Physical activity is better than any medication or any other lifestyle intervention in the prevention and treatment of many chronic diseases associated with ageing (heart disease, type 2 diabetes, high blood pressure, obesity, osteoarthritis, dementia and cancer). The rising global levels of inactivity are a likely cause of increasing obesity, dementia and cancer. Only 25% of the adult UK population get the recommended dose of muscle strengthening activities.
A sedentary lifestyle is associated with an increased cancer risk - for every 2 hours of sitting per day (sitting at a desk or watching TV), the risk of endometrial cancer increases by 10% and by 8% for colon cancer.
Strength / resistance training is just as important as aerobic exercise (brisk walking, running, dancing and cycling) in increasing healthspan and lifespan. Strength training is physical exercise that uses muscles to contract and work against a resisting weight or force. It can involve using body weight (push-ups, lunges and pull-ups) or may incorporate the use of resistance bands, cable machines, free weights (such as kettlebells, dumbbells or barbells) or weight machines.
Muscle strength typically peaks in our 30s and then starts to decline with age. Age-related muscle loss happens to everyone with about 5% lean mass lost per decade, accelerating after age 70, in individuals who do not strength train on a regular basis. Regular weight training (as well as aerobic exercise) throughout life is the best tool to combat neuromuscular decline and ensure your ability to keep carrying out everyday activities, recover from illness and injury as well as maintaining metabolic health and slowing down bone loss. Studies show that just 30-60 minutes of strength training per week are enough to reduce rates of heart disease and cancer.
One of the reasons that strength training improves our health is that it helps prevent frailty in the older adult population. Frailty syndrome is the progressive loss of strength and muscle mass and is associated with a decline in mobility and ability to perform activities to live independently. This decline in function is linked with an increased risk of falls, disability and mortality.
Beyond the benefits of muscle-strengthening activities for musculoskeletal health, strength training has been shown to have numerous additional health benefits.
Skeletal muscle plays an essential role in metabolism and glucose homeostasis - maintaining stable levels of blood glucose. Muscle, together with insulin, plays an important role in absorbing glucose from the blood - having increased muscle mass means you have a larger sink for excess glucose. People with increased muscle mass are less likely to develop insulin resistance - a condition associated with obesity, cardiovascular disease, non-alcoholic fatty liver disease, polycystic ovary syndrome and some cancers.
Another reason people with increased muscle mass have better metabolic health is that exercise increases the number and efficiency of mitochondria (energy producing parts of the cells). This, in turn, increases your ability to draw glucose from your blood, independently of insulin.
Research also shows that strength training is protective against neurodegenerative diseases like Alzheimer’s disease - specifically protecting parts of the brain involved in memory and learning.
Aerobic exercise improves most aspects of health, however has little impact on preventing bone loss. Strength training places an external load on bones, and stimulates bone forming cells. This helps to prevent the natural decline in bone density and prevent osteoporosis. Osteoporosis is a major risk factor for fractures in the older population. Hip fractures are especially debilitating - invariably associated with chronic pain, reduced mobility and decreased independence. In the one year after a hip fracture an individual’s risk of dying increases by up to 40% especially in males.
Both strength training and aerobic exercises boost our health in slightly different ways. Some people may be apprehensive about incorporating strength training into their lives, but even 30 - 60 minutes of simple resistance training exercises using body weight or resistance bands have benefits in preventing diseases of ageing. Doing something is better than nothing at all and it is never too late to start!