That pain you feel 12 – 72 hours after a training session. Your muscles get angrier with every movement you make. What is it?
Did I train significantly harder? Did I just come back from a long layoff? Was it the first training session of a new training cycle? Did I add a new movement, train on a new surface (run on trails vs the road), use different equipment (shoes)? For court or field athletes, did I add more changes of direction and/or jumping and landing? Did I train Gi vs no Gi, first real sparring session vs using the bags?
DOMS was first described in 1902. Dr. Theodore Hough stated, “When an untrained muscle makes a series of contractions against a strong spring, a soreness frequently results which cannot be regarded as a phenomenon of pure fatigue.”
“I am unable to state what length of time must elapse to put a muscle out of training; but I have never classified a muscle as trained unless it made an experiment within the preceding three weeks.”
In 2012 an effort was made to define muscle injuries more clearly. This paper defined DOMS as an “overexertion-related” disorder and “generalized muscle pain following unaccustomed, eccentric deceleration movements.” Eccentric refers to the type of muscle contraction. The muscle is lengthening while it is contracting. Think of performing biceps curls and lowering the weight slowly. The biceps is contracting while you lower the weight, but the muscle is getting longer while you do the movement.
“Although DOMS is considered as a mild type of muscle damage, it is one of the most common reasons for compromised sportive performances.” So, what is DOMS exactly? Short answer, we still don’t know the exact mechanisms. Here is what current research says.
- The first symptoms occur in 6 – 12 hours and are due to what is called exercise induced muscle damage or EIMD (yes, lots of acronyms!). For most people the symptoms peak in 24 – 72 hours and then dissipate by day 5 to 7.
- DOMS is related to mechanical damage of skeletal muscle tissue called loss of myofibrillar integrity. Think of each strand in a rope as a myofibril.
- The training you did, the external load, is greater than the force that your muscles can generate by concentrically contracting (the shortening of the muscle like the up phase of the biceps curl). Thus, the theory is that the muscles undergo a lengthening contraction which causes muscle damage.
- Inflammation occurs after the damage to the muscles.
- But, DOMS could also be developed “under submaximal, moderate load conditions, particularly after not familiarized and not well coordinated sporting activities.”