Quadriceps soreness from running and walking

During last year or so I noticed that my quads get sore not only from running but  walking too. I do not understand where it comes from since before that I had been able to walk for quite long distances although I have flat feet but walking shod in running shoes always helped. Now I can walk for 10k but for next couple of days my quards are sore. Stronest pain is in the low parts of muscles where they are attached to knee bones.

I'm a cyclist but also a runner wanna-be but I quit running and switched back to cycling in December because of this soreness. I had to stop running and minimize about of walking and it took two weeks to recover.

What cause can it be?  Any ideas?

DOMS is unaccustomed activity usually the eccentric part of the muscle contraction (when it's stretching under gravity). So if you walked 10K regularly, would you still get the muscle soreness? If yes, then there's something more than muscle soreness going on.

The best cure to prevent muscle soreness it is to do an activity to overload the muscles eccentrically, bizarre as it sounds. This is because once 'damaged' there's a protective effect if you do a similar activity.

E.g. week 1's game of squash leaves you very sore 12-48 hrs afterwards, but the next week you're not as sore. Adaptation, protective effect and conditioning all play a part.

Try some squats or lunges to condition your quads. And the worst thing you can do after a strenuous bout of eccentric muscle loading is to have a hot bath - makes the inflammation far worse!

I'm used to heavy muscle stress, I'm a racing MTB-er and I race long distance, that is marathons and enduro, I'm used to hours of stress and cramps.

what worries me is that the load to cause soreness is not even moderate but less than moderate. Regular active long distance walking and running make my case worse and worse like the muscles never rest and are contantly overloaded which forced me to quit running although I was coping with other running stress factors quite well.

I experienced something similar, remember clearly rubbing my quads and complaining to my physio that they ached but that i felt it wasn't DOMS. Turns out i have a lumbar disk issue and it was referred pain, well ache.

thanks fikalina, that's a bit frightening...  I guess I have to check my spine.

Siance: dropping running and getting back in the saddle helped to recover but if I go for a walk then I'll the this issue with sore quads again though slight but tangible.

Could try having your biomechanics checked by a pod. I've always had doms even after short runs. I'm now on my third set of orthotics  I no longer get it thank goodness .  I never stretched before my run but now  gently stretch my hams and calves after a 5 min walking warm up before setting off. Always stretch after.  Plus I've started doing quad and ham weights in the gym to strenghten my legs.

 Good luck.

D