The Effect Of Movement As We Age
Article by Emilia Fish, BSC ANUTR
We have a population which is growing and living to an older age, so how can we contribute to health in those years? One way which the research has investigated is through keeping active (1).
In the context of this article physical activity refers to any bodily movement produced by the contraction of skeletal muscle that increases our energy expenditure above rest. Exercise refers to a subcategory of physical activity that is planned, structured, and has a purpose for the improvement or maintenance of physical fitness. I have used these words in context of the research they have come from but would like to recognise they can be triggering for some. Where possible I have used the word “movement” which I personally feel better reflects finding movements which are sustainable for us – we enjoy and fit into our lives. This can be anything from stretching, gardening, yoga, walking, hiking, running, strength training, swimming, getting off the train a stop early and so much more.
Physical fitness:
Physical fitness is the ability to conduct everyday tasks without undue fatigue and having enough energy to enjoy leisure time. This includes an integrated system of our muscles, heart and blood, and lungs – whereby our skeletal muscles perform work which requires energy. A by-product of this energy producing process is carbon dioxide which is carried in our blood and expired by our lungs (2,3).
Decline in our function as we age aging:
Decline in function as we age associated with a process called sarcopenia. This is when there is a loss of skeletal muscle mass, function, and potentially muscle quality (4). Research looking at the muscle quality in younger adult’s muscle compared to an older adult’s muscle, shows that in older adults the muscle has less well-arranged muscle fibres, and fat infiltration (5).
The consequence of this is slower muscle contractions, and the amount of power that can be generated at the same force is lower. This means that as we age our muscles become slower and weaker (6,7,8).
Effect of movement on our function as we age:
Research has investigated the effect of “sufficient exercise” on physiological function as we age. Overall, finding that an 80-year-old who performs sufficient exercise has the same VO2 max (a measurement to indicate cardiovascular fitness) as a 45-year-old who is sedentary, suggesting a 35-year functional advantage with sufficient exercise (9).
Another interesting study was performed on master weightlifters. This found that the amount of weight an individual could lift above their head did decline with age, however the oldest participant who was 87 years old, could lift 55kg above their head. Further, it was concluded that an 85-year-old weightlifter had the same power as a 65-year-old untrained control subject, representing an apparent 20-year functional advantage for the weight lifter (10).
This suggests that while there is a decline in function as we age, are absolute function can remain high through movement.
So, does exercise prevent the effects of ageing?
The simple answer is no, we cannot prevent the ongoing process of ageing. However, through movement we can improve our function so that while function continues to decline at a similar rate, it is on a different slope which hits the threshold of independence (where we need support for daily tasks) later in life. So no, exercise does not prevent ageing, but the way in which we age can be manipulated in the context of exercise (11,12).
Some of the other benefits of exercise":
Heart disease. A seminal study was conducted in the 1950’s looking at bus drivers and bus conductors in London. It found bus conductors, who were more active than bus drivers, had lower risk of cardiac events (13). Since then, the research has developed, and a recent review of the evidence showed that: any physical activity is better than none; meeting the American 2008 physical activity guidelines in (similar to that of the UK) reduces mortality and CVD risk to about 75% of the maximal benefit obtained by physical activity alone; and that physical activity beyond this has some but smaller additional health benefits (14).
Mental Health. Research shows physical activity is associated with reduced risk of mental ill-health. There appears to be a stronger relationship between physical activity supporting our mental health compared to work-related, travel and household physical activity, suggesting the domain in which physical activity occurs should be considered (15). Recent research in light of the COVID-19 pandemic on individual aged over 50-years-old found that loneliness and decreased physical activity were factors for worsening mental health, suggesting targeting these modifiable risk factors is important (16,17).
Physical activity guidelines for older adults
The NHS recommend doing some type of physical activity every day. For adults aged 65 and over, the advice is to (18):
• Aim to be physically active daily.
• Try to include activities to support strength, balance, and flexibility at least twice a week.
• Aim to limit sedentary time such as time spent sitting or lying down and try to break up long periods of inactivity with some movement.
• Aim for at least 150 minutes of moderate intensity activity a week or 75 minutes of vigorous intensity activity if you are already active. Or you could choose to do a combination of both!
Light activity includes incidental movement, such as cleaning, making the bed, moving around your home.
Moderate aerobic activity includes brisk walking, bike riding, and pushing a lawn mower.
Vigorous intensity activity makes it hard to say a few words without pausing for breath, and includes jogging/ running, fast swimming, singles tennis, and hiking uphill.
Remember, all movement is good for us, it is important to do what we can, and what is sustainable for us. Any activity is better than none. Speak to your GP if you have any concerns about exercising, including strength, injuries and falls.
Resources:
• Age UK. The leading charity for supporting older people (19).
• Mind UK. Physical activity and your mental health (20).
• National Health Service. Physical activity guidelines for older adults (18).
This blog post was written by Emilia Fish, a registered associate nutritionist, Food Science and Nutrition BSc graduate and current Clinical and Public Health Nutrition MSc student at UCL. She has worked in several nutrition internship roles, has experience in Food Science labs and enjoys sharing simple, evidence-based nutrition on @nutritionnourishment. Emilia enjoys sharing others nutrition journeys in her podcast, The Nutrition Nourishment Podcast: Sharing Our Journeys.
References:
1. https://link.springer.com/article/10.1186/2046-2395-3-9
2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2805364/
3. https://www.cdc.gov/physicalactivity/index.html
5. https://link.springer.com/article/10.1186/2046-2395-3-9
6. https://pubmed.ncbi.nlm.nih.gov/19464390/
7. https://link.springer.com/article/10.1007/s004240050215
8. https://link.springer.com/article/10.1007/BF00864218
9. https://physoc.onlinelibrary.wiley.com/doi/full/10.1113/jphysiol.2014.282863
10. https://pubmed.ncbi.nlm.nih.gov/12131263/
11. https://physoc.onlinelibrary.wiley.com/doi/full/10.1113/JP272443
12. https://www.frontiersin.org/articles/10.3389/fphys.2018.01135/full
13. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(12)61027-7/fulltext
14. https://pubmed.ncbi.nlm.nih.gov/31095084/