If you've finished an especially intense workout, you may ask yourself, "Why do my legs ache after exercising?" Your question is a valid one which can point to several causes. It is one of the paradoxes about physical fitness that sometimes exercising can cause pain despite the fact that it is essential for good health.
Why Do My Legs Ache After Exercising?
Lack of Activity
Achy leg muscles can be a result of inactivity. Perhaps you have not been exercising frequently. Suddenly, your body is faced with a rush of new activity when you decide to take up jogging or biking. Unconditioned muscles are likely to ache after a surge of new activity. The irony of your aches and pains is that you must exercise in order to prevent future issues. However, with some people, the initial pain can be a barrier to continued exercise.
On the other hand, if you do exercise, it is important that you stretch before and after your workouts. Your hips muscles may become tight if you hike or bike, causing that uncomfortable ache in your legs. Stretching helps increase your flexibility and range of motion which can help prevent the pain caused by exercise. Stretching after exercise takes advantage of your warmed muscles and the increased blood flow to achieve the maximum benefits.
Lactic Acid Build-Up
If you exercise regularly, you build up your lung capacity and improve your body's ability to deliver oxygen to your body's tissues. The glucose in your blood will fuel your activity. If you cannot keep up with your energy demands, your body will resort to breaking down carbohydrates for energy using a method which does not require oxygen, producing lactic acid in the process.
The result of this lactic acid build-up is pain in your legs, often as a burning sensation. In a way, this action is one safeguard your body uses to encourage you to reduce the intensity of your activity. Contrary to popular belief, lactic acid build-up causes pain during and immediately after exercise. It is not the cause for the achiness you feel later, according to a 2006 paper published in Scientific American.
Sometimes muscle strain may occur a day or two after you have worked out. Delayed onset muscle soreness (DOMS) is common when you begin a new exercise program. If you wonder, "why do my legs ache after exercising," the pain represents your body making the adjustment to your new activity.
The exact cause, and thus cure, of DOMS is not known. Researchers believe that this pain may be caused by tiny tears in your muscle fibers which occur when you exercise, especially after an intense effort. While you may associate it as a beginner's problem, even seasoned athletes can experience DOMS.
The important thing is to not let minor muscle aches keep you from exercising. Gentle activity such as walking or yoga can help relieve your pain by ensuring the continued flow of oxygen and energy to your muscles. This can help speed the recovery of your muscles and thus your return to exercise. It's simply a matter of helping your body to heal itself.
Another possible cause of post-exercise pain can be shin splints. With shin splints, your pain is typically confined to the tibialis anterior muscle on the front of your lower leg. Like other causes, shin splints occur from overuse of your muscles.
Whereas with muscle strains you use low intensity activity to work through the pain, with shin splints you should rest and refrain from exercise until your pain abates. Alternating ice and heat therapies may provide some relief. Rest, in most cases, is the best cure.
Learn from Experience
Leg pain after exercise can be very frustrating, especially if you are just beginning a new workout program. Recognizing the possible causes can help you avoid the aches which may keep you from exercising. Learn from your experiences so that you can stay active.