NUTRIMAL is a nutrition and healthy aging research project that is currently ongoing in University College Dublin.
The aim of the NUTRIMAL project is to investigate whether a food-based nutritional supplement can improve muscle mass and strength in men and women aged 65 and over who have low muscle mass and/or strength.
In this study we will recruit 120 men and women and will randomly assign them to consume a fruit-flavoured drink containing either:
1) Milk protein
2) Milk protein plus fish oil
3) A placebo (no milk protein or fish oil)
Participants will be asked to drink their allocated beverage twice per day (once with breakfast and once with lunch) for 6 months. We will test whether participants improve the amount of muscle they have (their muscle mass), their strength and their physical performance after 6 months of supplementation.
How will we measure changes in muscle mass, strength and physical performance?
Muscle mass: Changes in muscle mass will be measured using a DXA scan (stands for dual-energy x-ray absorptiometry). This is the same scanner used to perform a bone density scan but it can also tell us how much fat and muscle is in the body.
Muscle strength: We will measure upper body strength using a device called a handgrip dynamometer. Participants are asked to squeeze the handgrip as hard as possible. We will measure leg strength using a Cybex. The participant sits on the Cybex chair and their leg is strapped to a metal arm. The participant is then asked to kick their leg out as hard as possible to measure the maximum strength.
Handgrip dynamometer Cybex
Physical performance: Being strong and having lots of muscle is important but what matters most is muscle function. Muscle function or physical performance refers to the ability of an individual to perform basic physical tasks like getting out of a chair, walking or balancing. To test physical performance we use a set of tests: 1) balance tests, 2) a walking speed test, 3) a test to see if the participant can rise from a chair 5 times in a row (without using their hands!).
Optional additional measurements: The rate of muscle building
Of the 120 men and women that participate in the NUTRIMAL project, 39 participants will also take in an additional, optional measurement.
We think that the milk protein and fish oil will improve muscle mass in the NUTRIMAL participants by increasing the rate of muscle building . To test this theory we are going to measure to rate of muscle building in 39 of the participants. We will do this on two occasions: 1) before the participants begin the supplements and 2) in the final week of the 6 months of supplementation.