Re: Do swimmers recover quicker than runners?

Hello Bryan,

Thank you for your interesting question.  Having given it some thought I 
think that I have come up with an explanation for what you have observed.

I do not think that swimmers recover any quicker than runners following 
competing in an event.  I would be more inclined to think that swimmers 
take longer to recover, since swimming uses both the legs and arms and 
therefore more muscles.  During a competitive event the athlete will be 
working their muscles at a level that will be above the level of normal 
aerobic respiration.  At this point they start to generate a chemical 
called lactate in their muscles, which can then be converted to lactic 
acid. For more information on lactic acid generation in muscles look 
at this previous answer to a question.


For muscle to work under normal 'aerobic' conditions they need a supply 
of oxygen. However when all the oxygen that the body is capable of 
supplying to the muscles is used up the muscles can still perform at an 
elevated level for a short period of time.  This results in the generation of 
lactate as a bi product, which needs oxygen to be broken down at a later 
stage and this is termed an 'oxygen debt'.  The muscles have been 
designed to work in this manner for short periods of time but they then 
need time to recover.  So when an athlete is breathless at the end of an 
event it is due to this oxygen debt being repaid.  

The predominant muscles used in running are obviously the legs with 
some small effort from pumping the arms through the air.  However 
swimming makes use of both leg muscles and arm, chest and back 
muscles (which muscles exactly depends on the stroke being 
performed).  Therefore the swimmer will be using more muscle mass 
during their event than the runner.  I would therefore assume that the 
swimmer is capable of generating more lactate in all these muscles that 
the runner is in their leg muscles.  Therefore the swimmer will have a 
greater oxygen debt to pay and will therefore take longer to recover.

However I do agree with you that runners look more tired after an event 
than the swimmers but I think that this is for a different reason.  
Basically the swimmer is well supported by the water that they are in at 
teh end of the event and therefore require less energy to do nothing, 
whereas the runner requires energy to remain standing.  So the swimmer 
can float in the water, expending very little energy on maintaining their 
posture so more of the oxygen that they take in goes towards paying off 
their oxygen debt.  Also if the swimmer were to relax to the same extent as 
the runner lying down they may sink, which would obviously not be very 
good for them.  So the runner lying down is expending less energy on 
maintaining posture to get more oxygen to the muscles that are in short 
supply.  So i guess the final answer to your question is that a swimmer 
does not recover more quickly than a runner lying down but the swimmer 
is in a better environment than the standing runner for recovery since they 
have to use less energy to maintain posture.

In addition when the athlete has finnished their event they will go off and 
warm down, which will involve doing more slow exercises to remove the 
lactate from the muscles.  Some of the lactate generated in the muscles 
can be converted into lactic acid, which is responsible for muscles feeling 
sore after vigorous exercise.  Working the muscles at a low level will keep 
lots of blood flowing through and remove this bi product from the muscle.  
So the athlete doesn't fully recover from their event until long after they 
have dissapeard off the television screen and probably gone away from 
the venue.

I hope that this all makes some sense and answers your question for 
you.

Dave Burton