Maybe you were fortunate enough to have watched the 1983 NYC Marathon on TV when, in an incredibly exciting finish, New Zealand’s Rod Dixon passed England’s Geoff Smith at the 26-mile mark. If you did, perhaps you’ll recall seeing Dixon, as he stalked Smith up the length of First Avenue, periodically reaching back with his left hand to massage his thigh.
During the post-race interview Dixon was asked about it and explained (… and you’ll have to supply the Kiwi accent here…): “My hamstring was beginning to tighten up a bit. I had to work on the trigger point to relax it.”
I’m going to venture that most viewers didn’t quite understand the reference. The trigger point? What is that, and how does “working on it” get a muscle to relax?
Trigger point (TP) is a term popularized by the late Dr. Janet Travell, who co-authored the “bible” on the subject. Dr. Travell, who was President Kennedy’s personal physician and who specialized in the treatment of musculoskeletal pain disorders, described trigger points as “areas of hyperirritability within a taut band of muscle that is symptomatic with respect to pain; it refers a pattern of pain at rest and/or on motion that is specific to that muscle.” She believed these areas usually developed as a result of acute overload, overwork fatigue, direct trauma or chilling. An “active” trigger point, she said, is always tender, prevents full lengthening of the muscle, and usually refers pain on direct compression. (Referred pain, of course, means just what it says: the area of perceived discomfort is some distance from the source of the discomfort.)
The highlighted terms above are the significant ones when describing the relationship between running and TPs, as Rod Dixon found out somewhere around mile 18. Many of the vague, nagging pain syndromes common to runners can be traced to the gradual development of TPs as a result of overwork or overuse injuries. Travell felt that the taut bands found upon palpation of affected muscles were due to either contracture of muscle fibers or scarring of connective tissue surrounding the muscle fibers. Both would be the result of microtears in the tissues from overuse. Subsequent “activation” of the TP would cause pain and tightening of the whole muscle, making it difficult to easily move through the normal range.
This is what Dixon was experiencing on First Avenue, and it also describes what I think many runners commonly claim to be “sciatica.” A review of Travell’s illustrations of referred pain patterns clearly reveals several muscles with TP distribution areas closely resembling the posterior buttock, thigh and leg pain which could easily be mistaken for a nerve irritation. Some of these muscles are the gluteus minimus and piriformis in the buttock and the lateral hamstrings in the thigh. And, although it is not shown as such in Travell’s illustrations, I have also seen several patients with TPs in the lateral calf muscles that refer pain proximally (toward the trunk), with a similar mimicking of sciatica.
TPs are generally easy to find. They do feel like a small nodule of hardened tissue as compared to the rest of the muscle belly, or a thin band that feels like a bass string. Compression of either will cause the subject to experience immediate pain; prolonged compression often causes the referred pain. (Since TPs can also affect the autonomic nervous system, “pins and needles” can also be felt on occasion, which helps explain the misinterpretation of the problem as a “pinched nerve.”)
Travell’s recommended treatment of TPs consists of passive stretching of the muscle, but the catch is that a muscle with an active TP cannot be effectively stretched until the TP is de-activated. There are several ways to do this. The one most applicable to oneself is known as “ischemic compression,” whereby direct pressure via a fingertip or knuckle is increasingly applied for 30-60 seconds into the TP area. This blocks the blood flow (ischemia) to the TP, cause it to “relax.” When you release the pressure, blood surges through the area which helps to both remove waste products and promote healing of the tissue. (Don’t forget to immediately perform a gently stretch to the muscle for 60-90 seconds.) Essentially, this is what Rod Dixon was doing to his hamstring to get himself through the remainder of the race.
If you have a chronic, difficult-to-define problem, try poking around the muscles of your buttock and leg. If you find a sensitive area or two, give the compression treatment/stretch a try 2-3 times per day. Don’t torture yourself as you press (leave that to the professionals); just work into it as you would mold clay.