Maintaining muscle mass with age: why it is important for healthy ageing

Muscle mass is often associated with sport, strength or appearance. For ageing, however, it is of interest primarily for another reason: muscles play a major role in determining how independent and resilient the body remains in everyday life.

As we age, muscle mass, muscle strength and the tissue's ability to respond to exertion change. These changes do not proceed in the same way in everyone. Physical activity, nutrition, illnesses and extended periods of physical inactivity can all play a role.

However, the figure shown by a body composition analysis is only part of the story. For physical function, muscle strength is particularly relevant. It helps determine whether we can climb stairs without difficulty, get up from a chair or carry a heavy object.

Research is therefore increasingly concerned with how muscle health can be maintained throughout the lifespan. Resistance training plays a central role. Adequate protein intake and regular everyday movement are also relevant, although none of these factors should be considered in isolation.

Muscle health does not mean having as much muscle mass as possible in old age. What matters is maintaining sufficient strength and physical function.

Contents

1. Why muscles are important for healthy ageing
2. What changes in muscles with age
3. Sarcopenia: when muscle loss becomes clinically significant
4. Why muscle strength tells us more than muscle mass alone
5. Resistance training as a stimulus for ageing muscles
6. Protein and muscle health
7. Why everyday movement complements training
8. Muscle health begins long before old age
9. What research cannot yet answer clearly
10. Conclusion
11. References

Why muscles are important for healthy ageing

Muscles enable movement. They stabilise the body, generate force and make everyday movements possible in the first place. At the same time, skeletal muscle tissue is a metabolically active organ involved in regulating glucose metabolism, among other things.

For healthy ageing, therefore, the amount of muscle tissue present is not the only point of interest. The more important question is how well the muscles continue to function.

This is particularly evident in everyday life. Getting up, walking, climbing stairs or carrying shopping bags require a combination of strength, coordination and endurance. When these abilities decline, a person's range of movement can gradually narrow.

Muscle health is therefore closely linked to physical function. However, it is only one part of a larger system that also includes cardiovascular fitness, balance, mobility and coordination.

Muscles are adaptable tissue

Skeletal muscles respond to exertion. When a muscle is used regularly, its structures and metabolic processes adapt to the demands. Conversely, changes can occur when such stimuli are absent for an extended period.

This relationship persists in older age. Although muscles lose some of their adaptability as we age, they are by no means fundamentally no longer trainable.

This is an important perspective on the topic. Muscle loss is not a process that must only be observed passively. At the same time, it would go too far to conclude that age-related changes can be prevented completely.

What changes in muscles with age

Ageing changes muscles on several levels. Muscle mass can decrease, tissue composition can change and the ability to develop force quickly can decline.

You can find out how to train your muscles specifically and structure your training appropriately as you age in our article "Resistance training in older age".

Neuromuscular control also plays a role. Muscles do not work independently of the nervous system. Movement results from the interaction of nerve cells, motor units and muscle fibres.

These structures can change with advancing age. Motor units can be lost or change their function, among other things. This can contribute to fewer muscle fibres being activated simultaneously and efficiently.

There are also changes within muscle cells. Mitochondria, which play a central role in energy production, also change over a lifetime. The regenerative capacity of muscle tissue can also be affected.

Muscle protein is constantly being built up and broken down

Muscles are not static tissue. Their proteins are constantly broken down and formed anew. These processes are known as muscle protein synthesis and muscle protein breakdown, respectively.

As long as formation and breakdown remain roughly balanced over time, muscle mass can remain relatively stable. Physical exertion and protein intake can stimulate muscle protein synthesis.

With advancing age, this response to certain stimuli can become weaker. Research uses the term anabolic resistance for this, among other terms.

This does not mean that older people no longer respond to training or protein. Rather, the muscles may need a sufficiently strong stimulus to trigger a comparable response.

Sarcopenia: when muscle loss becomes clinically significant

Not every decrease in muscle mass with age is automatically sarcopenia. The term describes a disease of skeletal muscle in which muscle strength in particular, as well as muscle quantity or quality and physical performance, are considered.

The European expert consensus EWGSOP2 placed particular emphasis on one important point: low muscle strength is considered a central feature. Reduced muscle quantity or quality supports the diagnosis, while impaired physical performance indicates a more severe situation

This has also changed the scientific view of muscle loss. Previously, more attention was paid to how much muscle mass a person had. Today, there is additional interest in what these muscles can actually do.

Muscle mass and muscle quality are not the same

Two people can have similar muscle mass and still develop different amounts of strength. The composition of muscle fibres, neuromuscular control and the ability to develop force quickly are relevant here, among other things.

Methods for measuring body composition also have limitations. A certain amount of lean mass does not automatically indicate how capable the muscle tissue is.

For the practical consideration of healthy ageing, a combination of different measures therefore makes sense. Body composition, strength and physical function complement one another rather than being equated with one another.

Why muscle strength tells us more than muscle mass alone

The importance of muscle strength becomes particularly clear in everyday movements. A person must not only be able to generate force. Often, this force must also be available within a short time.

Getting up from a chair is a simple example. The legs and hips must accelerate the body against gravity. In addition to existing muscle mass, nervous system activation and the speed of force development play a role.

Research therefore examines not only maximal strength but also the rate of force development. This describes how quickly a muscle can generate force.

A systematic review and meta-analysis in older adults showed that resistance training can improve both muscle strength and the speed of force development. The two adaptations did not proceed entirely in parallel, illustrating that strength and rapid force development reflect different properties of muscles.

This explains why a training programme should not be judged solely by whether the circumference of a muscle changes.

Resistance training as a stimulus for ageing muscles

Muscular adaptability is maintained even in older age. What matters is regularly receiving a stimulus strong enough to trigger adaptation.

Resistance training creates mechanical tension in muscle fibres. This is detected through various molecular signalling pathways and processed further within the cell. Among other things, it activates the mTOR signalling pathway, which is involved in regulating muscle protein synthesis.

However, the interaction is more complex than a single signalling pathway. The cell's energy state, the availability of amino acids and other signals also influence the muscle's response.

What research shows about resistance training

The evidence for resistance training in older age is now extensive. A systematic review with a network meta-analysis published in 2025 assessed 151 randomised studies involving a total of 6,306 older adults. The authors examined muscle mass, muscle hypertrophy, strength and physical function, among other outcomes.

Improvements were observed in several areas. Lower training volumes were already associated with improvements in physical function and lean mass, while higher training volumes showed advantages particularly in developing strength. The optimal workload therefore depends on the particular training goal.

Another meta-analysis from 2024 presents a similar picture. In 31 studies involving 1,744 older adults, higher training volumes were associated particularly with improvements in strength.

The findings therefore do not suggest that as much training as possible is automatically better. Even manageable amounts of training can provide a measurable stimulus.

The specific training programme should match the individual's level of performance. Individual guidance is particularly useful for existing illnesses, pronounced weakness or after a prolonged break from physical activity.

Protein and muscle health

Training provides the stimulus from which adaptation can arise. However, the body needs amino acids to build new muscle proteins.

Protein is broken down into individual amino acids in the digestive tract and then transported to tissues through the blood. The body can produce some of these amino acids itself, while others must be obtained from food.

Essential amino acids are particularly relevant to muscles. A central role is played by leucine. Among other effects, this amino acid can influence signalling pathways associated with muscle protein synthesis.

As we age, the muscles' response to a given amount of protein changes. This phenomenon is called anabolic resistance. It does not mean that protein becomes ineffective in old age. Rather, the response to an individual stimulus can be smaller.

How much protein makes sense?

Optimal protein intake depends on several factors, including age, body weight, physical activity and health status.

Scientific literature frequently discusses higher protein intakes for older people than for younger adults. As early as 2013, the PROT-AGE Study Group recommended a daily protein intake of at least approximately 1.0 to 1.2 grams per kilogram of body weight for many older people. Higher amounts may be appropriate with regular physical activity. Individual circumstances must be considered in certain illnesses, particularly when kidney function is impaired.

It is therefore important not to derive a blanket requirement for everyone from a general recommendation.

Distribution throughout the day is also being studied. A more even intake of protein-rich foods across several meals can be one way to provide repeated stimuli for muscle protein synthesis. However, the size of the long-term benefit of a particular distribution is less clear than the basic importance of adequate protein intake.

Everyday protein sources

Protein does not have to come from a particular food. Animal sources such as dairy products, eggs, fish and meat provide high-quality protein. Plant sources include pulses, soya products, nuts and grains.

With a predominantly plant-based diet, it can make sense to combine different protein sources. This can support the intake of various essential amino acids throughout the day.

For muscle health, it is not one individual food that counts. What matters is the overall diet and its combination with physical activity.

Why everyday movement complements training

Resistance training provides a targeted stimulus. However, the rest of the day also helps determine how much movement actually takes place.

Prolonged sitting and low physical activity mean that the muscles are used very little for many hours. Regular walking, climbing stairs, getting up and other everyday movements, by contrast, increase physical activity.

Everyday movement does not replace targeted resistance training. It serves a different purpose. While resistance training specifically loads particular muscle groups, everyday movement ensures that the body as a whole remains regularly active.

Resistance training and everyday movement complement one another.

This can also be used in practice. Someone who trains two or three times a week, for example, can plan walks, travel on foot or interrupt prolonged periods of sitting on the other days.

It is not only muscles that need movement

A varied active daily life engages different physical systems. Endurance activities provide different stimuli from resistance training. Balance exercises, in turn, address other abilities.

For healthy ageing, therefore, no single training style is decisive. Rather, a combination of different forms of movement suited to the person's situation makes sense.

This applies particularly when the goal is not outstanding sporting performance but physical independence over many years.

Muscle health begins long before old age

People thinking about muscle loss usually think of older people. Biologically, however, the story is longer.

Muscle mass and muscle strength are built up and changed over many years. The starting level in later life therefore also depends on how active a person has been over the decades.

This does not mean that early training guarantees a particular muscle mass in old age. However, it shows why muscle health does not only become relevant when the first limitations appear.

People who begin resistance training later can also adapt their muscles. A systematic review and meta-analysis from 2024, for example, examined the influence of resistance training on muscle size in older people. The analysis showed significant effects on the size of the muscles studied and on muscle fibre area. At the same time, the evidence for changes in lean leg mass was less clear.

This is an important distinction: a change in muscle structure does not necessarily have to be reflected in every measurement of body composition.

Starting later can also make sense

Muscle training is therefore not a measure that is relevant only to young people. Muscles fundamentally remain adaptable.

However, the workload should match the starting level. Someone who has not trained for a long time does not need to begin with a demanding programme. A gradual build-up allows the workload to be adapted to the person's own capacity.

In cases of pronounced symptoms, existing illnesses or marked physical limitations, training should be tailored to the individual accordingly.

What research cannot yet answer clearly

However convincing the data on resistance training, muscle strength and physical function are, some questions remain open. This applies particularly to whether targeted maintenance of muscle mass can actually influence overall lifespan or the incidence of certain illnesses.

Observational studies repeatedly find associations between muscle strength, muscle mass and various health parameters. However, this does not automatically establish that a particular form of training or a particular muscle mass causes these outcomes. People with greater muscle strength often differ in other respects from less active people. They may move more, eat differently or have fewer health limitations.

For research, the distinction between association and causation is therefore crucial.

Questions also remain unanswered in nutrition. Under certain conditions, higher protein intake can support muscle protein synthesis. Whether a persistently very high protein intake provides additional benefits for long-term health outcomes in healthy older people, however, has not been conclusively established.

What can nevertheless be said relatively clearly

Research presents a consistent picture of a basic relationship: muscles remain adaptable even in older age, and physical exertion can improve various muscular properties.

What is less clear, however, is which combination of training type, training volume, protein intake and everyday activity is optimal for each person.

This is also relevant because age cannot be equated with a uniform physical condition. A healthy 70-year-old can be physically much more capable than an inactive middle-aged person. Training programmes should therefore be based less on chronological age than on individual capacity.

Conclusion

Muscle mass is not an end in itself. Healthy ageing is primarily about maintaining strength and physical function for as long as possible.

Muscles, the nervous system and metabolism change with advancing age. These changes are part of normal ageing, but vary greatly between individuals. At the same time, muscles fundamentally remain trainable.

Resistance training can provide a targeted stimulus for muscles. Adequate protein intake supplies the amino acids needed for this. Regular everyday movement complements training and ensures that the body remains active outside individual training sessions as well.

Someone wishing to support their muscle health over the long term therefore does not need to train intensively every day. Rather, what matters is regularly providing physical stimuli and making movement a fixed part of everyday life.

Research points less towards a single perfect strategy than towards the interaction of several factors. Consistency is more important than perfection.

References

• Cruz-Jentoft AJ, Bahat G, Bauer J, et al. Sarcopenia: Revised European Consensus on Definition and Diagnosis. Age and Ageing. 2019;48(1):16-31.
• Liu CJ, Latham NK. Progressive Resistance Strength Training for Improving Physical Function in Older Adults. Cochrane Database of Systematic Reviews. 2009;(3):CD002759.
• Peterson MD, Rhea MR, Sen A, Gordon PM. Resistance Exercise for Muscular Strength in Older Adults: A Meta Analysis. Ageing Research Reviews. 2010;9(3):226-237.
• Morton RW, Murphy KT, McKellar SR, et al. A Systematic Review, Meta Analysis and Meta Regression of Protein Supplementation on Resistance Training Induced Gains in Muscle Mass and Strength. British Journal of Sports Medicine. 2018;52(6):376-384.
• Deutz NEP, Bauer JM, Barazzoni R, et al. Protein Intake and Exercise for Optimal Muscle Function with Aging: Recommendations from the ESPEN Expert Group. Clinical Nutrition. 2014;33(6):929-936.
• Beaudart C, Dawson A, Shaw SC, et al. Nutrition and Physical Activity in the Prevention and Treatment of Sarcopenia: Systematic Review. Osteoporosis International. 2017;28:1817-1833.