There are several degrees of soreness that we need to be aware of:
- Typical Mild Muscle Soreness: The first type of soreness is the typical mild muscle soreness experienced the day after a good workout. While scientists are still unable to pinpoint the true cause of such soreness, it is generally accepted that it is caused by micro trauma caused at muscle fiber level and by an excess of lactic acid. At either rate, whats important is the fact that this is good soreness as it is of a mild nature and muscle function is not impaired. It generally lasts a day for advanced athletes and up to 3 days for a beginner. This soreness is a good indicator that you had a good workout the day before as you created the trauma necessary to trigger adaptation (e.g. muscle growth). When you are no longer experiencing this type of soreness then that is an indication that your body has successfully adapted to the training program; something that leads to no gains unless the routine is changed once again.
- Delayed Onset Muscle Soreness: The second type of soreness is delayed onset muscle soreness, better known as DOMS. The term DOMS refers to the deep muscular soreness usually experienced two days after the wokout has been done (not the day after). This soreness prevents the full muscular contraction of the muscle. This type of more severe soreness is caused when you either embark an exercise program for the first time or when you train a body part much harder than usual. This pain can last between a couple of days for an advanced well-conditioned athlete or as much as a week for a beginner. If you are being affected by this type of soreness and it is time to workout again, I find that the best idea is not to take the day off, but instead to exercise the body part doing an Active Recovery routine. The Active Recovery Routine that I am referring to here is a routine where all of the loads are reduced by 50% and the sets are not taken to muscular failure. For example, if you are to perform an exercise for ten repetitions, divide the weight that you usually use for that exercise by two and that is the weight that you will use for that day. Also, stop executing the exercise even though you will not have reached muscular failure once you get to repetition number ten. The idea of this type of workout is to restore full movement in the muscle and to remove the lactic acid and other waste from it. Also, to force high concentrations of blood into the damaged area in order to bring the nutrients needed by the muscle for repair and growth. I have always found that doing this is always more beneficial as by the next day you will not be as sore or stiff anymore as opposed to skipping the workout in the name of recovery and waiting for the pain to subside in a week or so.
- Injury-Type Muscle Soreness: The third type of soreness is the one caused by injury. This soreness is entirely different in nature from the ones described above as it is usually immobilizing in nature and very sharp. Depending upon the nature of the injury, it may be experienced only when the muscle is moved in a certain way or constantly. Sometimes these injuries become apparent as soon as they happen. Other times the day after. If you become injured, the first thing that you should do is apply the RICE principle (Recovery, Ice, Compression and Elevation). After consulting a doctor, some injuries may allow you to continue training while working around the injury (in other words, finding the exercises that target the injured muscle without involving the range of motion that triggers the pain). Other more serious injuries, like a muscle tear, may involve complete rest of the injured area, and depending on the severity, it may require even surgery. Therefore, when you weight train, please leave the ego somewhere else. Do not bring it into the weight room as it may cause you to get injured and injuries not only can take you out of the gym for a while, but they always seem to haunt you long after you think that you have fully recovered. So needless to say, the best way to prevent this type of soreness is by cycling your exercise parameters and by constantly practicing good form. (Read more about: Injuries and How to Prevent Them)

