This happens every time. Is it ok? I guess not. My knees so painful when bend.

I dindt overdo it i think. I built up slowly.

Im 46 do I just have weak knees and best to avoid leg exercises?

maybe you do the wrong exercise, or do it wrong.

What do you do exactly?

More history needed.

How long have you been using the machine "building up"?

Which machine is it?

Have you had any history of knee problems?

What type of pain is it? If you have suffered a serious injury then attempting to walk and stretch it out could be counter-productive and aggravate the injury. On the other hand, if its just the typical pain found after starting a new weight training routine then the best thing you could do would be to walk and get the muscles flowing with fresh blood.

Probably first off you need to take some anti-inflammatory and apply occasional ice to the area for the day. Maybe 10 minutes every 40 minutes.

Perhaps focus on non-weight bearing exercises such as cycling first and see how that goes before weight bearing.

This may be a very early indication of osteoarthrosis where the lubrication in the joint is reduced leading to pain after weight bearing exercise. Cycling helps to "lubricate" the joint better than weight bearing.

Yes this can happen if you just start training. Its quite normal for people to overdo it at first and suffer the consequences for a week. I know I have that problem if I start again after a few weeks off. I even know that its going to happen and exercise a bit lighter. But after training for a while the muscle aches get less.

Though I have never a problem bending my knees more just severe muscle pains.

Perhaps focus on non-weight bearing exercises such as cycling first and see how that goes before weight bearing.

This may be a very early indication of osteoarthrosis where the lubrication in the joint is reduced leading to pain after weight bearing exercise. Cycling helps to "lubricate" the joint better than weight bearing.

Warming up always helps and should be done before weight exercise. Certainly now more then when i was 20. By doing so you avoid a lot of injuries.

You over trained for sure. Start with lunges. If you do them properly you won't need weights. As you get stronger do them carrying dumbells.

Or you can do Yoga and everything about your life will be perfect.

Perhaps focus on non-weight bearing exercises such as cycling first and see how that goes before weight bearing.

This may be a very early indication of osteoarthrosis where the lubrication in the joint is reduced leading to pain after weight bearing exercise. Cycling helps to "lubricate" the joint better than weight bearing.

could be also a problem with tendons and/or not doing it right (having a torque on the joint which the knee can't handle well).

We need more informations....

Or you can do Yoga and everything about your life will be perfect.

Yeah, and your boyfriend will love your body.

I used to crush myself with legs. Got sore the next day, but had that "No pain, no gain" mentality. Got ripped but couldn't put on mass. Then I read "The 4-Hour Body" by Tim Ferris.

Now when I train legs I do 1 set with moderate weight slowly with a 5 second down count and a 5 second up count. I go until i fail. (Make sure you are doing a safe exercise or have a spotter if you are going to failure)

The theory is that, this is all your muscles need to stimulate growth. If you do too much you are actually hurting yourself.