Keep Moving. Facts on Fitness Part 2
The story of ageing can be a bit of a sad one if left to its own devices. However, there are some significant players that can mitigate its effects on our health and wellbeing. In this three-part blog, we look at what the science has to say about how exercise can help maintain our health as we age. Part 1 focused on how physical activity impacts heart health, blood pressure, diabetes and cancer. This week looks at muscles, metabolism, bone density and arthritis.
Flex those muscles
Ageing is unfortunately accompanied by a loss of muscle, known as sarcopenia, and surprisingly, we aren’t very old when it starts. From around the age of 30, men and women lose muscle mass at a rate of 3-8% per decade. By about 50, that rate accelerates to 15%. In one study, this decrease in muscle mass was found to translate into 40% of women aged 55 to 64 years old not being able to lift 4.5 kg (1). However, if we exercise muscle, we can prevent and even reverse this process, and studies have found that resistance training is particularly effective. This type of exercise involves the muscles contracting against an external resistance, which leads to increases in strength, mass and/or endurance. It can be beneficial at any age. One study examined the effects of a resistance exercise program on people aged 68-86 years old. They performed 2-3 sets of exercises with 8-15 repetitions, three times a week for twelve weeks. The upshot was a significant increase in muscle strength to 5.7 kg and improvements in physical performance, balance, chair stand and gait speed (2).
Resistance exercise involves using anything that causes the muscles to contract. There's no need to head to the weights' section of your local gym if that's not your thing. Exercises that incorporate water bottles, cans of food, rubber (resistance) bands and your own body weight can all work very effectively to counteract the age-related muscle loss that starts in our 30s.
Metabolism and middle-age spread
The loss of muscle as we age isn’t a stand-alone phenomenon. Unfortunately, with a decrease in muscle mass, comes a decrease in resting metabolic rate (about 5% per decade) which contributes to weight gain - you may eat the same daily calories as you always have but not all the calories get used up like they used to and instead get converted to fat. The good news is that by building muscle back up with resistance training, the calories can get burnt, thus increasing metabolism and helping avoid that weight gain. In addition, the muscle fibres need energy to work, not only during, but also after, a workout. This maintenance and repair of muscle can increase metabolic rate for up to 3 days after a workout. One study reported that ten weeks of resistance training could increase resting metabolic rate by 7% and reduce fat weight by 1.8 kg (3).
In short, maintaining muscle by working it, can help avoid the constant dieting that is often done in an attempt to maintain a previous weight.
Bone density and osteoporosis
For women, menopause and declining oestrogen are factors which also impact our health as we age. Oestrogen helps protect bone strength. As much as half of a woman’s total bone loss occurs within the first 10 years following menopause. Osteoporosis is a disease of low bone mass and deterioration which leads to fragility and an increased risk of fracture. It is responsible for approximately 1.66 million hip fractures worldwide, every year (4). A meta-analysis of 43 randomised controlled trials with 4320 participants found exercise to be a safe and effective way to prevent bone loss in postmenopausal women (5). A 2018 paper reviewed the scientific literature and found consistent evidence that strength training alone or in combination with high impact training done at least 3 times a week were effective interventions for bone health (6).
Unfortunately, about half of women decrease their regular exercise during middle age. However, as summed up in one paper, “The most important, noncontroversial and simple thing everybody can and should do is to exercise” (7).
Rheumatoid arthritis (RA) is an autoimmune disease which causes joint pain, stiffness and swelling and can lead to permanent structural joint damage and deformity. It affects approximately 1% of the general population and is most prevalent in individuals aged 40 years or older, with the risk being 2-3 times higher in women (8). A 2011 review article reported that both aerobic and resistance exercise were beneficial to patients with RA and had no adverse effects. The authors encouraged all patients to include some form of exercise in their routine care (9).
Although moving stiff and painful joints may not seem logical, the Arthritis Association recommends doing a range of different types of exercise, as research shows that physical activity can help relieve symptoms and improve function (10).
In summary, exercise is one component of our lives that should be given priority if we wish to maintain or improve our strength, weight, bone and joint health as we age. Consistency and habit are key, although not always easy. The secret to forming any habit is to find something you love doing. Go on a journey of discovery and try your hand at all sorts. Perhaps do it with a friend so there is accountability and support for one another.
In the final part of this blog, we will look at how exercise impacts our memory and mental health.