This surprises me. I am sure we can all think of a time where our weight stayed the same but you lost a noticeable amount of fat. What do you think replaced the fat you lost to keep your weight the same? It is fact in that it is possible. It isn't necessarily to any significant degree but it is possible. --- Circuit training in resistance trained men; Invalid Link Removed "Significant decreases were found in % body fat in the HRC group only; HRC and TS training both resulted in an increased lean but not bone mass. The HRC training was as effective as TS for improving weight lifting 1RM and peak power, shuttle-run performance and lean mass. Thus, HRC training promoted a similar strength-mass adaptation as traditional training while using a shorter training session duration." --- In overweight women; Invalid Link Removed "Hydrostatic data revealed that each group lost an identical amount of fat (5.0 lb), but the high-intensity group gained more than twice as much fat-free mass (4.3 vs 1.8 lb). The greater increase in fat-free mass by the high-intensity group explains why the low-intensity group had a greater absolute weight loss." --- Concurrent training in older women; Invalid Link Removed "All groups increased fat free mass, strength and aerobic fitness and decreased fat mass" ---- Sedentary, overweight adults; Invalid Link Removed "After training, both female exercise groups showed equivalent or greater relative improvements in strength and aerobic fitness than did the male exercise groups (p < 0.05); however, the male exercise groups increased TB-FFM and reduced TB-FM more than did the female exercise groups (p < 0.05)." --- Concurrent exercise in female college athletes; Invalid Link Removed "Integrated CE produced discernible increases in lower- (23.3%) and upper- (17.8%) body muscle strength, lower-body muscle endurance (27.8%), FFM (3.3%), and lower-body flexibility (8.4%) and a decline in fat mass (-4.5%) and percent body fat (-5.7%)" --- etc etc etc