Is it possible to prevent or reverse muscle loss?
Yes, if you would exercise regularly and take good nutritional diet.
We know the importance of active lifestyle and exercise. And many of us already have the good habit of swimming, walking or jogging for a few times per week. However, these aerobic exercises are great for oxygenation and blood circulation but less so for muscle building and strengthening.
To improve muscle strength and function, we must add resistance training to our exercise routines. And take a bit of time to plan a healthy diet.
What is resistance training?
Resistance or strength training put your muscles to work by using hand-held weights, weight machines, resistance bands, resistance balls and even your own body. Pilates and yoga classes are two examples of strength-training workouts that use your own body weight to strengthen bones and muscles.
The Center for Disease Control and Prevention (CDC) recommends older adults to take part in muscle-strengthening activities for at least twice a week. You should exercise all the major muscle groups — the legs, arms, chest, shoulders, back, and abdomen. Ideally, you should work with a trainer who can guide you through a strength training program which is effective and safe.
If you like gardening, digging and shoveling are great for muscle strength too. Even mundane chores such as carrying shopping, vacuuming, and mopping floors, can be creatively included in your keep fit programme.
The 2014 International Sarcopenia Initiative2 carried out a review of published studies from January 2000 to May 2013. The aim was to find out the effects of exercise on muscle mass, strength and performance for people aged 60 and above. The conclusion was very positive that resistance training can improve muscle strength and function. However, its effect on building muscle mass was less consistent.
Resistance training can help both young and old people to increase muscle strength. Studies had been done to compare the muscle strengthening effects of two age groups which were given the same training programme. It was found that the strength gained by people between 70 and 80 years old was the same as that gained by those 20 to 30 years old. So, you are never too old to start working on your muscle.
Some health providers suggest exercise programme which combines aerobic, resistance, flexibility and/or balance training for overall health benefits and preventing fall.
What happens to a muscle undergoing resistance training?
When you start resistance training, the neural activity which stimulates muscle contraction increases. As you continue to practice, very soon you will notice an increase in muscle strength.
But muscle growth is due to a different mechanism. If you lift a heavier weight than what the muscle is normally used to, it will disrupt the cell structures of the muscle fibres. The body responds by sending out signals which activate a series of biological events to repair the damage. Protein synthesis in the muscle cell will produce more contractile proteins which cause the myofibrils to increase in size or numbers. The final result is thicker individual muscle fibre, and stronger muscle contraction.
Protein synthesis in the muscle is regulated by several substances including testosterone, growth hormones, and insulin-like growth factors. This helps explain why older people and women are unlikely to grow big muscles despite training. But their muscle strength will improve.
The response of muscle to the overload stress of resistance exercise begins immediately after each session. However, it may take several weeks or months before we see the result.
Why a balanced diet with high protein is important?
Resistance training alone is not enough to improve muscle strength. We need a good diet with adequate calories and rest. A well balanced diet should contain proteins, fats, carbohydrates, minerals and vitamins.
Muscle fibres are made of proteins. In health, proteins structures undergo a constant process of breaking down and rebuilding. Much like constructing different objects with Lego bricks, our body can build complex protein structures from 21 kinds of building bricks – the amino acids.
Our body is able to make most of these amino acids if conditions are satisfied. But there are 9 essential amino acids* which can only be obtained from food. That’s why we have to eat proper diet to make sure that the pool of amino acids, especially the essential amino acids, is regularly replenished.
Leucine is an essential amino acid which plays an important role in muscle protein synthesis. And HMB**, the metabolite of leucine, has been shown effective at preserving lean mass from breakdown. However, results of comparative studies are often conflicting. So, although Leucine and HMB supplements seem to have effects on muscle mass and function, further clinical trials are needed to confirm their efficacy for older people2.
How much proteins do we need?
Healthy adults are advised to take about 0.8 gram of protein per kilogram of their body weight each day. So, for a person weighs 70 kg, he or she should consume around 56 grams of proteins per day. Bear in mind though this is the minimal amount to prevent protein deficiency. For people such as athletes who train regularly and hard, their protein needs will be much higher.
But older people need higher levels of dietary proteins according to research published in the Journal of the American College of Nutrition3. It is because as we get older, we are less efficient at processing proteins and need to consume more to build the same amount of muscle.
Therefore, you should aim to get 1.0 to 1.2 g per kilogram of your body weight of proteins per day. And more if you are showing signs of muscle loss. Your doctor, or a dietician or nutritionist will give you good advice if you are not sure.
Proteins are available in both plants and animals: meat, poultry, fish, eggs, dairy, beans, legumes and nuts. So, you have plenty of choices to mix and match them in your meal plans. But make sure you take enough carbohydrate calories to provide your body with energy. Otherwise the proteins you eat will be used for energy instead of building muscle.
Sarcopenia is a major health problem associated with ageing. It has a debilitating outcome which might lead to loss of independence, institutionalization or prolonged hospitalization.
The subsequent increase in healthcare costs will be a great burden on individual family and society as the proportion of elderly increases in the population. This awful scenario could be prevented if we just take a bit of time to plan our diet and exercise.
It may be cliché, but prevention is really much better than cure.
*The 9 essential amino acids are: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.
**HMB = β-hydroxy β-methylbutyrate
- Borst SE. Interventions for sarcopenia and muscle weakness in older people. Age and Ageing 2004; 33: 548–555.
- Cruz-Jentoft, AJ, et al. Prevalence of and interventions for sarcopenia in ageing adults: a systematic review. Report of the International Sarcopenia Initiative (EWGSOP and IWGS). Age and Ageing 2014; 43: 748–759. https://doi.org/10.1093/ageing/afu115
- Chernoff, R. Protein and Older Adults. J Am Coll Nutr. 2004 Dec;23(6 Suppl):627S-630S.