My knees suddenly feel weak when I walk. What’s going on?

In life, many people will bend their knees and feel weak in their legs when walking, and they want to run. This phenomenon is commonly known as "weak legs".

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Many people always tend to think that it is caused by calcium deficiency, especially the elderly.

Calcium deficiency can indeed cause leg muscle weakness, but there are many different situations. In addition to calcium deficiency, weak legs may also be a warning signal of disease.

1. Sudden weakness in the knees? It may be a warning of 5 diseases

The knee joint is the most complex and largest joint in the human body, primarily responsible for movement and bearing body weight, but it is one of the most vulnerable joints in the body.

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Some bad habits in life, such as sitting or standing for long periods of time, excessive exercise, crossing your legs, improper exercise, etc., may cause wear and tear on it.

In addition, sudden weakness in the knees may be a signal of the following diseases besides calcium deficiency.

01

Meniscus injury

The meniscus is two fibrous cartilage plates between the articular surfaces of the femur and tibia, which have the functions of reducing shock, lubricating the joints, and absorbing heat.

When the meniscus is injured, symptoms such as joint pain, swelling, and fluid accumulation will appear. If the injury continues, the legs may become weak and the joints may become stuck.

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People who often play basketball or engage in strenuous exercise have a higher risk of meniscus injury.

02

Bone hyperplasia

As we age, bone hyperplasia, which we often call bone spurs, is more likely to occur in the joints.

Bone spurs generally do not cause obvious symptoms in the early stages. As the disease progresses, the bone spurs will fall off and form loose bodies. When they happen to migrate to the joint space, they can easily cause symptoms of joint pain and spasm of surrounding tissues. This disease is relatively common in middle-aged and elderly women.

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03

Synovitis

Many middle-aged and elderly people like to walk, climb mountains, squat and do exercises, but these exercises will cause repeated friction of the knee joint, which can easily cause congestion and hypertrophy of the joint capsule, and then cause synovitis.

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The specific symptoms are knee pain, swelling and fluid accumulation, and the symptoms will recur. In the later stages, the knee joints will feel increasingly weak and normal activities may be restricted.

04

Chondromalacia patella

As we age, the patella in our body may degenerate, making it easier for us to experience weak legs when walking.

05

Cerebral infarction

Cerebral infarction can cause obstruction of blood circulation in the brain, and the brain's ability to control the limbs will decrease. The legs at the end of the body are more easily affected, and there may be symptoms of imbalance and weak knees when walking.

2. Who has worse knees, people who run regularly or people who sit for a long time?

There is no doubt that exercise is good for health, but many people are afraid of excessive wear and tear on their knees during exercise and are undecided about whether to exercise or not. So should we exercise?

In 2017, a study published in the authoritative American medical journal "Journal of Orthopedics and Sports Physical Therapy" showed that sitting for a long time is more harmful to the knees than running.

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The study conducted a meta-analysis of 17 studies involving more than 114,800 people. The results showed that the incidence of arthritis in competitive runners was 13.3%, the incidence in sedentary people was 10.2%, and the incidence of arthritis in people who ran for fitness was only 3.5%.

In this regard, researchers believe that excessive fitness running may induce joint problems, but ordinary fitness running is good for joint health.

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Sitting for long periods of time will cause disorders in the normal nutritional metabolism of the knee joint cartilage. A large amount of metabolic waste cannot be discharged in time, making it impossible for the cartilage to absorb nutrients and oxygen in time, which can easily cause functional disorders.

3. 5 behaviors that are "torturing" your knees, correct them as soon as possible

Wear and tear of the knee joints is related to a variety of daily behaviors. If you are still doing these things, you must correct them as soon as possible.

01

Sudden intense exercise without warming up

Not warming up before exercise, especially for people who have no exercise habits, will put tremendous pressure on the knee joints, and the risk of injury will increase exponentially.

Exercise must be gradual and done according to one's ability, and you must warm up thoroughly before exercising.

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02

Sitting for a long time and crossing legs

Sitting for a long time will slow down the metabolism and blood circulation in the knee joint. If the knee joint does not get enough activity for a long time, its function is prone to decline.

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Crossing your legs will also invisibly increase the pressure on the knee joints and increase the wear of the articular cartilage.

03

Weighted stair and hill climbing

The knee joints already have to bear a lot of pressure when climbing stairs and mountains. Adding weight will undoubtedly make things worse and increase the risk of joint injury.

04

Often skipping rope on concrete floor

The concrete floor cannot cushion the impact when you land, and will put greater pressure on the knee joints.

When jumping rope, it is best to choose a plastic track, or jump on a mat, which is helpful in relieving pressure on the knees.

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05

Wearing high heels for a long time

Studies have found that when wearing high heels and going up and down stairs, the pressure on the knee joints is 7 to 9 times the body weight, and wearing high heels will promote the softening of women's knee joints and increase the probability of knee injuries.

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The knee joint is very important to our health. Once it suffers functional damage, normal activities may be affected. Therefore, we must protect the knee joint more in daily life and correct the above-mentioned bad habits in time.