The exact cellular and molecular mechanisms involved in the adaptation of skeletal muscle following exercise yet to be fully understood. Increased understanding of the effects of exercise on skeletal muscle phenotype has important implications in the fields of sporting performance and also musculoskeletal pathologies. Key signalling pathways activated following specific forms of exercise have been identified; including ‘AMPK-PGC-1α’ and ‘PKB-TSC2-mTOR’. In vivo exercise testing poses problems with regards to experimental control; accounting for inter-individual differences and methods relating to tissue sampling are common flaws of such research. The necessity to develop a model of skeletal muscle in vitro which relates to exercise has prompted the development of a new field within exercise physiology. The current investigation aims to identify key genes and proteins that are up-regulated following divergent regimes of mechanical stimulation of a 3D in vitro muscle model. An established protocol was used for this experiment (1). Briefly, C2C12 mouse muscle cells were seeded in neutralised type-1 rat tail collagen and plated into custom made 3D wells. In order to find an optimum seeding density of cells for future experiments, gels were cast at 1, 2, 3 and 4 million cells/ml. Each chamber held a custom built floatation bar (“A-frame”) at either end. The “A-frames” provided two attachment points within the culture withteh collagen gel suspended in between, allowing the development of longitudinal lines of principle isometric strain. This tension provided sufficient mechanical stimulus to promote the cells to align and fuse in a single plane. The result was a 3D tissue possessing uniaxially aligned and differentiated myotubes, capable of performing directed contraction. The model was then tethered to a culture force monitor (2), which allows real time analysis of force generation within the construct. Use of a CFM equipped with a stepper motor known as the tensioning culture force monitor (t-CFM) allows programmable regimes of mechanical strain to be applied to the construct. Regimes which aim to replicate stimulation associated with endurance training or resistance training are being currently investigated. The effects of these regimes are analysed by immunohistochemistry and RT-PCR. Immunohistochemical analysis has confirmed the formation of primary myotubes. Preliminary RT-PCR and CFM data suggests that the myotubes present in these 3D cultures are representative of in vivo muscle development and regeneration. The components of the 3D in vitro muscle model are in place to investigate the specific cellular and molecular adaptations of skeletal muscle following exercise related physiological cues.