Muscle fatigue and muscle weakness: what we know and what we wish we did

The purpose of this Research Topic is to discuss evidence coming from macroscopic observations on the whole human/animal to investigations at the molecular level in an effort to identify critical factors in muscle fatigue and muscle weakness, in health and disease.

Why is this important?

Skeletal muscles confer movement to the human body using vast amounts of energy provided through complex metabolic pathways. Thus, whole body mobility and energy balance are dictated by muscle contraction. On the other side, muscle function reflects overall health status, as chronic conditions and/or ageing affect either or both of muscle quality (protein and fat content) and quantity (mass). In health, muscle fatigue is temporary and recovery occurs rapidly. In ageing or chronic disease however, muscle fatigue may occur prematurely and be persistent, endangering thus a person’s safety (i.e. weakness leads to falls), and leading the sufferer in a self-perpetuating vicious cycle of inactivity -> disuse muscle atrophy/metabolic disturbance and so on, that compounds morbidity (i.e. causing metabolic syndrome, fatness, hypertension, muscle cachexia) and that eventually leads to premature death.

Research in skeletal muscle physiology and biophysics is at an exciting phase. The advent of new methodologies and technological advancements have allowed researchers to advance our knowledge on the “how’s” and “why’s” of muscle contraction – however there are still many unanswered questions especially when disease states are implicated.

Such questions need addressing if as a scientific community we aspire to secure better designed interventions to improve muscle function, and thus improve quality of life and life prognosis for the ageing population and chronic disease patients.