Finishing a marathon is seen as the ultimate challenge by many runners, but pounding the pavement for 26.2 miles can take its toll on the body. And that’s not to mention training.
Ahead of the London marathon, we found out how long distance running really affects your body and whether there’s any truth behind the claims.
Impact On Joints
It’s a myth that running is bad for your joints, according to Bupa clinical fellow, Jemma Batte.
“Joints help to absorb shock and smooth movements between bones that meet within a joint, so movement is friction-free. This means that the joints in our legs and feet help to ease the impact on our body when running,” she tells The Huffington Post UK.
“Whilst injury is a risk of running, there is no evidence that those runners are any more likely to develop arthritis than those who don’t.”
Pain to the front of the knee and underneath the kneecap, known as Patellofemoral Pain Syndrome (PFPS) or “runner’s knee” is the most common injury reported by marathon runners.
The NHS says it’s not clear why some runners experience PFPS, but it’s thought to be linked to muscle weakness or your kneecap being slightly out of place.
Thankfully, PFPS can be prevented with the right exercises.
Bupa’s senior physiotherapist Lisa Reid says: “Try to avoid running on hard surfaces and be careful not to increase your mileage and hill runs too much in the lead up to the marathon,.”
“Strengthening your quadriceps and glutes and stretching your hamstrings can also help prevent runner’s knee.”
Contrary to popular belief, sports therapist Jamie Webb adds that “running is actually good for your joints”.
“The latest research suggests it actually improves cartilage health rather than damaging it,” he says.
“It is normally the muscles’ effect on the joints that give us pain in the joints, not the joints themselves. Running keeps the joints sliding and gliding as they were intended and keeps us moving.”
Long distance running may cause you to experience pain along your shin bone (tibia), known as “shin splints”, as this usually develops or gets worse during intense exercise.
Reid says: “It’s caused by your muscles, tendons or bone tissue around your shin becoming irritated and is commonly caused by over doing it.”
“Fatigue pain will go down after 48 hours, but if the shin tissue is injured, pain will come back again when you start to run.”
You can avoid shin splints by wearing the correct running shoes and strengthening and stretching your calves.
Shin splints are usually temporary and Webb says that overall “running is an excellent way to improve your bone health”.
“The impact of your body weight on the ground stimulates more bone to be produced to make the bones stronger to deal with the impact,” he says.
“If you don’t do impact sports, the bones get weaker. This is why elite cyclists are prone to osteoporosis.”
According to June Davison, a senior cardiac nurse at The British Heart Foundation (BHF), running for any distance can be beneficial to the heart.
“When you do any kind of aerobic exercise the heart rate increases, because when adrenaline is released it causes your heart to beat faster,” she says.
“Coupled with that, because the heart is beating faster, you’re actually improving the oxygenation to the heart and helping to strengthen the heart muscle.”
Despite what some newspapers may lead you to believe, Davison says in most cases, long distance running will not put excessive strain on the heart or cause heart attack.
“It’s something that often hits the headlines so it might seem like it’s more common than it is,” she says.
“Relatively speaking the numbers are quite low, but we do know that if you have some underlying coronary heart disease in your arteries then exercise or experiencing any kind of emotional distress, can, in some instances, trigger a heart attack.
“So it’s not necessarily the running...it’s likely that it would have happened anyway.”
BHF urges people to “be safe” about long distance running and advises building up your distance gradually.
When you run, the lungs bring oxygen into the body that the heart then pumps to muscles for energy. The lungs also remove carbon dioxide, which is created as a waste product when you produce energy.
When you run long distance, you need more energy, meaning your body uses more oxygen and produces more carbon dioxide. As a result your lungs have to work harder.
The European Lung Foundation explains: “To cope with this extra demand, your breathing has to increase from about 15 times a minute (12 litres of air) when you are resting, up to about 40–60 times a minute (100 litres of air) during exercise.
“Your circulation also speeds up to take the oxygen to the muscles so that they can keep moving. When your lungs are healthy, you keep a large breathing reserve. You may feel ‘out of breath’ after exercise, but you will not be ‘short of breath’.
“When you have reduced lung function, you may use a large part of your breathing reserve. This may make you feel ‘out of breath’, which can be an unpleasant feeling, but it is not generally dangerous.”
Debbie Roots, cardiorespiratory nurse consultant and medical adviser for the British Lung Foundation, adds that both healthy people and those with lung conditions can experience a better quality of life when they exercise.
“Long distance running can help to improve your muscle strength, so you can use the oxygen you breathe more efficiently. It can also improve your general fitness, and help you to cope better with feeling out of breath,” she says.
“Overall, long distance running, following a carefully planned training programme, can help you to feel stronger and fitter.”
During intense exercise your muscles break down glucose (an energy supply) without as much oxygen available and this forms lactic acid.
Batte says this build up of lactic acid can cause your muscles to feel fatigued and sore.
“It’s a common misconception that the effects of lactic acid build-up can be felt for days, but this isn’t the case,” she explains.
“Ongoing soreness days after a marathon is actually caused by tiny muscle tears and inflammation.”
To reduce soreness days after the marathon, Batte recommends going for a cold bath with ice if possible.
“You only need to be in it for a couple of minutes to reduce the inflammation. Some people recommend alternating cold and warm water in the shower, which causes the blood vessels initially to constrict with the cold water, and then dilate with the hot/warm water to increase the numbers of oxygen-carrying blood cells to your muscles,” she says.
“Gentle movements can help to ease some of the muscle pain in the first 24 hours after the race. Rest, rehydration and carbohydrate and protein replacement will also help the body to recover.”
Unsurprisingly, running 26.2 miles is likely to make your body experience tiredness.
Dehydration or lack of fuel can lead to your body shutting down, but Batte says this is “only in extreme cases”.
“Your body will give you some warning signs, however it’s important to replenish your fluids before you reach this stage,” she says.
“If you’re feeling faint or weak, or if you feel ‘empty’, replenish your fuel supplies by having some water and energy producing foods such as carbohydrates or protein.”
Dr Seth Rankin, founder of London Doctors Clinic, says this has a knock-on effect on your immune system.
“There is much evidence that the exhaustion caused by running a marathon temporarily weakens your immune system for up to three days,” he says.
“Infections are more common so try to avoid being coughed over for a few days until you have time to recover.”
You’ll often see runners overwhelmed with emotion when they finish a marathon and it’s not just because they’re relieved to have made it to the finish line.
Batte explains: “When you exercise, your body releases chemicals called endorphins.
“These endorphins make you feel happy and trigger positive energy throughout your body, regardless of how long or short your burst of exercise was.”
She adds that some runners report experiencing the ‘post marathon blues’, although this is not clinically proven.
“After changing your lifestyle and meeting your target, life can feel a bit flat,” she says.
“To avoid this, plan your next goal to keep you motivated.”