CRAMPS, SPASMS, AND SIDE-STITCHES
A muscle cramp is a tight, suddenly contracted muscle that is over-facilitated. It usually occurs during activity, but waking in the middle of the night with foot or leg cramps is not uncommon. The exact cause of muscle cramps is often not fully known and may be very individual (one person’s cramp may be caused by something different than another’s cramp). A muscle cramp usually involves a single muscle or group of muscles. Possible causes might include dehydration, low levels of sodium or magnesium, an overworked muscle, or side effects from a prescription drug. Muscle cramps generally last a relatively short time (unless you’re having a bad one like a calf cramp in the middle of a bike ride; then it feels like a long time). The terms “muscle cramps” and “spasms” are often used interchangeably as their definitions are somewhat scant. True muscle spasms occur most often in people with neurological diseases such as multiple sclerosis and cerebral palsy and those with severe spinal cord injury.
Side-stitches refer to pain typically in the side of the upper intestinal area; these usually occur during running. They may be directly or indirectly related to either the skeletal muscles such as the abdominals or the smooth muscle of the intestines.
Side-stitches are also not well understood by physiologists but they often appear to originate from the diaphragm or the intestines, and usually just after fluid or other food is consumed. They can not only be painful but also reduce your physical activity, often causing you to slow or stop during competition. Bending forward while tightening abdominal muscles or breathing through pursed lips with increased lung volume can help reduce these painful stitches. During activity, the most success I’ve seen is with deep breathing associated with a specific foot strike, swim stroke, or pedaling cadence. For example, while running, breathe in during three foot strikes (right, left, right) and out during the following four foot strikes (left, right, left, right). During faster running, inhaling on two and exhaling on three foot strikes is effective.