What does it mean?

I recently spoke to someone who had tight leg muscles after doing the Park Run out of the blue: no prior training, warm-up or cool down/stretching. They complained of very tight muscles a couple of days later. I explained that this would be DOMS: delayed onset muscle soreness. If muscles are cold or unused to a certain activity and then worked really hard, they are understandably shocked and complain about it for a while. Wouldn’t you?! The pain generally kicks in about 2 days after the activity but does not last long.

In the short term, stretching may help but massage might work better. Damage may have been done to the muscles and care can be taken to work around this. Stretching isn’t usually very specific.

DOMS usually subsides on its own after a couple of days and so long as the lesson is learnt and no further injury is caused, there may be no long term effects. However, if there was more substantial harm done to the muscle and no action is taken, you may end up with trigger points or weak spots in the muscles. Damage may then accumulate, possibly leading to injury. 

Injuries restrict movement which in turn affects performance and balance throughout the body. Keeping muscles in top working order is extremely important for fitness, and especially if you are competing.

Ideally, training should be introduced, and then increased, gradually so that the body learns to adapt. In this way it is able to grow stronger in a sustainable way, minimising injury along the way.