Comparing Muscle-Building Effects of Beef and Plant Protein in Older Adults with or without Frailty Using a New Testing Method

What this Trial Is About

Researchers are studying the anabolic response to beef versus plant protein in older adults aged 65 to 95 years, including those who are frail, pre-frail, or non-frail. The study aims to understand how different protein sources affect protein and amino acid synthesis in the body, especially considering that older adults may have higher protein needs and a reduced anabolic response to meals. This research is important because many older adults choose to avoid animal products like beef, which has high levels of essential amino acids and anabolic benefits. Participants will consume three types of nutrition in a randomized, cross-over design beef protein, tofu soy protein, and water as a placebo. The feeding is given in small bites and sips every 20 minutes over a 5-hour period during study visits. The study includes one screening visit and four study days, where various assessments like body composition, muscle function, and walk tests are performed. Some procedures may be skipped if recently completed. During visits, participants will be fasted and have vital signs and blood samples taken before and during feeding. Researchers will measure anabolic responses using stable isotope tracers and assess amino acid bioavailability. The primary outcome is the capacity for protein and amino acid synthesis after consuming beef and soy protein. The total time commitment includes the initial screening and study days, with data securely stored for analysis.

Anabolic Response to Beef vs Plant Protein in (Pre)Frail Older Adults Using a Novel Stable Isotope Pulse Method