Runners may experience a variety of cramps and muscle injuries, but running can also lead to flank pain, which occurs on your side, between your ribs and hip. It may be confused with abdominal or back pain, but it's often related to problems in the urinary system, especially kidney infections. Applying ice, massage or stretching won't resolve flank pain that is due to urological causes, even if muscle spasms accompany the pain. The causes of flank pain range from non-threatening and temporary to serious and life-threatening, so it's important to see a doctor.
Causes of Flank Pain
Flank pain often means kidney problems, MedlinePlus says, although disk disease, muscle spasms, shingles and spinal arthritis may also be at its root. Kidney problems that trigger flank pain range from kidney infections or kidney stones to kidney abscesses or kidney disease. Although pain may be experienced generally through the abdomen and back, a tap over the kidney area can bring the true source of the pain to light.
Hematuria
Hematuria refers to blood in the urine and can accompany flank pain in runners. "Jogger's hematuria" is thought to occur because of repeated jarring of the bladder. Running on an empty bladder can increase the risk of hematuria because there is no fluid cushion between the base and the wall of the bladder. Bladder infections are less likely to cause flank pain than kidney infections, MayoClinic.com says, but hematuria can occur due to problems anywhere along the urinary tract. Hematuria can occur with any strenuous exercise, but runners are most commonly afflicted. Bladder trauma and dehydration are suspected reasons, as well as red blood cell breakdown from prolonged aerobic activity.
Accompanying Symptoms
Other symptoms can accompany flank pain other than hematuria. Problems with urination, from hesitancy and decreased flow to painful urination or increased urgency, may accompany flank pain. Abdominal pain, chills, fever, nausea and vomiting are also symptoms of kidney infection or other urological problems. You may have a serious problem even if you don't experience these other symptoms.
Treatment
Hematuria due to "jogger's bladder" or "runner's bladder" may resolve with 24 to 48 hours of rest. When hematuria is due to running, it usually resolves within one to two days, but you should always have flank pain checked out by a doctor, who can determine if your flank pain is caused by muscle spasms and prescribe anti-inflammatory drugs or physical therapy. A kidney infection will require antibiotics and you may require hospitalization for a serious infection or a serious case of kidney stones.
References
- MedlinePlus: Flank Pain
- MayoClinic.com; Blood in Urine (Hematuria); September 2009
- Dr. RajMD.com; Hematuria; Dr. Eugene Rajaratnam
- "Fundamentals of Sports Injury Management"; Marcia K. Anderson; 2002
- San Diego Running Institute; Lower Back Pain or Kidney Infection?; Dr. Victor J. Runco
- Lake Charles Urology: Hematuria
