Everyone has experienced muscle soreness at some stage regardless of their fitness level. Occurring after unfamiliar or eccentric exercise, the muscle fibres experience some damage at a microscopic level. This leads to loss of strength, decreased ROM (range of motion) and a temporary decrease in neuromuscular function. This is referred to as DOMS (Delayed Onset Muscle Soreness) and starts after 8-12 hrs, peaks at 24-72 hrs and dissipates 5-7 days after exercise.
There is no doubt that eccentric exercise plays a large, but not exclusive role in producing DOMS. Eccentric actions occur when the tension in the muscle is less than the resistive force (load). The muscle lengthens as tension is generated while fewer muscle fibres are recruited creating more force being applied to those fibres. This would make those fibres more susceptible to structural damage.
To date no research has been able to attribute any one mechanism to the sensation of DOMS or to muscle fibre damage. Rather a sequence of events have been suggested to produce the symptoms of DOMS. They are: damage to muscle ultrastructure > accumulation of calcium > release of intracellular proteins > inflammation that activates pain receptors.
One fact that is indisputable is that the magnitude of DOMS is directly related to the intensity (%RM) and duration of the exercise.
Many methods have been studied to reduce DOMS. Anti-inflammatory drugs, anti-oxidant supplementation (vitamins C & E), cold packs, post-exercise stretching, topical anti-inflammatory creams, have all provided conflicting results. The most promising method so far has been the use of an efficient warm-up. Increased muscle temperature leads to a reduction in muscle and connective tissue viscosity, a higher resistance to muscle tearing and increased muscle elasticity.
To minimise DOMS follow the recommendations listed:
Perform a general warm-up (5-10 mins)
Perform a specific warm-up
When beginning a new exercise regime avoid excessive eccentric movements (heavy negatives, plyometrics, down hill running)
Gradually increase intensity and duration of sessions over time.Behm, D.G. et al (2001) The effect of muscle damage on strength and fatigue defecits. J of Strength and Cond Research. 15(2), 255-263.
Szymanski, D.J. (2001) Recommendations for the avoidance of delayed-onset muscle soreness. Nat Strength and Cond J. 23(4), 7-13.