PURPOSE In an attempt to combine muscle atrophy and muscle hypertrophy in a single animal model, our group has experimented with a suturing technique to retain the unloaded gastrocnemius muscle during functional overload of the soleus and plantaris muscles. METHODS As part of a larger research study, CHF-148 and H4 hamsters were randomly assigned to either an overload/unload (OU) or control (C) group. Animals in the OU group underwent bilateral bisection of the gastrocnemius contribution to the triceps surae tendon. The proximal portion of the tendon was drawn superiorly and sutured deep into the medial head of the gastrocnemius muscle to prevent reattachment. Six weeks following surgery, the soleus (S), plantaris (P), medial gastrocnemius (MG) and lateral gastrocnemius (LG) were removed and analyzed for fiber cross-sectional area (CSA). Immunohistochemistry was used to analyze myosin heavy chain (MHC) isoform content. RESULTS Based on preliminary results, fiber CSA tended to be greater in overloaded soleus (OU-S: 2455 ± 957 vs. C-S: 2256 ± 625) and plantaris muscles (OU-P: 2459 ± 1147 vs. C-P: 1950 ± 798). Surprisingly, there was also a tendency for fiber CSA to be greater in the surgically ablated gastrocnemius muscle (OU-MG: 3100 ± 1347 vs. C-MG: 2131 ± 916; OU-LG: 2848 ± 1203 vs. C-LG: 2426 ± 983). While muscle unloading is normally associated with a decrease in slow myosin (MHCI) isoform expression, no obvious decrease in the number of fibers expressing MHCI exclusively was observed for OU-MG when compared to C-MG. Conversely, some of the OU-LG muscles contained a high proportion of fibers expressing the MHCI isoform, whereas no C-LG muscles contained any fibers expressing the MHCI protein. CONCLUSIONS Although direct reattachment of the gastrocnemius to the triceps surae tendon did not occur, portions of this muscle were still able to contribute to force generation in the OU animals. The variability within the OU group precludes the use of this technique as a reliable means of combining muscle unloading with muscle overloading. Refinement of the technique may provide better results in future experiments.