Given how hard you’ve been training, it’s possible that your muscles are quite sore after each workout, perhaps remaining that way for several days postexercise. If so, there are some things you should know about this condition, generally referred to as delayed-onset muscle soreness (DOMS).
Contrary to popular belief, DOMS is totally unrelated to a buildup of lactic acid. Lactate is rapidly cleared from muscles following a workout. Within an hour or two postexercise, it is either completely oxidized or taken up (via the Cori cycle) and utilized for glycogen resynthesis. Since DOMS doesn’t occur until at least 24 hours after a training session, it therefore follows that lactic acid cannot play a part in its cause.
Although the exact mechanisms are not fully understood, current theory suggests that DOMS is actually a product of damage to muscle tissue. It is fundamentally caused by eccentric exercise, where muscles are lengthening under extreme tension. Here is the proposed model: During eccentric activity, the contractile elements (actin and myosin) of working muscles exert a “braking” action in order to resist the forces of gravity. This produces small microtears in both the contractile elements and surface membrane (sarcolemma) of the associated muscle fibers. These microtears allow calcium to escape from the muscles, disrupting their intracellular balance and causing further injury to the fibers. Various proteins (such as neutrophils and macrophages) then interact with the free nerve endings surrounding the damaged fibers, resulting in localized pain and stiffness.
Despite the associated discomfort, DOMS is often regarded as a necessary part of exercise. For many, being sore creates the feeling that something is “happening” to their body—that they really accomplished something during their workout. And, on the surface, DOMS would seem to play at least some role in generating a training effect. Because DOMS is related to muscle damage and muscle damage is believed to initiate the growth process, it should follow that DOMS promotes muscular development. Makes sense, right?
The truth, however, is that DOMS is not a prerequisite for achieving results. Research shows that concentric-only exercise results in significant increases in lean muscle tissue without associated DOMS. Why is this relevant? Well, given the fact that DOMS is induced mainly from eccentric—not concentric—training, the natural conclusion is that soreness doesn’t necessarily equate with progress.
So what is the lowdown on DOMS? When all is said and done, it’s merely an indicator of tissue trauma—nothing more, nothing less. In the initial stages of training, the stimulus of exercise is a shock to your neuromuscular system. Your body doesn’t know how to react to this stimulus, and the chain of events leading to muscular soreness is set into motion.
Unfortunately, there is little that can be done to prevent DOMS (outside of altering your training program). Warming up doesn’t help. Neither does stretching. You can, however, alleviate soreness by engaging in an active recovery. Although the natural tendency is to remain sedentary if you are sore, this is counterproductive. Light activity is generally best, especially concentric-based activities. There also has been some research showing that postworkout massage can be of some help, but this seems to be dependent on the individual.
The good news is that the severity of DOMS will diminish over time. The human body is a very adaptive organism. It readily adjusts to the rigors of intense exercise—even after only a single bout of training. The muscles, connective tissue, and the immune system become increasingly efficient in dealing with fiber-related damage. Various physiologic and structural adaptations take place that gradually reduce any postexercise soreness. Thus, the more that you participate in regular exercise, the greater your resistance to muscle soreness.
The process can be compared to sunbathing. If you stay in the sun too long, your skin will burn. Shortly thereafter, the burn is accompanied by localized tissue swelling that is sensitive to pain. The burn heals over time and the skin becomes more resistant to the rays of the sun. Thereafter, repeated sun exposure results in a tan rather than a burn. While the specific adaptations in tanning are quite different than in training, the basic concept is the same: adaptation breeds resistance.
This is an excerpt from 28-Day Body Shapeover.
