After working out, most people expect to feel soreness or fatigue, although experiencing a sensation of numbness and tingling in your left arm is not uncommon. Most of the time, the numbness and tingling results from behavior related to your workout.
Sometimes, serious medical conditions also cause these symptoms. Fortunately, most cases of numbness and tingling in your arms and hands after exercise are preventable and treatable with changes in your workout and prompt medical care.
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Arm Numbness After Working Out
Injury or excess pressure on a nerve in your neck or left arm is a common cause of arm tingling or numbness after working out. Repetitive exercises such as lifting weights or holding the same position for a long period of time puts pressure on your nerves and decreases the blood flow to the area, leading to numbness and tingling.
According to Harvard Health Publishing, a deficiency in vitamin B12 can also lead to numbness or tingling in your arms. It can also occur in your arms, legs or feet. This problem can typically be easily treated by eating more foods that contain B12 or by taking a supplement.
Medical Causes of Numbness
Numbness and tingling in your left arm after you exercise sometimes results from a medical condition that affects the nerves in and around your arm. Diabetes interferes with the flow of blood to your extremities, leading to numbness or tingling. Hypothyroidism can also cause tingling in your arm when lifting weights due to decreased blood flow, especially after you expend energy during a workout.
Cardiovascular problems such as heart attack, stroke, transient ischemic attack and atherosclerosis also diminish blood supply to parts of your body, leading to numbness or tingling. If your numbness or tingling is accompanied by difficulty speaking or understanding speech, confusion, dizziness or droopiness on one side of your face, dial 9-1-1 or your local emergency number, as these are symptoms of stroke, which is a life-threatening condition.
Treating Arm Numbness
Changes to your workout routine, such as alternating exercises or taking breaks during strenuous workouts, are often enough to treat numbness and tingling in your arms and hands after exercise. If your numbness results from a vitamin or mineral deficiency, taking a supplement treats the deficiency; however, check with your doctor before taking any supplement.
Treatment of arm numbness after working out due to diabetes requires careful management of diet and exercise. You may require medication if dietary changes are insufficient. Numbness in your left arm that results from cardiovascular problems such as stroke requires emergency treatment, including medications and surgery along with follow-up to prevent worsening or complications.
Read more: Causes of Finger Numbness
Tips for Prevention
Eating a balanced diet helps prevent numbness due to vitamin and mineral deficiencies as well as cardiovascular problems. Controlling your blood sugar and taking medication as prescribed helps prevent numbness related to diabetes. Working with a trainer to learn proper form and technique helps prevent repetitive stress injuries that cause numbness and tingling and also helps protect you against further injury that can result when your arm is numb.