Babies love to be held, and of course they NEED this snuggle time, however learning to entertain themselves, I think it's an important part of development!! You may have to deal with crying for a while until he understands you can't hold him all the time, the older they get the harder this habit can be to break. When my kids went through a clingy phase, I used words, not baby talk, and explained that it's time to play or mommy has to do some work. I would put my kids in a safe place, (but never their bed, because I saved the crib for sleeping only) so a play area that is inclosed worked for me, or walker. You will have an angry baby, the first few times but they learn fast if you are consistent. Try to keep things on a schedule and it will help him understand what to expect. To this day all of my kids respect my workout and pole time. When my youngest was little I would have him in the room with me (but in a play seat so he was safe) while I poled or worked out, so I could keep an eye on him. Kids need to see mommy's taking time for themselves too. :)