In my own experience, as I have not found a way to transfer other people's physical pain unto myself, there are two types of pain: the pain from working your muscles, and the pain from doing something wrong.

The first thing that you should learn when doing a new exercise is what the difference between these two pains are. Then, when performing more rigorous forms of the same exercise, you can establish where you can push through the pain. Is the pain you are feeling exhaustive? Push through. Is the pain something foreign? STOP IMMEDIATELY.

This, I think, is one of the reasons why it is suggested to do a lighter exercise before engaging in the intense stuff. As well, you don't run the risk of learning the difference between the two pains too late into the exercise. In general it follows along with the trite quotes: "You have to learn to walk before you can run," and "Start slow to go fast."

I always take the advice of "push through the pain" as pushing through the pain of exhaustion, which will contribute to strength and your ability to push beyond current physical limits; whereas the advice of "listen to your body and stop when it hurts" is more related to injuries - if you have a constant muscle cramp, or joint pain, or a stress fracture, or a ligament issues... REST and recuperate. Pushing through this second sort of pain will very likely result in injuries worsening and requiring even longer to mend down the road.

As I understand it, there's breaking a sweat and being uncomfortable, and then there's pain. If you feel pain it's time to stop for the day or at least take a good rest.

Depends on the pain. If you're running and your muscles get sore, by all means keep going within sane limits.

If you get a stitch in your side there's no harm in pushing through, they're painful but not harmful.

If you get shin splints or your knees hurt, stop and figure out what's wrong before you damage something.

As always, it depends..

Depends on the end goal. If you can only complete two miles and you're signed up for a marathon a month from now, you're going to have to push past your comfort zones.

But if your end goal is to be able to go up a flight of stairs without heavy breathing, to sustain vitality through your older years, then no, do not push. Do just the amount of effort that will allow you to keep coming back, day after day.

Many beginners would be surprised how slow or lightly they should be going if they monitored and targeted heart rate. There is discomfort and pain. If you're feeling massive exhaustion and/or pain, you may be doing something wrong.

I think one big issue is that people who are new to an exercise (or exercise at all) don't have a sense of scale, and don't realize quite how much progress they'll make early on.

If you know some people can run marathons, it doesn't sound crazy to think "well, I ought to be able to run for 10 minutes without any problems", but there are a lot of people who would risk seriously injuring themselves with 10 minutes of quick-pace running. Not to the point of rhabdo, probably, but certainly not a healthy experience.

It also doesn't sound crazy to think "Well, I'm in agony after two minutes, but there's no way that means I should stop. I'll never get anywhere with only two minutes of running!" But of course, 'beginner gains' are distinctive - someone who hasn't done cardio in years might be at two minutes today and six minutes next week.

The only universal answer I know to solve this is to take your first few outings in a new thing lightly. Don't even set a training plan, just go out until you're a bit uncomfortable, then stop and see how you feel the next day.

This is very difficult. One thing when you should consider stopping is if the pain becomes chronic and never goes away. I remember seeing a lot of top fighters pretty much living on pain killers. That's probably a clear sign you should stop.

I got a lot of benefit from doing intense martial arts when I was younger but sometimes I wish I had been smarter and not just ignored pain. But again, it's a difficult decision. Some things make you tougher and some things cause problems later on.

Pushing through the pain barrier is wrong, point of training is to find that subtle balance where you push enough to advance but not too much to avoid injury.