It’s great that you like to work out! If your body is shaking after your workout, it may mean you are experiencing muscle fatigue (aka your muscles are tired). During exercise, the fibers in a person’s muscles contract and relax, which allows the body to move. When a person is tired, some of those muscle fibers will continue to contract and others will start to relax, and this imbalance can lead to shaking or trembling. Another reason why your muscles might be shaking is from low blood sugar. Your muscles need enough glucose (a sugar found in carbohydrates) to be able to function at their best during exercise. If you skipped a meal or didn’t eat a pre-workout snack, your muscles will not be well-fueled at the start of exercise. By the end of your workout, the shaking you feel may be a sign of hypoglycemia, also known as low blood sugar. To prevent this, it is important to eat carbohydrates before and after your workout. Pre-workout, you should aim to have a small amount of carbohydrates, such as crackers, pretzels or a banana, so that your muscles have enough energy to begin exercising. After your workout, you should aim to have a snack or meal that contains both carbohydrates and some protein to repair those hardworking muscles! Another reason you may be experiencing shaking muscles is because you are dehydrated. When a person is dehydrated, their body will feel tired faster. To prevent this, make sure you are drinking enough water before, during, and after you exercise. Hydration needs vary depending how much you sweat and your age, but general rule of thumb is to aim for 7-10 ounces, 20-30 minutes before exercising, 4-8 ounces every 20 minutes during exercise, and 8-10 ounces within 30 minutes after exercising. It is also important to drink enough water throughout the day, not just around the time of your workout. If you are working out very hard for a long time or in the heat, it may be helpful to drink a liquid that also contains electrolytes, which are minerals that help balance the amount of water in your body. If you continue to feel your body shaking after exercise, make an appointment with your health care provider.
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