Will intense workout help prevent injuries?

>> on the quest to stay healthy, millions of americans are treated for sport's related injuries every year. one doctor is trying to prevent them before they happen with a total body work out. he's completed 29 marathons and nine iron man triathlons. i had to check it out for myself. whether you're an athlete in your 20s or 70s, exercise can take a toll on your joints.

>> i have run 23 marathons.

>> i certainly have gotten injured from running.

>> hopefully once i'm past my knee injury i will be a more intense athlete.

>> 30 seconds.

>> reporter: according to dr. jordan metzel it's the lack of body strength that leads to injury.

>> everybody here is a runner, tri athlete and wants to prevent injury. rather than spend time in doctor's offices i want them to prevent injuries.

>> reporter: which is why he created the iron strength work out which he teaches twice a month in new york.

>> it's strength and cardio. you can do it a couple times a week. this helps anybody at any level.

>> reporter: i have had a couple of injuries.

>> all the injuries are related to not having the muscular support around your skeleton. i will teach you how to reduce the loading force on your bones. the stronger the muscles, the less likely you are to get injured.

>> reporter: with dumbbells and determination i was ready. i'm already going for the water. this will be a long class.

>> i have no balance.

>> just like running.

>> reporter: harder. halfway through the class i was feeling the burn.

>> i won't be able to sit down tomorrow.

>> reporter: at the end it was a combination of squats, push ups and jumps which is the burpee.

>> they kick my butt.

>> i hate them.

>> reporter: the person who did the most took home the burpee cup.

>> i'm not winning it. i'm trying to survive.

>> reporter: the workout is about more than winning a trophy.

>> i was nursing injuries, running through pain.

>> not going to get injured again. hopefully with this kind of strength training which is good for my body.

>> i just want to be as strong as i can. i want to be the hottest body an old broad can have.

>> reporter: that looks darn good as well. the winner was 33-year-old joey egan the first to do 55 burpees. i hate them. dr. metzel, good morning.

>> good morning.

>> you put me through it. it was a great workout and it taught me a lot. one of the most common mistakes people make when they get out there.

>> the key mistake as far as i see it as a sports medicine doctor is people don't goal set. i know people watching on tv thi think, i'm home with three kids. i don't have time for a work out. but give yourself a goal. ballroom dancing , the track, lack of goal setting is the most common thing i see in my practice.

>> and be realistic with goals, too. there are fitness misconceptions out there. first, coffee is a good idea before a work out. true or false?

>> rejoice. it's true. the science on coffee is convincing. maybe two cups can increase skeletal muscle contractility. you get more.

>> with the milk?

>> sure.

>> stretching before exercise is worth the effort. we hear it a lot. true or false?

>> if you're a stretcher before exercise, it's probably not as good as you think. we start with a dynamic warm-up. instead of bending over and touching your toes, easy jumping jacks or jogging in place can warm up your muscles and get you ready for exercise in a safer way.

>> warm-up is key. bad injury lands you in a doctor's office and people always think you end up with a torn -- if you have a torn ligament that shows on mri that you are going to need surgery. is that true?

>> as technology changed we have seen a shift. mri has changed the face of sports medicine . we see all kinds of things. i brought an mri to show you. mri shows me the inside of somebody's knee.

>> when you see this you can get around this working out?

>> the red arrow points to the tear in the meniscus. the important thing to impress upon patients all the time is just because something shows up on mri doesn't mean it needs surgery. patients need to educate themselves as to what needs surgery and what doesn't.

>> there is a lot more on the website about your workout as well. doctor, thanks. coming up, we'll tell you how to cut the financial