The pain you feel 24-48 hours after a workout is usually due to delayed onset muscle soreness (DOMS). Your muscles will get sore any time you start a new exercise program, change a workout routine, increase the duration or intensity of regular workout sessions, or perform any type of physical activity to which the body is not used to.
When you lift weights, you create microscopic damage to the muscle in the form of small tears. As a result, the body creates a short-term inflammatory response to kick-start the rebuilding process. This is what leads to the adaptation of the muscle, as it requires the body to build more muscle fibers and improve blood supply so that the next time we train there is less ‘damage’.
The answer to this question depends on the severity of muscle soreness, which can range from slight tenderness to debilitating pain. During periods of severe muscle soreness, a person has impaired coordination, less shock absorption, and a shortened range of motion. If you exercise while very sore, you are likely to alter your body mechanics putting more stress on ligaments and tendons and therefore increasing your risk of injury.
If you’re only slightly sore, exercise can bring relief, although only temporarily. Take it easy by doing light resistance exercise or by doing low-intensity cardio (such as walking). If you do cardio, do it immediately post weight training (not 1-2 days later) if you want to reduce the recovery time from being sore.
Large muscle groups such as the quadriceps and hamstrings should be given a greater amount of time to recover (72 hours) while smaller muscles, especially the postural muscles of the core, are built for endurance and therefore can be exercised more frequently, such as every 48 hours. People who lift weights every day will split their routines so they can work for different muscle groups on different days.
Muscles don’t grow during a workout, only during rest periods following exercise. If you don’t allow your body to recover, you won’t see the benefits of your workouts. You absolutely must rest the muscles you worked for 1-2 days after a workout. Take at least one day off between strength training sessions, and if you are still very sore, take 2 days off. (This means from lifting, not from all exercise such as cardio). If you don't let your muscles recover and repair, they will continue to break down and you will actually get weaker.
To help prevent soreness in the future, and alleviate some of it now try:
1. Warming up for 5-10 minutes and cool down for at least 5 minutes.
2. Stretching after a warm-up, during your workout, and after you are done.
3. Staying active. The more your muscles move, the faster they will recover from exercise and soreness.
4. Foam rolling at the end of a workout. It creates blood flow, which has been shown to decrease muscle soreness
5. Massaging the affected muscles.
*Cold baths and pain relievers can also help in some extreme cases of soreness.
Training through mild soreness is unlikely to be a problem, and the workout itself will even help to relieve the DOMS, at least for a short while.
Extreme soreness, on the other hand, is a sign that you’ve gone too far and that your muscles are struggling to recover and repair. If you’re really feeling the pain, listen to your body and take a break from your workouts.