dont blindly chase running volume overtraining can damage your kidneys

Today is March 13th—World Kidney Day. Given the rising incidence of kidney disease and the general lack of public knowledge about its prevention and treatment, the International Society of Nephrology and the International Federation of Kidney Foundations have jointly proposed that the second Thursday of March each year be designated as World Kidney Day.

The importance of kidneys to our bodies is self-evident. In recent years, cases of kidney failure caused by excessive running have been increasing, becoming an issue that runners must pay attention to.Today, I'll explain why running can lead to kidney failure and how to avoid over-exercising.

————

Over-exercising leading to kidney failure is not uncommon

26-year-old Xiao Zhang works in a government office. After long hours of sitting, he felt discomfort all over his body. His colleagues and friends suggested he exercise after work, but Xiao Zhang procrastinated. He eventually set a high-intensity workout plan involving running and swimming.

One day after work, Xiao Zhang skipped dinner, changed into his sportswear, and ran for 40 minutes in his neighborhood, sweating profusely. After running, he went to the community pool and swam several laps. After this intense workout, Xiao Zhang was exhausted and collapsed on the ground. Initially proud of his exercise, he began to feel weak, sore, nauseous, and experienced a significant reduction in urine output two days later. His urine turned a strange coffee color, and a hospital check revealed he had rhabdomyolysis.

Rhabdomyolysis is related to excessive exercise, where muscle cells dissolve after overuse. When Xiao Zhang went to the hospital, his blood creatinine level was over 1000 umol/L, far above the normal value of 132 umol/L, indicating acute kidney injury. Mild kidney damage usually causes no obvious discomfort, but severe damage can lead to symptoms like nausea and vomiting.

Xiao Xia, an employee in Wuhan, jogged for three hours in a park. After returning home, she felt her legs were heavy and could only squat or sit with the help of her hands. The next day, she noticed her urine was soy sauce-colored and rushed to Hubei Provincial Hospital.

Due to her busy work schedule, Xiao Xia only exercised on weekends and holidays, engaging in 1-3 hour night runs every weekend. The low frequency but high intensity of her workouts violated the body's adaptation rules, leading to over-exercising.At the hospital, Xiao Xia was diagnosed with exercise-induced rhabdomyolysis and acute kidney failure. She underwent four hours of dialysis that day, and her condition gradually improved.

————

Why does running cause kidney failure?

Muscles are composed of muscle cells, and during excessive exercise, some muscle cells rupture, releasing a substance called myoglobin. This myoglobin seeps into the bloodstream, where its enzymes produce toxins, causing rhabdomyolysis. Myoglobin needs to be excreted through the kidneys, but because it is a large molecule, it can easily block the renal tubules, affecting kidney function.

If the condition is not severe, one may feel muscle soreness, fatigue, and reduced urine output. In severe cases, urine may turn red or black, or there may be no urine at all. Immediate hospital treatment is necessary to prevent kidney failure and other organ failures.

Rhabdomyolysis is not scary and is not difficult to treat. It does not involve large-scale muscle dissolution but rather muscle relaxation. The main danger is myoglobin blocking the renal tubules, leading to kidney failure. Timely fluid replacement to flush out myoglobin from the blood can effectively control the condition, and treating the underlying cause of muscle dissolution will improve the condition.

Not all cases of rhabdomyolysis lead to acute kidney failure. Exercise-induced acute kidney failure is relatively rare, with about 10% to 40% of patients developing acute kidney failure requiring dialysis.

————

So, how can you avoid over-exercising?

Running is an addictive sport, but increasing the volume excessively is dangerous. Avoiding over-training and reasonably planning your training schedule is crucial for every runner.

1. Tailor your training volume

The required training volume is highly individualized. This means you shouldn't compare yourself to others when planning your training. While a little competition can motivate you, remember that your goal is not to outdo others in training volume but to optimize your own training plan.

2. Pay attention to your physical condition

People often believe they are as strong as they were in their youth and think that maintaining a high exercise volume is possible with persistence. In reality, skipping workouts occasionally won't significantly impact your youthful fitness. The key is to realistically assess your current physical condition and plan your training accordingly.

3. Adjust your plan as needed

Physical conditions can change unpredictably. Even if your training plan is customized, you should frequently monitor your body's condition. If you find the current training unbearable, feel injured, or excessively fatigued, it's time to adjust your plan or take a break.

4. Pay attention to body signals

Familiarizing yourself with your body's symptoms can help avoid over-training. Common signs include heavy legs, prolonged recovery between workouts, or deteriorating physical condition despite hard training. Frequent injuries also suggest over-training.

5. Enhance nutritional intake

Ensuring adequate nutrition is essential for your body to handle exercise. Avoid malnutrition—losing weight through exercise is possible, but it should be a gradual process. Do not drastically reduce calorie intake. Ensure sufficient carbohydrate and protein intake for post-exercise recovery.

6. Ensure rest time

Adequate rest is crucial. Ensure at least one rest day per week. If you want to relax more, take a week off each month, keeping exercise volume below 60% of normal. Sufficient sleep is also important, especially after high-intensity workouts.