How are you training? many weight training exercises (especially low rep high weight) and short cardio exercises won't give you better endurance, they'll get you faster and stronger.
I started crossfit a couple of months ago. It's a wide variety of weight, cardio and other exercises. One time the warming up started with a 3 km run, and that's just pointless to even try for me. I'm better with the exercise bikes, but anything that involves running or jumping will wreck me before I get anywhere.
I have been running for a long time, but it had always about 3 mile lengths, and never super long distances until 2 years ago. >6 miles was almost impossible. the key for me to run longer was to run my limit, hit the wall and keep going, and after a run a week for months, then I'm doing 8 mile runs, 10 mile runs, 20 mile runs. eventually, I hit a second wall: boredom. I don't think that super high endurance is very rewarding, at least not for me, and to get better at it requires a lot of pain, and even potential for injury (and then you can't train and you go back a few months). I also think the health rewards of runs reach an inflection point around 5km, especially after factoring risk of injury.
if you can't do a 3km run, run 1, or 2. then wait ~48-72 hours, and run 2 again. eventually, you'll be able to run 3, I guarantee it. but what is a lot less certain is whether you'll enjoy it and feel rewarded. I've found the more endurance based an activity, the more mental it becomes, just as original comment was getting at. for some people, thats good because its the only way they can be competitive. for others who have more athletic talent, it may be frustrating because it takes more effort than most other exercise.
I hit that wall right away. There are few exercises I find more boring than running. I did run with a couple of friends for a short period, because I felt I didn't see them nearly enough, and this was a nice way to see them more often and get some exercise at the same time. I hope that meeting my friends would make me more motivated. We still couldn't keep it up.
The only time when I can really run is when I think an emergency might be threatening my youngest kid. I think I could beat Usain Bolt in that situation. It's definitely mental.
I've been bad with endurance my whole life until I did the Couch-to-5k training program. Doing a 1-mile run in school was always a nightmare for me. It's a fantastic 8 week training program that alternates between run days and rest days. It starts off with run 1min, walk 2min, run 1min, walk 2min until 30min. Then it progressively gets to longer running components. I was blown away by the human body's ability adapt to stresses of running. The first week I was dying just from running 1min, walk 2min. Then mid way through, running 10min, walking 1min became a piece of cake. I heartily recommend it if you're trying to get into cardio.
Sounds good. I think my wife may have done something like that a couple of years ago. Sadly, she quit. But before she quit, she definitely noticed significant progress.
