Last January, Karthik Venugopal hit what he calls "rock bottom". Having gained 5 stone over the previous decade Karthik (48) also had high cholesterol and his kidneys were showing signs of damage. Then the sudden death of his beloved mother in 2021 triggered a total health crisis. He felt so low he often struggled to get out of bed and was diagnosed with depression.
"Some days I felt so bleak I didn't want to live," explains Karthik, who works in risk management.
"I comfort ate and my weight gain increased. I felt terrible."
Not only was he at 17st 6lb (112kg) obese for his 6ft 3in height, his blood pressure was dangerously high at 160/112 (120/80 is normal).
Karthik's doctor wanted to put him on blood pressure medication and antidepressants, but he had other ideas. With a six-month-old son, Danush, to care for, Karthik believed the better option was to overhaul his lifestyle.
He joined his local gym and started weight training with a coach three times a week. He also committed to taking 10,000 steps a day and overhauled his diet — "ditching the cheesecake that had become my comfort food and sticking to lean proteins such as chicken, fish and eggs with plenty of vegetables", says Karthik.
"After three months I was down to 11st 9lb (76kg) and my waist had shrunk from 47in to 31in — I even had a six-pack...
"My blood pressure was down to a safe 116/76, my cholesterol dropped and my kidney function normalised. Plus, my mental health improved massively."
One year on, Karthik is still exercising. "My mood is so much better; I'm enjoying life again," he says.
"Best of all, I feel I have enough energy to be active for my son. I'm determined to keep this up, having proven I can stay happy and healthy with exercise alone — no pills."
The idea that exercise can treat some medical problems as well as, if not better than, medication is gaining momentum.
Earlier this year, a review by the University of Potsdam in Germany hailed exercise as the best treatment for depression, being at least as effective as drugs or talking therapies without the potential side-effects or waiting lists.
The conditions that respond to exercise are wide ranging. A recent study by Anglia Ruskin University showed that regular physical activity was as beneficial as drugs when it comes to treating premature ejaculation, for instance.
This can be added to the list of ailments — from high blood pressure and diabetes to dementia and arthritis — that exercise has been shown to improve.
In the face of such research, The Academy of Medical Royal Colleges in London pronounced physical activity a "miracle cure" for many common ailments. Its 2015 paper concluded exercise would reduce pressure on the NHS if doctors encouraged everyone to do it more.
And you don't need to run marathons to benefit. A 2019 review in the BMJ found that health improves with as little as 30 minutes of physical activity a week — however, more than a quarter of adults currently fail to achieve even this minimum.
"The sweet spot, identified by research," says Dr Lindsy Kass, a researcher in exercise physiology from the University of Hertfordshire, "is 150 minutes of moderate intensity activity [enough to raise your heart rate and get you a little out of breath] in bouts of 10 minutes or more."
With so much mounting evidence, she believes there should be broader acceptance that exercise is "an effective therapy that doctors can prescribe".
One of the lead researchers in this field, Bente Klarlund Pedersen, an exercise physiologist at the University of Copenhagen, goes a step further: "There's strong evidence that exercise decreases the risk of more than 35 disorders and that it should be prescribed as medicine for many chronic diseases, such as type 2 diabetes, dementia, cardiovascular diseases and cancer."
Doctors have long known that people who move more tend to be slimmer, have better mental health and a lower risk of chronic illnesses — and live longer. New data is revealing what exercise does at a cellular level — and exactly what makes the effects so powerful and wide-reaching.
"Research has shown the exertion of exercise places a small but positive stress on our body's systems, which forces the cells to adapt in order to cope with the demands being put on them," explains Professor Ian Swaine, a sport and exercise scientist at the University of Greenwich.
"This has the net result of making them work better and harder across every organ, meaning the entire body functions more efficiently."
In other words, repeated exercise keeps all the body's cells in optimal condition so they can cope better with life's everyday challenges. Yet there are specific areas of the body that can benefit, including the heart and, less obviously, the brain.
"Activity streamlines the 'plumbing' of the cardiovascular system, by making blood vessels stronger, more flexible and better able to pump blood around the body, which reduces strain on the heart and lowers blood pressure," says Prof Swaine.
This improved blood flow also means vital nutrients are delivered more effectively around the body. Neurologists have investigated whether this increased circulation to the brain helps prevent the cell death that's linked to dementia.
One 2018 study by the University of Gothenburg in Sweden found that middle-aged women with medium to high fitness levels had an eight times lower risk of developing Alzheimer's than those who didn't exercise.
Meanwhile, in 2021, Arizona State University researchers found that exercise could significantly slow deterioration in people who had already started to develop dementia.
Exercise also helps with blood sugar control. Our bodies break down the carbohydrates we eat into glucose (blood sugar), which the muscles use as fuel to move. The hormone insulin (released by the pancreas) is needed to remove glucose from blood into the muscle cells.
"Exercise releases specific enzymes that improve the sensitivity of our cells to insulin, so less insulin is needed overall," explains Dr Kass.
"This means the pancreas doesn't have to work as hard, which in turn reduces the risk of developing insulin resistance and type 2 diabetes. Exercise also helps reverse age-related decline in the function of our mitochondria — the tiny powerhouses in every cell that turn glucose into energy molecules."
This decline is worse in sedentary people, which can leave the mitochondria unable to burn off glucose, creating an excess of oxidants — molecules that damage our cells and DNA.
Poorly functioning mitochondria have been linked to fatigue, memory loss, heart disease and other chronic diseases. Despite such strong evidence, questions remain about how this research translates into specific prescriptions.
Last year the British government began a £12.7 million trial in which GPs around England prescribed activities such as walking or cycling as part of a wider movement of social prescribing that aims to refer more patients for non-medical activities. It's hoped the results of this three-year study will shed more light on whether being told to be more active works in practice, and if it can help reduce GP appointments and over-reliance on medication.
Sir Muir Gray, an NHS public health specialist, described the service as: "The single most important advance in therapeutics in my 50 years in medicine", adding that "every drug or psychological prescription for a long-term condition should be partnered by a prescription of activity".
Prof Swaine, however, cautions against people seeing exercise as a "replacement" for medication — especially without discussing it with your doctor — "not least as most people's ability to fit in exercise waxes and wanes during our lifetime — often unavoidably depending on other factors, such as looking after children or dealing with an injury", he says.
You can also have too much of a good thing. One 2015 study in the Journal of the American College of Cardiology found people who ran at a fast pace for more than four hours a week had about the same risk of dying during the study's 12-year follow up as those who hardly exercised at all.
However, Dr Kass stresses "most of us are in not in danger of over-exercising — so, the overall message that exercise will help almost any health problem holds true".
"Moving more every day is a free and easy way to take more control of your wellbeing," she says.
© Solo dmg media
- On 27th April this article was amended to reflect that it was the Academy of Medical Royal Colleges and not the Academy of Medical Sciences that was involved in the research.
