Japanese Muscle

Is it the same day, the day after or second day after playing sport or doing excessive exercise when your body starts to give you pain? Why can it take so long for this aching feeling to affect us?

I'd always thought that fit people normally felt muscle aching the second day after pushing their bodies. I'm not sure where I got this information from or whether it's just some kind of myth.

On a number of occasions the Japanese people I play tennis with have said that as you get older the pain or muscle ache takes longer to set in. So which is the correct answer? Does each culture have a different idea about this or am I just wrong?

The Japanese have a word for this kind of muscle pain, 筋肉痛 ('kinniku-tsu'), literally, muscle pain. It feels so much easier to say than something like 'my muscles ache from...' though now that I type it out it doesn't seem quite so long winded.

I guess if you were very very fit you wouldn't get this kind of pain at all, though even the best athletes have to watch out for repetitive strain injuries.