Delayed onset muscle soreness (DOMS)

Delayed-onset muscle soreness (DOMS, muscle fever)) is usually caused by unaccustomed exercise, particularly exercise that requires primarily eccentric muscle action.

• eccentric action occurs when a muscle generates tension to control the rate it lengthens
  
  
• typically the soreness arises within the first day after exercise and peaks in intensity at around 48 hours
  
  
• soreness is usually associated with tenderness and may be associated with swelling
  
  
• series of events that ultimately cause muscle soreness are only partly understood
  • initial event is probably mechanical disruption of sarcomeres (contractile units within muscle fibres). This causes swelling of damaged muscle fibres and initiates an inflammatory response, which could excite nociceptors (receptors capable of transmitting information about pain)
  • muscle soreness is usually only experienced when the muscle contracts or is stretched. This indicates that, while swelling of muscle fibres and inflammation may be necessary for muscle soreness to occur, swelling and inflammation are not sufficient to cause soreness on their own
  • muscle soreness is exacerbated by vibration over the belly of the muscle and pressure thresholds increase when large diameter afferents are blocked (large diameter afferents are nerve cells that conduct information about touch and limb position)
    • indicates that excitation of large diameter muscle afferents, probably primary spindle afferents from stretch receptors in muscles, is involved in generating the sensation of soreness

Prevention

• muscle soreness can be reduced or prevented by gradually increasing the intensity of a new exercise program, thereby taking advantage of the repeated-bout effect
• muscle soreness can theoretically be avoided by limiting exercise to concentric and isometric contractions
• limiting the length of eccentric muscle extensions during exercise may afford some protection against soreness, but this may also not be practical depending on the mode of exercise
• stretching or warming up the muscles does not prevent muscle soreness
• athletes who must train on a daily basis should be encouraged to reduce the intensity and duration of exercise for 1-2 days following intense DOMS-inducing exercise (2):
  • alternatively, exercises targeting less affected body parts should be encouraged in order to allow the most affected muscle groups to recover
  • eccentric exercises or novel activities should be introduced progressively over a period of 1 or 2 weeks at the beginning of, or during, the sporting season in order to reduce the level of physical impairment and/or training disruption.

Treatment

• soreness resolves within about 72 hours after appearing
• any measure that increases blood flow to the muscle, such as low-intensity work, massage, hot baths may help with muscle soreness
• nonsteroidal anti-inflammatory drugs - some studies suggest that NSAIDs attenuate muscle injury and perceived soreness while hastening strength recovery
• continued exercise may temporarily suppress the soreness. Exercise increases pain thresholds and pain tolerance. This effect, called exercise-induced analgesia, is known to occur in endurance training (running, cycling, swimming), but little is known about whether it also occurs in resistance training
• cryotherapy, stretching, homeopathy, ultrasound and electrical current modalities have demonstrated no effect on the alleviation of muscle soreness or other DOMS symptoms (2)

Notes:

• Repeated-bout effect
  • after performing an unaccustomed eccentric exercise and exhibiting severe soreness, the muscle rapidly adapts to reduce further damage from the same exercise

Reference:

• 1) Herbert RD, de Noronha M, Kamper SJ.Stretching to prevent or reduce muscle soreness after exercise.Cochrane Database Syst Rev. 2011 Jul 6;(7):CD004577.
• 2) Cheung K, Hume P, Maxwell L.Delayed onset muscle soreness : treatment strategies and performance factors. Sports Med. 2003;33(2):145-64.