Are sit-to-stand and isometric handgrip tests comparable assessment tools to identify dynapenia in sarcopenic people?

Sarcopenia is a neuromuscular disease characterized by the simultaneous existence of reduced muscle strength and muscle atrophy. The current recommendations for the diagnosis of sarcopenia suggest dynapenia be operationalized using either isometric handgrip strength (IHG) or sit-to-stand (STS) tests. However, specific associations between each of these assessment tools and sarcopenia-related parameters have been observed. In addition, important neuromuscular and biomechanical aspects differ between IHG and STS. This scenario has important clinical implications and calls for detailed studies to refine the current recommendations for sarcopenia identification. The present communication presents evidence to foster a constructive debate on the matter.