Sarcopenia is an important recently defined disease affecting people aged ≥65 years all over the world. Improving the assessment of loss of muscle mass is becoming mandatory. In this regard, various new technologies have been advanced. Although the gold standard is represented by magnetic resonance imaging (MRI) or magnetic resonance spectroscopy (MRS), computed tomography (CT) or dual-energy X-ray absorptiometry (DXA), followed by biological impedance analysis (BIA) compared with DXA, there are numerous correlations between sarcopenia and health domain of everyday life that must be investigated and addressed, trying to obtain the best possible outcome in the older population. In this review, we focused on all types of new technologies assessing loss of muscle mass, frailty, independence, walking, capacity to get dressed, and loss of balance or sleepiness in older people and that could improve the diagnosis of sarcopenia or the rehabilitation of sarcopenic patients to prevent possible accidents. Different technologies have been proposed to investigate the factors promoting the loss of muscle mass and weakness. Despite the standard EWGSOP 2019 guidelines defining a specific methodology for the diagnosis of sarcopenia, not all domains and devices were included, and new frontiers of prevention have been explored.