Improved non-invasive muscle typology assessment for individualized exercise prescription

There are considerable differences among individuals in the magnitude of improvement in cardiorespiratory fitness in response to a standardized exercise program. Understanding why there is human variability in the adaptations to training is of particular importance for personalized exercise medicine applications and also for elite athletes motivated by the pursuit of sports performance. The large inter-individual differences in muscle typology may explain, in part, the divergent responses to exercise training. Slow twitch fibers have low fatigability and may adapt optimally to high-volume contractions, whereas fast twitch fibers have high fatigability and need longer to recover but may adapt optimally to high-frequency contractions. Therefore, the current project will compare individual responses in participants with fast-twitch and slow-twitch typology following both a one-fits-all training period and an individualized training period, in which modalities are adapted to muscle typology. Interaction between muscle typology, training modalities and training effects are rarely investigated because the only available method to quantify muscle fiber type composition was histological evaluation of an invasive muscle biopsy. Yet, we have developed a non-invasive method by proton magnetic resonance spectroscopy, which we want to improve in this project. This will allow us to develop guidelines for adequate training programs in a personalized and therefore more cost-effective manner.