss is important in older adults. The purpose was to examine a low-fat diet (LFD) versus a carbohydrate-restricted diet (CRD) with and without progressive resistance exercise (PRE) on preservation of FFM in older men with metabolic syndrome.

Methods: A total of 42 men (59±7 years) were matched [body mass index (BMI)] and randomized to LFD, LFD&PRE, CRD, and CRD&PRE. PRE groups performed supervised strength training three times per week. Body weight, composition, metabolic syndrome criteria, and strength were measured at baseline and week 12. A 3-day diet record was kept at baseline and at weeks 1, 6, and 12.

Results: Attrition (24%) was similar between groups. Depicted as % carbohydrate:fat:protein, the intervention diet was: LFD=55:24:18, LFD&PRE=57:20:20, CRD=16:54:28, and CRD&PRE=12:56:31. Weight (lb) decreased similarly in all groups (LFD, -18.0±7.4; LFD&PRE, -19.8±12.8; CRD, -20.2±8.0; CRD&PRE, -22.7±6.0; P<0.001), and number of participants with metabolic syndrome decreased in all groups (-3, -6, -3, -4, respectively). Percent of weight loss from appendicular FFM was 27.5%, 15.9%, 15.7%, and 17.3% respectively. A trend was found when comparing LFD and LFD&PRE (P=0.068), and when comparing LFD&CRD (P=0.072). Triglycerides improved more for the LFD&PRE, CRD, and CRD&PRE groups compared to the LFD group (P<0.05). Improvements in high-density lipoprotein-cholesterol were better in the CRD&PRE group (4.1±5.1 mg/dL) versus the LFD group (-5.0±5.9 mg/dL; P<0.01).

Conclusions: LFD&PRE, CRD, and CRD&PRE preserve FFM similarly. PRE is an important component of a LFD during weight loss in this population.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adiposity
  • Aged
  • Biomarkers / blood
  • Blood Pressure
  • Body Composition*
  • Body Mass Index
  • Combined Modality Therapy
  • Diet, Carbohydrate-Restricted*
  • Diet, Fat-Restricted*
  • Factor Analysis, Statistical
  • Humans
  • Male
  • Massachusetts
  • Metabolic Syndrome / diagnosis
  • Metabolic Syndrome / diet therapy
  • Metabolic Syndrome / physiopathology
  • Metabolic Syndrome / therapy*
  • Middle Aged
  • Muscle Strength
  • Overweight / diagnosis
  • Overweight / diet therapy
  • Overweight / physiopathology
  • Overweight / therapy*
  • Resistance Training*
  • Time Factors
  • Treatment Outcome
  • Waist Circumference
  • Weight Loss*


  • Biomarkers