Inflamed tendons can be caused by a sudden injury, but they're usually triggered by small, repetitive movements over the course of many days, weeks or months. Repetitive motions put stress on the tendons, which creates micro-tears and localized inflammation. Identify what action is creating the problem and either take a break from it (at least a few days) or modify the movement somehow. If the tendonitis is work related, then talk to your employer about temporarily switching to a different activity. If your problem is exercise related, then you may be working out too aggressively or with improper form — consult with a personal trainer.  Playing too much tennis and golf are common causes of elbow joint tendinitis, thus the terms "tennis elbow" and "golfer's elbow." Acute tendonitis will usually heal itself if you give your body a chance to rest, but if you don't, it can become a chronic (ongoing) problem that's much more difficult to treat. The pain from tendonitis is primarily due to inflammation, which is an attempt by the body to heal and protect the injured tissue. However, the body's inflammatory response is usually too much and actually contributes to the problem, so controlling it is key to reducing the symptoms. As such, apply an icepack, frozen gel pack or bag or even a bag of frozen veggies to your inflamed tendon in order to reduce inflammation and dull the pain. Apply cold therapy every few hours until the pain and inflammation subside.  If the inflammation is in smaller, more exposed tendons/muscles (such as the wrist or elbow), then apply the ice for about 10 minutes. If it's a larger or deeper tendon/muscle (such as the shoulder or hip), then leave the ice on for closer to 20 minutes. While you're icing the inflamed tendon, elevate the area and compress it by tying a Tensor or Ace bandage around the area — both techniques more efficiently combat inflammation. Don't forget to wrap ice up in a thin cloth before your apply it, as it will prevent negative reactions such as ice burn or frostbite....

TL;DR in Vietnamese:
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