In myofibrils, during exercise (contraction) ADP levels are very high, which favors resynthesis of ATP. Technos acxel, launched in 1987, utilized the additive analysis/resynthesis model, in an FFT implementation. Sound hybridisation or "morphing" has been implemented by additive resynthesis. By modifying the sum of sinusoids representation, timbral alterations can be made prior to resynthesis. The energy released is coupled to the energy requirement necessary for the resynthesis of ATP. Software that implements additive analysis/resynthesis includes&colon; SPEAR, LEMUR, LORIS, SMSTools, ARSS. A resynthesis pathway reconstructs an audio signal from a group of segments. MBROLA software uses MBROLA (Multi-Band Resynthesis OverLap Add) algorithm for speech generation. It is generally used for speech analysis and resynthesis.