Background <p>It is important to evaluate the physical fitness and sarcopenia levels of older adults, taking into account their living environment.</p> Objective <p>The aim of our study was to compare the sarcopenia severity and physical fitness levels of nursing home residents and community-dwelling older adults using the ISarcoPRM diagnostic algorithm incorporating ultrasonographic measures.</p> Methods <p>Nursing home residents (NHR) (<i>n</i> = 51) and community-dwelling older adults (CDO) (<i>n</i> = 52) were included in this cross-sectional study. Participants’ physical fitness levels were assessed using the Senior Fitness Test (SFT). Sarcopenia severity was assessed using the 5r-Chair Stand Test (5r-CST) and hand grip strength (HGS), as well as the anterior thigh thickness (ATT) and Sonographic Thigh Adjustment Rate (STAR) obtained from ultrasonographic measurements. Participants were defined as nonsarcopenic, sarcopenic, and dynapenic according to the ISarcoPRM diagnostic algorithm of Kara et al.</p> Result <p>In our study, it was seen that individuals in NHR and CDO showed a homogeneous distribution in terms of sarcopenia severity (<i>p</i> &gt; 0.05). When the groups were compared, the ATT, STAR, HGS and 5r-CST values of NHR were lower than CDO (<i>p</i> &lt; 0.05). When comparing the groups, the physical fitness of NHR was lower than that of CDO according to SFT parameters (<i>p</i> &lt; 0.05).</p> Conclusion <p>The results of our study showed that geriatric individuals living in NHR had higher levels of sarcopenia and lower levels of physical fitness than CDO. We believe that this result is due to the fact that NHR are dependent on caregivers in the institution where they live for their self-care and daily living activities.</p> Clinical trial code <p>NCT06394648</p>