Why are we doing the NUTRIMAL project?

The NUTRIMAL project is going to be a lot of work and is going to cost a lot of money. So…why are we bothering?

Muscle mass and strength decline with age…and this is a BIG problem

Beginning in our forties we lose ~1% of our muscle every year. For an average man that’s the equivalent of losing a 10oz steak of muscle every year [2]!


Strength is lost even faster, at a rate of about 2-3% per year [3]. This can make physical tasks like walking and rising from a chair more difficult. This loss of muscle mass and function is called sarcopenia.

Sarcopenia is big problem because it increases the risk of physical disability, falls and hospitalization [4,5]. Importantly it also reduces quality of life in older adults [6].

Sarcopenia cartoon


Therefore, is it critical that we identify strategies to slow the loss of muscle mass and strength with age in order to promote independence and well-being amongst older adults.

What do we know already?

Nutrition plays an important role in helping to slow the loss of muscle mass and strength with age.

Previous research studies have reported that:

  • Increasing milk protein in the diet can improve physical performance in older adults [7].


  • Proteins seem to be especially effective for increasing muscle building if they are high in leucine [8]. Leucine is one of the building blocks that makes up protein in foods and is known to have a special role as a ‘trigger’ for muscle building.


  • When older adults were supplemented with fish oil for 6 months they had an increase in muscle mass and strength [9].

gel capsules

What will the NUTRIMAL project tells us?

We want to find out:

  1. If consuming milk protein and extra leucine can slow the loss of muscle mass and strength loss with age
  2. If consuming milk protein, extra leucine AND fish oil is even more effective than milk protein and extra leucine alone

The results of the NUTRIMAL project will help to identify nutritional strategies to assist older adults in preserving their muscle mass and strength. This in turn could help to prevent physical disability and support independent and healthy aging. 

Overview of the NUTRIMAL project

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.