Heaviness in the legs while running can range from mild to debilitating. It can be caused by a variety of factors, conditions and training errors. Leg heaviness can be frustrating and prevent you from finishing your running routine. It is important to understand how it can develop during running and how you can alleviate and avoid it.
Running-related leg heaviness can occur if your legs become fatigued from excessive running, not taking breaks as needed, running on hard surfaces or by wearing improper footwear. Intense running can increase the amount of lactic acid in your body, which can lead to leg fatigue and tiredness. Leg heaviness can also develop if you do frequent hill work or sprint often. Trauma and damage to the muscles in the legs, such as sprains or strains, can also trigger leg heaviness while running. It can also develop due to medical conditions such as shin splints, tendinitis and compartment syndrome.
Take a break and sit down as soon as you notice symptoms developing. Place an ice pack or ice cubes wrapped in a towel against your legs to help ease any inflammation, swelling or pain. You can also apply a warming device such as a heating pad or blanket to your legs to quickly relieve symptoms. Wrap your legs with an elastic bandage or prescription stockings and elevate them to help decrease blood flow to the legs and ease heaviness and swelling.
To prevent running-related leg heaviness from reoccurring, consider wearing cushioned inserts in your running shoes to support your feet and lessen the impact when running on hard surfaces. Stretch out your legs and warm up prior to running to increase the blood flow in your legs and make the muscles more pliable. Do exercises to strengthen your abdominal muscles, which can help ease strain on your back and reduce leg heaviness and pain.
Contact a doctor if you can't lift your feet at all or begin to drag your feet while you run or walk. These could be symptoms of a more serious medical condition such as nerve or muscle damage, multiple sclerosis or amyotrophic lateral sclerosis. A doctor can provide a brace or ankle splint, physical therapy exercises, surgery or electrical nerve stimulation to help if leg heaviness is chronic or severe.