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What Happens To The Body After Running A Marathon?

By Chidirim Ndeche 19 February 2018   |   5:00 am

Running a marathon is a physical and mental challenge. From losing a toenail to super hearing powers, runners undergo a number of changes, both painful and surprising, with trained marathoners staggering across the finish line with ravaged joints and shredded muscles.

So what does taking the body through such a gruesome exercise cause? This guide highlights the physiological effects the marathon body faces as it moves from one mile to the next.

Leg muscle damage
During a marathon, the feet suffer the bulk of the effects, leaving the leg muscles stressed, with cramps, sores, inflammation and microscopic tears. Months of training can cause so much trauma that runners’ toenails blacken and fall off. Tthe friction with socks and shoes can cause blisters. The blood vessels also take a pounding, haemoglobin levels dropping as low as 20 grams per litre of blood.

Shorter and lighter
Marathoners cross the line two centimetres shorter and 2-5kg lighter on average than when they began. Thankfully, this shrinkage, caused by loss of fluid in the body, is only temporary. Height is fully restored when fluid levels are replaced after a day or so.

As you run a marathon, so does your nose. Many people get serious sniffles while running for long periods outdoors due to exercise-induced rhinitis, probably caused by the increased air-flow inhaled as breathing rate quickens, sending the nose into mucus-producing overdrive.

Weight loss and dehydration
Of course, burning all that energy during a marathon will lead your body to burn calories, but not as many as you think. During the race, the body feeds on the glycogen it stores as fuel. It also causes the body to lose a lot of water, making it important to stay hydrated.

The heart and lungs work in tandem to supply more oxygen-rich blood to the working muscles and may get a little fatigued in the process. The kidneys may also suffer short-term injury due to a change in body temperature, decreased blood flow to the kidneys and dehydration. There may not be any long-term ill effects on the organs of marathoners, but it could be a more pressing problem for those at risk of heart-complications, with weakened organs or the elderly.

Immune system
The body focuses all its resources on keeping things moving, compromising the immune systems of marathoners. They may come down with colds and fevers after a race. Blood flow to the muscles and away from the digestive system may also slow down its functions, leading to abdominal pain, diarrhoea and bloat. Strengthen the immune system by eating healthy, nutrient-rich foods.

Many of the side effects of running a marathon are negative, but some positive effects can occur in the brain. It releases neurotransmitters that can produce feelings of euphoria and can distract or numb some of the physical pain from running.

Regardless of all these effects, thousands of people around the world run marathons annually with no long-term ill effects. The benefits of running a marathon include you ending up healthier afterwards. The real danger is taking on too much too soon, which is why most training plans emphasise a long, slow build-up to serious workouts. Our bodies wonderfully adapt to extreme situations, as long as we give them time.

Trust us, the feeling of accomplishment when you pass that finish line will outweigh any pain you experience.

In this article:
BodyChidirim NdecheMarathon