The term D.O.M.S. is used frequently within the world of endurance; it represents the ‘Delayed Onset of Muscle Soreness’. The name refers to the fact that sometimes you don’t actually feel the effects of a training session or race until the following day when you step out of bed.
Those who have run a marathon will understand the sensation. You cross the line and undoubtedly you’re tired but there isn’t a great deal of physical pain. However, the next morning, or perhaps even the morning after that, your attempts to walk downstairs backwards provide the family with the highest level of entertainment they have experienced in their lifetime.
So what’s happened? Has someone been repeatedly battering your tired legs throughout the night whilst you failed to wake from your marathon induced, coma like sleep? The answer lies with D.O.M.S. and the inflammation process.
The inflammation process
During a marathon running event the muscle tissue is damaged due to repeated stress and this triggers the inflammation process. The damage occurs ‘during’ the marathon but the inflammation process takes 24-48 hours to reach its peak, so the pain you feel the following morning was actually happening ‘real time’ during the second half of the race.
An important note to make here is that when people slow down in the final 6 miles of the marathon, we generally assume it is caused by low carbohydrate stores, often termed ‘hitting the wall’.
However, there is likely to be a significant amount of muscle tissue damage by this stage in the race which will undoubtedly have an impact upon performance. Due to the D.O.M.S. effect, we rarely discuss the significance of tissue damage during the event. It’s important to recognise that the pain you experience 24-48 hours after the race is caused by damage which is happening ‘real time’ in the second half of the marathon.
*Part of the inflammatory process involves fluid build up in the damaged area, due to this fluid build up you may weigh more 24-48 hours after the marathon that you did before, perhaps even 1-2kg extra in weight! Don’t worry… it’s just water and it will pass.
How does damage affect performance?
You don’t have to be a rocket scientist to understand that a damaged muscle will not work as effectively as a healthy muscle. However, aside from the actual physical damage directly affecting performance, it’s possible that the inflammation process is acting on a much higher plane and going straight to the governor.
The central governor
There are various theories regarding ‘why we slow down’ and one of the most prominent is the ‘central governor’. This theory suggests that fatigue is controlled by the brain (which can effectively switch off nerve signals to muscles) rather than fatigue being controlled by ‘peripheral factors’ such as the ‘actual muscle damage’.
Okay, here is a simple example:
1. The muscle is damaged and therefore doesn’t work well, as a result you slow down. That is ‘peripheral control’, the muscle is damaged and the muscle doesn’t work, at no point is the brain involve.
2. The muscle is damaged and somehow the brain’s monitoring system detects this. As a result the brain blocks nerve signals to the muscle so it can’t function fully and you are forced to slow down. Alternatively the brain might make you think you’re exercising harder than you actually are to force a reduction in your speed. That’s central governor control as the brain is calling the shots.
*Just because the brain is involved, we are not entering the realms of ‘psychology’.. don’t think that this can be overridden by ‘mind over matter’.. your ‘mental strength’ is not relevant for this discussion although you might need a bit to get through the article..!
Why are we talking about central governor and gone off track from inflammation?
Yep, I was hoping you’d ask that. When we damage a muscle we kick start the ‘inflammatory process’ which is a chain of events involving a chain of chemicals, each having a different purpose and action. One of the most widely researched is a chemical known as Interleukin-6 (IL-6) which is released into the blood stream during early stages of muscle damage and inflammation.
Research suggests that IL-6 is detected by the brain and as a consequence, the brain then acts to slow you down in some way. In one study (completed by Tim Noakes 2004) runners completed 2 separate 10k runs a week apart. They were healthy during both but prior to the second run they were injected with IL-6 and ran almost a minute slower.
Just stop and think about this for one second…
Look at the 2 examples given at the top of this page for ‘peripheral control’ and ‘central control’. These 10k runners did not have muscle damage prior to either 10k, they were healthy, fuelled and ready to go until injected with IL-6, so how can their slower time be explained by muscle damage, low fuel or any other form of peripheral control?
IL-6 has even been suggested as a possible cause for the lethargy associated with ‘chronic fatigue’ or ‘chronic overtraining’. We know that general illnesses and all forms of stress kick start the inflammation process and that in turn would increase levels of IL-6 in the body.
What have we learned so far?
1. I can’t be trusted to stay on track, but you knew that already.
2. The pain you feel 1-2 days after a long distance event is a consequence of damaged which was actually occurring ‘real time’ during the event.
3. Fatigue may be controlled by the brain rather than what’s directly going on at the exercising muscle tissue.
4. The early stages of inflammation generate IL-6 which may play an important role, sending messages to the brain regarding levels of damage.
What can we do to prevent the damage?
1. Damage will be far greater if you’re not conditioned to the distance and terrain. Specifics such as running downhill and running with a pack all need to be considered.
2. It’s possible that damage may be reduced by using compression clothing. Research is very poor but ‘subjective’ feedback suggests that it certainly helps.
3. Nutritional interventions can also help; specific foods and supplements can combat inflammation and help your recovery and performance.
*It’s important to note that the inflammatory process is a vital part of rebuilding damaged tissue, despite the fact that this article views it as a negative occurrence. Don’t take NSAIDs (anti-inflammatories) unless prescribed, they are not the answer.
How do I know if I’ve got tissue damage?
1. It’ll be very ‘tender, warm and swollen’ and if someone squeezes your leg whilst driving you’ll instinctively want to punch them (NB: they never see the funny side of your response).
2. When you stretch, it makes no difference to the tenderness, the pain still exists (it’s not tight, it’s damaged) and it’s probably better if you actually don’t stretch!
What should I do if I have tissue damage?
1. Rest and let your legs recover for a few days.
2. Avoid post event massage or stretching, sticking fingers into or stretching damaged tissue is never a good idea, wait a few days at least.
3. Eat the right foods which encourage reduced inflammation and rapid repair.
4. After a few days do light exercise to encourage blood flow and assist the repair process.