Frailty and Muscle Strength Tests in Older Adults Undergoing Major Surgery

The goal of this observational study is to learn if simple tests for frailty and muscle strength can help predict which older adults (age 65 and older) are at higher risk for problems after major abdominal surgery. The main questions it aims to answer are: * Do measures of frailty and muscle strength, taken before surgery, predict complications after surgery? * Can these tests be easily done during a routine pre-surgical visit? Participants will: * Complete brief tests measuring muscle strength, breathing strength, physical function, nutrition status, body composition, and memory during a regular pre-surgical clinic appointment. * Allow researchers to review their medical records 30 and 90 days after surgery to identify any complications or health problems.

Inclusion Criteria: Participants may be eligible for this study if they meet the following conditions: * Age 65 years or older. * Scheduled for elective (planned, non-emergency) major abdominal surgery, including colorectal, hepatobiliary, gynecologic, or urologic procedures. * Able to attend a routine preoperative evaluation visit. * Able and willing to complete brief assessments for muscle strength, walking, breathing strength, memory, and nutrition. Exclusion Criteria: Participants will not be eligible for the study if they have any of the following conditions: * Surgery is an emergency procedure. * Unable to walk independently (for example, dependent on a wheelchair or bed-bound). * Significant cognitive impairment that prevents understanding or completing study tests.