< I o I 1 I I 234 I 5 twitch frequency (Hz) FIGURE 3. Cytosolic ATP / ADP concentration ratio at steadystate in forearm flexor muscle as a function of stimulation frequency (in Hz).
Nielsen like techniques for analysis of the complete metabolome, and here novel technologies are currently being developed that allow an efficient screening of the (low molecular weight) metabolome. Even though recent developments show that it is possible to screen for up to 300 metabolites or more in a single experiment [16,31]' the different structure and different chemical properties of the many intracellular metabolites require different analytical techniques. However, metabolite profiling will allow exact quantification of a metabolic state.