Calf pain occurring with walking can often be mistaken for muscle pain when it could represent a more concerning condition. Intermittent claudication (IC) is described as lower extremity pain, usually beginning in the calf, triggered by exercise. Intermittent claudication is said to be a symptom of peripheral vascular disease, a disorder that is often associated with coronary artery disease (CAD). In the United States, the prevalence of IC in individuals over the age of 60 is 5% in men and 2.5% in women. Some of you may wonder why special attention would be given to calf pain when there are exisiting cardiac symptoms. Simply put, IC can be more functionally incapacitating than some of the symptoms associated with CAD, such as angina (i.e. chest pain) or shortness of breath.
So what causes this debilitating condition? Certainly, many of you have heard the term “atherlosclerosis”. For those who are unfamiliar with it, atherosclerosis is a process in which debris accumulates on the inside of an artery. This causes a decrease in space within the blood vessel, leading to decreased blood flow. If there is less blood flow, you can expect there to be less oxygen delivered to the working muscles during exercise, resulting in leg pain. This is why the classic presentation of IC includes pain with exercise and relief of symptoms at rest.
Treating intermittent claudication starts with targeting the causes of atherosclerosis, such as smoking, hypertension and hyperlipidemia. From a Physical Therapy (PT) perspective, exercise is the key to symptom alleviation, which sounds counterintuitive since exercise is what specifically causes the leg pain. This is why The American Heart Association and American College of Cardiology (AHA/ACC) have established recommendations with particular elements for an exercise program for people with IC. The 4 key elements are: 1. A supervised walking program in which light IC symptoms occur in 3-5 minutes at a certain walking intensity, 2. Walking until the leg pain is moderate, followed by a resting period until the symptoms disappear, 3. Repeat #2 for approximately 35 minutes, 4. At every session, increase the total time by 5 minutes up to 50 minutes, 3-5 times per week, for 12 or more weeks. The severity of the symptoms is coded according to the Claudication Pain Rating Scale. After completing a supervised walking program, your PT will be able to prescribe you a home walking program, which you can follow in the long term.
Although I have described an already outlined specific exercise regimen, you should not undertake any exercise program without consulting a Doctor or Physical Therapist, as they will take in consideration your goals, comorbidities, and the way you respond to exercise.
- Brunelle, C.L. and Mulgrew, J.A. (2011). Exercise for Intermittent Claudication. Physical Therapy, (91), 997-1002.
- Shammas N.W. (2007). Epidemiology, classification, and modifiable risk factors of peripheral arterial disease. Vascular Health Risk Management. (3), 229–234.