Individual Response to Standardized Exercise: Total and Abdominal Adipose Tissue.

PURPOSE (1) Determine the effect of exercise amount and intensity on the proportion of adipose tissue (AT) responses likely, very likely, and unlikely above the minimal clinically important difference (MCID); and (2) Examine whether clinically meaningful anthropometric changes reflect individual AT responses above the MCID. METHODS Men (n=41) and women (n=62) (52.7 ± 7.6 years) were randomized to control (N=20); low amount low intensity (LALI, N=24); high amount low intensity (HALI, N=30); and high amount high intensity (HAHI, N=29) exercise for 24 weeks. AT changes were measured by MRI. The probability that individual responses were > MCID after adjusting for technical error of measurement were calculated for each individual and categorized as: 'Unlikely' = < 25%, 'Possibly' = 25-74%, 'Likely' = 75-94%, 'Very Likely' = 95-100% chance. RESULTS The HALI (total AT) and HAHI (total AT, visceral AT) groups had a greater proportion of individuals whose response was "very likely" ≥ MCID vs controls (p<0.006). Across the abdominal AT depots, for individuals who reduced WC or body weight ≥ 2 cm or 2 kg, respectively, 51-69% of responses were "likely" or "very likely" beyond the MCID. CONCLUSION Increasing exercise amount and/or intensity may increase the proportion of individuals deemed 'very likely' to achieve clinically meaningful AT reductions. The use of anthropometric change to identify individual response for adiposity reduction remains a challenge.