I wonder if it is really true that you can work muscles like calves and forearms everyday or at least fairly regularly simply because they were already made to adapt to constant strain due to us having to grab or walk all the time?
Well, ask yourself this - are monkeys strong? How about bull elk? Bears? Yet none of them ever take a day off, nor do they look around for dead weights to build up their muscles.
I do believe that you can easily work any muscle group every day. You just can't do it with heavy dead weights. You can walk a mile uphill every day, and your thighs, calves, even your shoulders will get stronger.
I know of several stories of weight-lifters who got tired of the torn muscles, damaged joints, and general weariness that they felt, who started doing body-weight exercises and found that they weren't as strong as they thought they were. They started doing squats, pushups, bear crawls, handstand pushups, and back bridges every day, and after a few months decided to just try a dead weight workout again, and found that they were stronger than they had been when they were only lifting dead weights. And they no longer experienced the agonies.
So, depending on the exercises you use, yes, you can exercise specific muscle sets every day, without harm.
Maybe I should have clarified my original question with more reference material / facts. My main interest for asking this is based on muscle development as far as both growth and strength. Unlike other muscle groups the calves and forearm muscles are supposed to be more resilient to concentrated exercises thus enabling them to take quite a lot of punishment before needing to rest totally and recovery taking place. Now, we must also remember that there is the difference between red and white muscle tissue (fast and slow twitch) which can affect the speed , duration and amount we lift at for one rep, but my interest is not on how strong or how fast as you have indicated, but on recovery. For a muscle to grow it must be recovered from its last workout - so in other words I am asking - Do the calf and forearm muscles recover more rapidly so as to allow daily workouts towards muscle growth? From personal experience I find that it can take harsh treatment 3-4 days a week (at least for me) and still grown without being over trained.