Is it possible to prevent or reverse sarcopenia?
Yes, if you would exercise regularly and take a good nutritional diet.
We know the importance of an active lifestyle and exercise. And many of us already have the good habit of swimming, walking or jogging a few times per week. However, these aerobic exercises are great for oxygenation and blood circulation but less for muscle building and strengthening.
We must add resistance training to our exercise routines to improve muscle strength and function. And take a bit of time to plan a healthy diet.
What is resistance training?
Resistance or strength training puts your muscles to work 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 Centers for Disease Control and Prevention (CDC) recommends that older adults participate in muscle-strengthening activities 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.
Digging and shovelling are also great for muscle strength if you like gardening. 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 determine the effects of exercise on muscle mass, strength and performance for people aged 60 and above. The conclusion was that resistance training could 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 have compared the muscle-strengthening effects of two age groups with 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. So, you are never too old to start working on your muscle.
Some health providers suggest an exercise programme combining aerobic, resistance, flexibility and/or balance training for overall health benefits and preventing falls.
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 number. 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 muscles to the overload stress of resistance exercise begins immediately after each session. However, it may take several weeks or months to 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, protein 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 can make most of these amino acids if conditions are satisfied. But 9 essential amino acids* can only be obtained from food. That’s why we must eat a proper diet to ensure that the pool of amino acids, especially the essential ones, 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, the results of comparative studies are often conflicting. So, although Leucine and HMB supplements seem to affect 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 grams of protein per kilogram of their body weight each day. So, a person weighing 70 kg should consume around 56 grams of protein daily. Bear in mind though this is the minimal amount to prevent protein deficiency. For 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. 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 daily. And more if you are showing signs of muscle loss. Your doctor, dietician, or nutritionist will give you good advice if you are unsure.
Proteins are available in plants and animals: meat, poultry, fish, eggs, dairy, beans, legumes and nuts. So, you have plenty of choices to mix and match in your meal plans. But make sure you take enough carbohydrate calories to give your body energy. Otherwise, the proteins you eat will be used for energy instead of muscle-building.
To conclude…
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 greatly burden individual families and society as the proportion of elderly increases. This awful scenario could be prevented if we take some time to plan our diet and exercise.
It may be cliché, but prevention is really much better than cure.
Notes:
*The 9 essential amino acids are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.
**HMB = β-hydroxy β-methylbutyrate
References:
- 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.