As we age, muscle mass and muscle strength decrease naturally. What we eat has an essential role in maintaining our muscle mass and slowing down this type of ageing.
Protein, in particular, signals molecules to initiate muscle synthesis, and provides the amino acids to build new muscle. With age, there is a decrease in sensitivity to stimuli that initiate this muscle synthesis. This is thought to be related to a number of reasons, including problems with digestion and absorption of nutrients, and hormonal regulation.
Exercise, specifically strength or resistance training also promotes muscle development. Use it or lose it, as they say. Furthermore, the combination of strength training and a good nutrition plan appears more effective than having a good diet alone. The timing of your protein intake is also important. Eating within an hour after strength training can make your muscle more sensitive to the effects of the protein too.
You can exercise at home and reap the benefits of regular strength training, without the dumb-bells or a gym membership. Your physiotherapist is the best person to give you direction on suitable exercises and the repetitions you can do using your own body weight.
Overall health
These exercises don't just affect your muscles. According to the American Council on Exercise, these exercises have a fundamental effect on overall health, such as reducing your blood pressure, improving your cholesterol levels and reducing your risk of diabetes.
They can also improve your ability to carry out everyday activities, such as lifting or moving things at home and in the garden, as your strength, co-ordination and flexibility improve.
Inadequate protein in older adults leads to a more rapid, unintentional loss of body weight and muscle. This loss of muscle mass and strength is called sarcopenia. The condition can very quickly affect functional capacity and quality of life.
Professor of exercise physiology and nutrition Luc van Loon of Maastricht University describes this loss of muscle strength, caused by immobilisation and other conditions such as type 2 diabetes, as muscle deconditioning.
There are multiple causes of nutritional frailty and weight loss. The release of cytokines during chronic disease is a significant factor. In addition to blunting the appetite, cytokines also contribute to the breakdown of fat stores and lean muscle mass in the body.
Protein quantity
The optimum quantity of protein to prevent or slow down the progression of sacropenia has yet to be determined. However, research findings suggest that protein intakes need to be moderately higher than the present recommendation of 0.8g per kilogram body weight per day, to see improvements in the muscle mass in older adults who strength-train.
Recent research suggests that dairy protein, especially whey protein, may help in the fight against sarcopenia because of its high concentration of leucine. This amino acid increases muscle protein synthesis.
Although the rate of muscle synthesis is lower in older than younger men after exercise, a recent study highlighted the rate of muscle synthesis did not differ significantly between men of different ages after the co-ingestion of protein and leucine.
More research is necessary to determine whether various sources of protein (animal and plant) differ in their ability to prevent or reduce sarcopenia.
In the meantime, a sound weight-gain programme combines an appropriate amount of strength exercise with a balanced diet to provide essential nutrients for muscle growth and to boost energy levels.
The constant addition of 250-500 extra calories each day can result in weight gain of a half to one pound per week. This might sound easy but in my experience some patients have little interest in food and need a lot of prompting and encouragement.
To avoid feeling over stuffed, small additions can be made to the normal diet. Those extra calories do add up. However, the impact of healthy snacks will be seen only if they are eaten in addition to, and not instead of, usual typical meals and snacks.
Calorie boosts
If you tend to fill up too fast, add small volumes of high-calorie foods to meals:
Each tablespoon of rapeseed, camelina or olive oil provides an additional 120 calories to your meal. Drizzle an extra one over salad leaves or into the pan while sautéing onions.
Other sources of healthy fats include thick slices of avocado and flaked oily fish (salmon and mackerel) or chopped anchovies. Add to salads or sandwich fillings.
Use fortified whole milk to make soups and sauces, in milk puddings and custard and make porridge with milk instead of water.
Enrich the milk even further by adding 2-4 tablespoons of skimmed milk powder to a pint of milk and use as regular milk.
Add grated cheese to mashed potatoes, wholemeal scones and melt over roasted vegetables to increase calorie and protein intake.
Eggs can be a useful additional protein boost to a meal. Soft egg is easy to swallow. Try cooking them in various ways to provide variety.
Add a heaped dessertspoon of honey to cereal, stewed fruit and porridge. It boosts the calorie count by 58kcal without adding much volume.
Two tablespoons (32g) of cashew butter provides 200kcal. Top oat cakes or rye crackers with nut butters or add two tablespoons to your morning smoothie to increase the protein content.
Snacks
Three handfuls (100g) of mixed nuts provide 620kcal. Eat as a snack between meals or add ground nuts into breads, salads, cereal or yoghurt.
A 130g pack of dried mango slices contains 430kcal. You can carry this with you as a convenient portable snack or chop it into a prawn and chilli salad.
A smoothie combining 1 cup fruit (such as bananas or berries), 1 cup vanilla frozen yogurt, ½ cup milk, ¼ cup juice, and 1 tablespoon ground flaxseed beats a cup of tea calorie wise.
A 100g pack of yoghurt-coated peanuts and raisins add 502kcal.
Snack bars such as Nature Valley or 9 Bars have about 200kcal each.
Guacamole, salsa and grated cheese on oat cakes.
Talk to your GP or dietitian if nutritional intake is still inadequate. There may be a role for certain foods intended for special medical purposes to boost your calorie and protein intake.
Paula Mee is lead dietitian at Medfit Proactive Healthcare and a member of the Irish Nutrition and Dietetic Institute.
pmee@medfit.ie
Tweet @paula_mee
