Why does my knee hurt when i bend it?

Not to be unhelpful, but have you considered talking to your doctor?

You should definitely get this checked out with a doctor. They’ll send you in the right direction.

IT band? More stretches with those work outs!!

You have over done it. You have poured on a lot of new high intensity exercises your muscles were not used to and sounds like the muscles were not used to all this new stress. Get a good knee brace to help support your knee from “rolling” to the outside.

http://familydoctor.org/online/famdocen/home/healthy/physical/sports/147.html

As one who has had arthroscopic surgery on his knee, I would suggest resting it immediately and stop any activity to the legs for a couple weeks, Just work on upper body. You’ll thank yourself later.

Since your recent addition has been accompanied by your recent condition,
yeah there seems to be a connection.
Your diagnosis could be in the ball park,
You probably should have it looked at right away if you can.
suggest you stop the elliptical for a week and ease off on everything else for a week as well. your pain should go away, if your pain increases, please have someone take a look at it ok?

Do you happen by any chance to have a small bony lump on that knee, like it is more of a lump compared to your other knee?
if so you might have Osgood-Schlatter disease

dont get freaked out. I have it too. It is just what came to mind when you said knee pain and also you are sporty (common in sportspeople)

I’ve always worked out hard but it’s taken me to 42 to really think holistically. Maybe I can save you some serious strain and offer you the benefit of some hard earned and painful experience.

Cardio and weightlifting alone will not reduce the strain on your joints. You must lose weight. Diet and nutrition is way more important than people imagine in the equation. In fact eating consistently and the right foods is instrumental to fat loss.
In one study 4000 people were tracked over 4 years. Among those who ate a 250 calorie breakfast and those who ate a 450 calorie breakfast, the latter actually lost twice the weight of the former!
University of Massachusetts researchers recently discovered that men who don’t eat in the a.m. are 4.5 times more likely to be obese than those who make it an everyday habit. In fact, during the year-long study, the men who reported missing breakfast just one time increased their obesity risk by 34 percent.
www.menshealth.com
Consider the following example also: In order to burn one pound of belly fat through crunches alone one would have to perform 250,000 crunches. At 100 a day that’s 36500 in a year and would take you nearly 7 years!
Or you could reduce your caloric intake and start seriously adressing the process with a sytemized approach to overall health and fitness. I’ve lost 20 pounds in the last month on this program including eating plan and really kicked up my metabolism big time. Check it out. The fully loaded program has excellent compound strength cardio and interval training programs that will burn fat-serious core workouts, iso holds etc.

P.S.- My diet today: 3 eggs, glass O.J., Yogurt, banana, 2 PBJ sandwiches on whole grain bread, apple, almonds, banana, steak, green beans, baked potato, one beer (non alcoholic), and a square of dark chocolate. Hardly deprivation huh?

Not knowing details and going on my own experience (had a torn meniscus once and tendonitis many times), I’d speculate that the main cause may be the high-impact sprints you’ve incorporated into your workout. Running is death on your joints from the knees down, especially if the body isn’t used to it. When your foot hits the pavement, those joints are actually taking on many times your body weight with the impact. The elliptical is great because it’s much easier on those joints. See what a doctor has to say about all this.

Great start on a workout schedule, btw! Damn, that’s ambitious. Remember to take care of yourself… soon enough you’ll be at an age where shit like angry knees catches up with you.