Exercise remains a powerful tool in preserving physical fitness during aging

Exercise remains an essential and powerful antiaging intervention, as demonstrated in a study published in the Proceedings of the National Academy of Sciences (PNAS) [1]. Led by Juliane Cruz Campos of the Institute of Biomedical Sciences at the University of Sao Paulo, the investigators examined the mechanisms that preserve physical fitness during aging in those who regularly exercise.

It is well known that during exercise, the mitochondria in the cells undergo transient or temporary changes in their function and metabolism. These changes are necessary for fine-tuning the roles of different organelles in the cells. Earlier reviews [2] demonstrate that physical exercise is associated with increased energy expenditure, which in turn has a high impact on the metabolism of the mitochondria. During exercise training, the mitochondria synthesise more ATP to address the metabolic requests of the cells.

Exercise also prevents the aging of the cells by boosting the mitochondria. One study [3] even pointed out that aerobic exercise, such as jogging for 30 minutes five days a week, can reduce cellular aging by nine years. Further, the authors of this study claimed that there was a reduction in the shortening of telomeres following weekly running exercises. Telomeres are indicators of the lifespan of cells.

Telomeres are regarded as markers of the biological age of an organism and cells. These structures are described as protective caps found at the ends of chromosomes or the structures that hold the DNA. Telomeres shorten as one ages. When they become too short, they cannot protect the cells, which can lead to cellular death.

In contrast, lack of exercise and poor lifestyle factors, can hasten the shortening of telomeres through oxidative stress. Oxidative stress is the inability of the cells in the body to offset the damage caused by radicals.

The study’s findings, published in the Preventative Medicine journal and conducted by Prof. Larry Tucker of Brigham Young University, showed that physical activity is critical for protecting cells against cellular aging.

How does exercise preserve physical fitness as one age?

Campos and colleagues investigated the mitochondrial dynamics during exercise using an animal model organism, the roundworm (Caenorhabditis elegans). After a single exercise session, mitochondria in the body-wall muscles fragmented but fused after recovery.

Investigators observed that daily exercise sessions delayed the fragmentation of the mitochondria and the decline in physical fitness that occurs as one age. To promote physical fitness, proper mitochondrial dynamics must be maintained.

How does exercise preserve physical fitness as one age?

The study authors found that the AMP-activated protein kinase (AMPK) was constantly activated, which is necessary to preserve physical fitness during aging. The AMPK acts as a sensor of the cell in determining the energy balance within the cells. Activating the AMPK would ensure an appropriate balance of energy within the cells.

When mitochondrial fission (fragmentation) or fusion is impaired, the AMPK function is also affected. However, constant and daily exercise ensures that mitochondrial fusion and fission are not impaired.

Further, AMPK has been shown in the study to regulate mitochondrial dynamics and enhance muscle function. Hence, regular exercise can promote physical fitness by regulating mitochondrial dynamics.

Promoting physical fitness is associated with longevity and wellness during aging. Engaging in daily exercise could promote AMPK activation and mitochondrial function, which in turn promotes muscle function and physical fitness during aging.

What types of exercise are best for older individuals?

Walking

It is acknowledged that age-related changes and chronic illness can reduce exercise capacity and hinder the ability of older people to achieve the recommended physical activities per week. However, there is one exercise regimen that older adults can do without special equipment or requires strenuous activities. One can start walking at least 10 minutes daily, preferably in nature.

Walking remains an essential but simple exercise that one can do later in life. A study that recruited octogenarians (85 years old and above), demonstrated that walking at least an hour or 60 minutes per week is associated with increased longevity in older adults aged 85 years and older [4]. Walking at least 10 minutes daily, six days a week can help increase longevity in older adults.

The World Health Organisation has recommended that adults should engage in at least 75 minutes of vigorous-intensity exercise per week regardless of age. However, in older adults, physical activity declines as sedentary time increases. One of the study’s authors on older adults, Dr Moo-Nyun Jin from Seoul, Korea, reiterates that older adults are less likely to meet the recommended physical activities. However, the results of their study revealed that walking for at least 10 minutes every day is sufficient to improve physical health and well-being and increase longevity.

What types of exercise are best for older individuals?

The study [4] investigated the association between risks of all-cause and cardiovascular mortality and walking amongst older adults aged at least 85 years old and older. Using the Korean National Health Insurance Service (NHIS) Senior database, the researchers obtained information on 7,047 adults (at least 85 years old and older) who underwent a national screening programme from 2009 until 2014.

Participants of the study completed a questionnaire that examined their leisure time physical activity, which included walking, cycling and running. Results revealed that 68.3% of the participants were women, and the average age was 87.

Findings revealed that those who walked at least one hour each week had a 40% lower relative risk of all-cause mortality and 39% lower risk of cardiovascular mortality compared with inactive individuals.

One of the study’s authors, Dr Jin, observed that “walking was linked with a lower likelihood of dying in older adults, regardless of whether or not they did any moderate-to-vigorous intensity physical activity. Identifying the minimum amount of exercise that can benefit the oldest old is an important goal since recommended activity levels can be difficult to achieve. Our study indicates that walking even just one hour every week is advantageous to those aged 85 years and older compared with being completely inactive. The take-home message is to keep walking throughout life.”

Yoga

Yoga is another physical exercise that can promote longevity and healthy aging. In a review [5] published in the Advances in Geriatric Medicine Research, lead author Madhivanan expressed that yoga has positive effects on mobility, mental health, balance, cellular aging and prevention of cognitive decline.

Yoga can be traced to at least 1000 BCE, with source texts defining various postures, meditation, breath control and spiritual practices. Recent interventions have adopted yoga for different health conditions, including problems associated with aging.

The review found that recent research studies have shown that yoga is associated with positive changes in the biomarkers of cellular aging. For example, oxidative stress markers, known to increase cellular aging, DNA damage, shortening of telomeres and shortening of cellular clocks, were all managed and reduced following consistent yoga practice in adults.

Among seniors, yoga has also been effective in maintaining functional independence and physical mobility in older adults. Other studies examined in the review also showed that yoga-based exercise interventions were associated with improved balance, reduced risk of slips or falls, better mental health functioning, increased flexibility and decreased back pain.

Older adults tend to have positive attitudes towards yoga and find this intervention highly acceptable.

Due to the impact of yoga practice on longevity and delaying aging, this intervention must be implemented in the community setting. Madhivanan pointed out that “since the cost of implementing yoga-based community and home-based interventions is low- policymakers are also eyeing yoga practice as a cost-effective way to reduce medical costs and improve outcomes among a growing aging population.”

Nature walks

Walking in nature is another way of maintaining healthy aging and promoting longevity. Exposure to nature for at least 10 to 20 minutes a day could help reduce stress, improve physical functioning and improve mental health and well-being.

The benefits of a nature experience have been well documented. One of the benefits includes delayed aging and its associated physical activity decline, reduced mobility and impairment of cognition.

Exposure to nature increases hormones or neurotransmitters such as serotonin and dopamine that improve mood. The constant release of these neurotransmitters would explain why exposure to the environment elicits positive mood and well-being.

Longevity and exercise

Exercise is well-established to be important in improving physical health and well-being. The publication of many studies in the past years provides additional evidence that exercise is associated with maintaining physical fitness even as one age. Hence, the fear of aging and its associated physical decline could be averted by following a regular exercise regimen.

Recent studies have shown that walking for as little as 10 minutes a day for 60 minutes per week improves physical fitness for older adults. These findings and recommendations are essential since older adults tend to experience a decline in their physical health, which might affect their ability to follow recommended guidelines for physical activities.

Due to the aging population in many countries, it is desired that those who grow older still maintain their physical health and wewell-beingCurrent evidence suggests that the key to a healthy lifespan and maintenance of physical fitness as one ages is simply walking. Hence, start brushing off the dust of your walking shoes and begin your journey to physical fitness!