Muscular power generated by participants will be measured using an App (Sit-to-stand App version 1.1) installed on an iPhone (Apple Inc., USA).

During the execution, subjects will sit on a rigid chair with their arms crossed over their chest with the hip, knee and ankle joints at approximately 90 degrees. Subjects will be asked to stand-up as fast as possible. Participants will complete three STS repetitions. No footwear will be allowed during the test.

Frailty Syndrome will be assessed according to Fried's Phenotype, which focuses on:

1. Handgrip strength
2. Usual gait speed
3. Weight loss
4. Exhaustion
5. Physical activity levels

Subjects who will result positive to three out of five criteria will be considered as "frail", whereas if they will result positive to only one or two of them they will be considered as "pre-frail". The absence of each criteria will be necessary to define a subject as "robust".

Sarcopenia will be assessed according to the recommendation provided by the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) (2019). This guideline focuses on the assessment of:

1. Leg muscle strength
2. Muscle mass quantity
3. Physical performance

The presence of low muscle strength levels will be considered as "probable sarcopenia"; the presence of low muscle mass and strength levels will be considered as "confirmed sarcopenia"; finally, the presence of the three criteria will be considered as "severe sarcopenia".

Researchers will measure subjects' calf and mid-upper arm circumference using a tape measure.

Subjects' clinical status will be assessed through a list of questions regarding:

• socioeconomic level
• educational level
• chronic pathologies
• smoking habits
• polypharmacy
• depression
• number of falls
• hospitalization
• self-perceived health status