Exercise and Athletics With Sickle Cell Disease

Regular exercise is healthy for everyone, including people with sickle cell disease (SCD). However, people with SCD should keep exercises mild and make sure to take breaks. Strenuous activities can trigger pain crises and other complications of SCD.

People with sickle cell trait do not have sickled red blood cells and are generally healthy. However, intense exercise can turn sickle cell trait into a disease with severe complications. Athletes with sickle cell trait should be careful to stay hydrated, take breaks, and stay cool during strenuous activities.

How much exercise is safe for people with sickle cell disease?

Intense exercise can trigger complications of SCD because it increases blood flow. Some doctors have advised some people to avoid exercise altogether. However, mild exercise is generally safe and helpful for people with SCD.¹

People with SCD usually have fewer blood vessels in their muscle tissue, which prevents oxygen delivery. Moderate exercise can help people with SCD form new blood vessels in the muscle. This helps improve blood and oxygen delivery.²

In people with SCD, mild exercise also improves:^1,2

• Muscle function
• Overall physical ability
• Sleep quality
• Concentration
• Social interactions

Larger clinical trials are underway to determine how mild exercise can be used as a therapy in SCD.

What types of exercises are safe and healthy?

Low-intensity aerobic exercises are the best options for people with SCD. These are exercises where your heart beats faster and you use more oxygen than normal. However, it is important to pace yourself, take breaks, and avoid intense activities. If you feel breathless, nauseous, or weak, the intensity is too high. Remember to stay hydrated.³

Some examples of low-intensity exercises you can do include:⁴

• Brisk walking or hiking
• Biking outside or in a spin class
• Dance fitness, such as Zumba
• Rowing
• Swimming

Include warm-up, cool-down, and stretching portions of your exercise routine. These are not all the exercise options, and not all of these options are right for everyone. Talk to your doctor to discuss how to make mild exercise part of your lifestyle.

What are the concerns for athletes with sickle cell trait?

People with sickle cell trait have only 1 copy of the abnormal sickle hemoglobin gene. They can pass on the gene to their children, but are otherwise healthy and do not have a disease. However, people with sickle cell trait can experience heat stroke and muscle breakdown (rhabdomyolysis) during intense exercise. This can be fatal if untreated.^5,6

Normally, 1 copy of sickle hemoglobin is not enough to cause red blood cells to sickle, but with intense exercise, it can be enough. This is sometimes called “exertional sickling.” Exertional sickling is responsible for 5 percent of sudden sports deaths in student athletes over the past decade. People with sickle cell trait are 30 times more likely to die during basic military training.^7-9

The risk of this happening can be reduced by avoiding dehydration and extreme temperatures. Athletes should not be disqualified because they have sickle cell trait. However, athletes with sickle cell trait should be careful when participating in competitive sports or training activities. To prevent illness, it is important to:^5,6,10

• Set your own pace and build intensity slowly
• Rest often in between sets and drills
• Drink plenty of water before, during, and after exercise
• Keep your body temperature cool in hot temperatures
• Stop activities if you feel cramping, pain, swelling, weakness, breathlessness
• Control asthma
• Create an environment where athletes with sickle cell trait can report symptoms immediately
• Seek medical care immediately when feeling ill

Universal screening is done at birth, but many athletes may not know their sickle cell trait status. Many institutions use screening strategies to identify athletes with sickle cell trait. Screening, precautions, and education for coaches can help save lives.