The body does not send notice. As we age, quietly, the body begins a slow withdrawal, not dramatically, nor all at once, just beneath the threshold of daily awareness. Muscle mass declines at a rate of three to eight percent per decade from the age of thirty, with the rate accelerating after sixty (Volpi, Nazemi & Fujita, 2004[1]). The weight on the scale may hold steady for years, but what it is made of is another matter entirely. The strength of the body that one took for granted becomes less reliable, recovery from exertion takes a little longer, and something in the body’s interior economy has shifted. Irwin Rosenberg gave it a name in 1989: sarcopenia. Borrowing from the Greek word for the loss of flesh, it describes the involuntary loss of skeletal muscle mass and the strength that makes activity possible.
What shifts is not obvious from the outside; as muscle mass declines, fat infiltrates into and around muscle tissue simultaneously (Goodpaster et al., 2001[2]). This is the deeper, visceral fat that settles around the abdominal organs; it is metabolically active and quietly compounding other health risks (Huffman & Barzilai, 2009[3]). Because muscle is expensive tissue to maintain, the body adjusts its housekeeping accordingly, but these are not isolated changes… each shift in muscle composition alters the conditions under which the next shift occurs, so that the process is less a straight line than a slow, self-reinforcing drift (Kalyani, Corriere & Ferrucci, 2014[4]).
Roger Fielding (2011) pressed the definition of sarcopenia further, arguing that mass alone tells only part of the story. It is muscle function (how the body bears its own weight, how confidently it moves, how readily it recovers) that carries at least as much consequence in lived experience. Alfonso Cruz-Jentoft brought this understanding to an international scale, in the European Working Group on Sarcopenia in Older People (EWGSOP)’s landmark consensus paper of 2019[5]. The EWGSOP established that sarcopenia is the progressive, generalised loss of skeletal muscle mass, strength, and physical function, associated with increased risk of falls, fractures, frailty, and mortality. The definition also clarified that sarcopenia is not simply a late-life phenomenon; it can emerge in midlife, shaped by genetics, lifestyle, and chronic illness long before the years most people associate with physical decline.
In the first part of this essay series, we explored briefly how physical mobility and cognitive function are caught in a loop with each other; each one shaping the conditions under which the other either flourishes or declines. Sarcopenia sits at the centre of that loop. Research has found sarcopenia to be independently associated with depression and cognitive impairment (Yogesh et al, 2025[6], Xu et al., 2025[7]). The body and mind are not simply connected; they are caught in the same feedback loop, each one capable of hastening what is happening in the other.
Sarcopenia: Prevalence and Concerns
The scale of that loop, and what it looks like in a real population, was explored in a study conducted at a tertiary care centre in Gujarat in 2023 (Yogesh et al, 2025). Across 407 participants, the overall prevalence of sarcopenia was 49.9%, i.e., nearly one in two older adults. The numbers rose with age and rose more steeply in women; in the 65–74 age group, prevalence was similar between males (41.3%) and females (43.8%), but in the oldest group, aged 85 and above, the figures were 45.5% in males and 65.5% in females, suggesting that older women may be at particularly high risk for sarcopenia.
In this study, those with sarcopenia scored significantly higher on depression scales; 66% met criteria for depression compared to 42.2% in the non-sarcopenia group, meaning sarcopenic individuals were more than twice as likely to be depressed. Cognitive impairment was nearly twice as prevalent in the sarcopenic group. Anxiety symptoms were more common, though the association did not reach statistical significance. Similarly, loneliness recorded was also somewhat higher in sarcopenic group (43.8%) than in those without sarcopenia (31.9%). The findings confirm that sarcopenia is independently associated with higher rates of depression and cognitive impairment in an Indian population, although these conditions are present across both sarcopenia and non-sarcopenia groups. The association with sarcopenia is one of degree of increased risk. What it may mean for how we understand and respond to healthy ageing, is something we will return to.
Sarcopenia Versus Other Forms of Muscle Loss
Sarcopenia is caused by factors inherent to skeletal muscle function itself: a reduction in functional motor units, decreased anabolic hormone levels, and declining protein synthesis. This distinguishes it from muscles loss after serious illness and systemic inflammatory processes (Kalyani, Corriere & Ferrucci, 2014), or from disuse atrophy, which follows inactivity and can be reversed more readily with exercise.
More specifically, sarcopenia is characterised by the selective reduced size and greater atrophy of type 2 muscle fibres, the fast-twitch fibres responsible for power, speed, and explosive movement (Lexell, 1995[8]; Nilwick et al, 2013[9]). The atrophy of type 2 fibres leads to a larger proportion of slow-twitch muscle mass in aged muscle, evidenced by slower contraction and relaxation times. This means that the will to move remains, but the machinery to do so has diminished. A person whose fast-twitch fibres have substantially atrophied may walk, dress, and conduct the ordinary routines of daily life without apparent difficulty, and yet find themselves hesitating at the top of a staircase, gripping a handrail with more intention than before, pausing before stepping off the pavement.
The body still receives the instruction; it is the response that has become less certain. That gap between intention and execution, between the self that knows what it wants to do and the body that can no longer quite match it, is one of the more quiet and less reported dimensions of what sarcopenia takes.
Amidst Loss and Decay, the Quest for Healthy Aging
Sarcopenia is a condition that does not necessarily announce itself through catastrophic illness. Rather, it alters the body’s capacities to act in the world and modifies one’s daily activities, although their erosion often goes unnoticed until they have already begun to narrow the horizon of what is possible.
For this reason, we would like to argue that central question of healthy ageing should not be lifespan but healthspan: the proportion of life lived in good health and with preserved function. The challenge is no longer merely to add years to life, but to ensure that those additional years are generative. Sarcopenia affects precisely those capacities that allow older adults to remain independent, socially engaged, and physically active. The significance of preserving muscle strength, therefore, extends beyond the prevention of disease. It concerns the quality of the years that longevity has already made possible.
It is in this context that resistance training (RT) has emerged as one of the most extensively studied interventions for healthy ageing (Hurst et al., 2022[10]). A scoping review by Govindasamy et al. (2025[11]) synthesized evidence from 36 studies examining the physiological effects of RT on sarcopenia risk among healthy older adults. The review found substantial evidence that moderate to high-intensity progressive RT improves muscle strength, power, physical performance, and functional capacity. Several studies also demonstrated favourable changes in body composition, including increases in lean body mass and skeletal muscle index. However, evidence regarding gains in muscle mass, gait speed, bone density, quality of life, and fall-risk reduction remained inconsistent. This means that RT can reliably enhance strength, although its effect in broader health outcomes is still unclear.
In a moment of caution, the authors emphasized the importance of appropriate exercise dosing. The caution is significant because discussions of resistance training can sometimes slide into a “more is better” logic. It reminds us that exercise, and in particular RT, is a controlled form of stress for the body. If it is introduced too abruptly or at too high an intensity, particularly in older bodies with slower recovery times, the immediate effects may be counterproductive. Acute muscle damage can temporarily impair mobility, increase fatigue, reduce confidence in movement, and potentially elevate fall risk during the recovery period.
What is noteworthy, however, is that this caution does not amount to an argument against resistance training. Govindasamy et al. (2025) underscore the importance of prescription. Resistance training functions much like a medicine: its benefits depend not only on the intervention itself but on the appropriate dose, frequency, intensity, progression, and supervision. The review repeatedly found the greatest benefits in structured, progressive programmes rather than in sporadic or excessively demanding exercise regimens. Equally significant is the finding that none of the studies included in the review reported adverse events associated with resistance training among healthy older adults. This suggests that when resistance training is carefully designed and progressively implemented, it appears to be a remarkably safe intervention.
The challenge, therefore, is not whether older adults should engage in resistance training, but how programmes can be tailored to balance adaptation and recovery, maximising gains in strength and function while minimising the risks associated with overexertion. This nuance is especially important if resistance training is to be promoted as a strategy for extending healthspan rather than merely delaying physical decline. Thus, the importance of the research on health ageing lies not in the promise of defeating time. Ageing will continue to alter the body in ways that no intervention can fully prevent. What resistance training offers is something more modest and perhaps more valuable: the possibility of preserving function for longer. The goal is not to escape ageing, but to inhabit it differently; to retain, for as long as possible, the strength, mobility, and confidence that allow us to remain participants in our own lives.
References
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[2] Goodpaster, B. H., Carlson, C. L., Visser, M., Kelley, D. E., Scherzinger, A., Harris, T. B., Stamm, E., & Newman, A. B. (2001). Attenuation of skeletal muscle and strength in the elderly: The Health ABC Study. Journal of Applied Physiology, 90(6), 2157–2165. https://doi.org/10.1152/jappl.2001.90.6.2157
[3] Huffman, D. M., & Barzilai, N. (2009). Role of visceral adipose tissue in aging. Biochimica et Biophysica Acta, 1790(10), 1117–1123. https://doi.org/10.1016/j.bbagen.2009.01.008
[4] Kalyani, R. R., Corriere, M., & Ferrucci, L. (2014). Age-related and disease-related muscle loss: the effect of diabetes, obesity, and other diseases. The Lancet Diabetes & Endocrinology, 2(10), 819–829. https://doi.org/10.1016/S2213-8587(14)70034-8
[5] Cruz-Jentoft, A. J., Bahat, G., Bauer, J., Boirie, Y., Bruyère, O., Cederholm, T., Cooper, C., Landi, F., Rolland, Y., Sayer, A. A., Schneider, S. M., Sieber, C. C., Topinkova, E., Vandewoude, M., Visser, M., Zamboni, M., & Writing Group for the European Working Group on Sarcopenia in Older People 2 (EWGSOP2), and the Extended Group for EWGSOP2 (2019). Sarcopenia: revised European consensus on definition and diagnosis. Age and ageing, 48(1), 16–31. https://doi.org/10.1093/ageing/afy169.
[6] Yogesh, M., Dave, A., Kagathara, J., Gandhi, R., & Lakkad, D. (2025). Prevalence of Sarcopenia and Its Association with Mental Health Status in Elderly Patients: A Comparative Cross-sectional Study. Journal of mid-life health, 16(1), 51–59. https://doi.org/10.4103/jmh.jmh_154_24
[7] Xu Z, Ma Y, Ning H, Jia S, Zhang G, Xia X, Hu F, Ge M, Liu X and Dong B (2025). Associations between sleep disorders, anxiety, depression, and the phases of sarcopenia to severe sarcopenia: findings from the WCHAT study. Front. Public Health, 13:1539729. doi: 10.3389/fpubh.2025.1539729
[8] Lexell, J. (1995). Human aging, muscle mass, and fiber type composition. The journals of gerontology. Series A, Biological sciences and medical sciences, 50 Spec No, 11–16. https://doi.org/10.1093/gerona/50a.special_issue.11
[9] Nilwik, R., Snijders, T., Leenders, M., Groen, B. B., van Kranenburg, J., Verdijk, L. B., & van Loon, L. J. (2013). The decline in skeletal muscle mass with aging is mainly attributed to a reduction in type II muscle fiber size. Experimental gerontology, 48(5), 492–498. https://doi.org/10.1016/j.exger.2013.02.012
[10] Hurst, C., Robinson, S. M., Witham, M. D., Dodds, R. M., Granic, A., Buckland, C., De Biase, S., Finnegan, S., Rochester, L., Skelton, D. A., & Sayer, A. A. (2022). Resistance exercise as a treatment for sarcopenia: Prescription and delivery. Age and Ageing, 51(2), Article afac003. https://doi.org/10.1093/ageing/afac003
[11] Govindasamy, K., Rao, C. R., Chandrasekaran, B., Parpa, K., & Granacher, U. (2025). Effects of resistance training on sarcopenia risk among healthy older adults: A scoping review of physiological mechanisms. Life, 15(5), 688. https://doi.org/10.3390/life15050688
Rollen Frantz
Rollen Frantz is a clinical and sport nutrition expert who focuses on integrated health. He has a masters in science and a diploma in the field of exercise science, yoga and exercise physiology. He is the Director of Zeeva Fitness and Health Care (Zeeva Fitness LLP). In 2024, he was awarded for his work in leardership at the Health 2.0 Conference in Dubai, for the goal of 'Making The Difference'.
Sabah Siddiqui
Dr. Sabah Siddiqui is Assistant Professor of Psychology at the School of Interwoven Arts and Sciences, Krea University, India. She is the author of Religion and Psychoanalysis in India (Routledge, 2016). Sabah has co-curated special issues for Psychoanalysis, Culture & Society (2024) and the Annual Review of Critical Psychology(2018). Her research engages critical psychology, psychoanalysis, and the politics of mental health, with a focus on gender, culture, and care. She is co-editing a volume on Ageing and Wellbeing in India: Phenomenological and Psychoanalytic Perspectives for Routledge (forthcoming in 2027).