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.